APPENDIX -IV

REPORT ON

HYDROGEN PRODUCTION IN INDIA

Prepared by the

Sub-Committee on Research, Development & Demonstration

for Hydrogen Energy and Fuel Cells of the

Steering Committee on Hydrogen Energy and Fuel Cells

Ministry of New and Renewable Energy,

Government of India, New Delhi

June, 2016

FOREWORD

Till the end of 20th Century carbonaceous substances like coal, natural

gas, petroleum derived oils and wood were fulfilling the of energy needs of

human society for heat, light and power (both motive and electric). With the

passage of time, the rising world population and urge for better living

standards by the people of developing regions of the world have resulted in

over exploitation of conventional energy resources. This in turn has led to the

increase in the demand for energy and reduction in availability of conventional

fuels. Emission of various types of pollutants (such as particulates, carbon

dioxide, and un-burnt hydrocarbons) as a result of the use of these fuels is not

only affecting the health of living beings adversely but also contributing to

greenhouse effect and climate changes. In view these concerns and ensuring

energy security, the focus in the futuristic energy planning is shifting from

carbon rich to carbon neutral and carbon free new and renewable energy

sources. Hydrogen has been considered and identified as the potential energy

carrier and as a leading contender for the “ideal” energy option of the future.

On combustion it emits only water vapor. It may be produced through natural

gas reforming, coal and biomass gasification, thermo-chemical route using the

heat available at high temperature from nuclear reactors, electrolysis of water

with surplus electricity available from grid or that produced from renewable

sources of energy like hydro, wind, solar etc. Biological (fermentative and bio-

photolysis), photo-catalytic splitting of water (or photolysis), and photo-

electrochemical methods are being considered as futuristic routes of

producing hydrogen. Sufficient amount of hydrogen is also produced as by-

product in Chlor-Alkali units and petroleum refineries

In view of the rising aspiration of the increasing population, India is also

concerned about the climate change and is therefore striving for developing

technologies for harnessing renewable energy sources. Hence, hydrogen

energy and fuel cell technologies are of utmost importance, which India needs

to develop in a mission mode. Though the Ministry of New and Renewable

Energy (MNRE) and several other government agencies at the central and

state government levels are providing support for research, development and

demonstration of hydrogen production and application, yet India is lagging

behind while considering the global scenario. The MNRE, Government of

India constituted a high power Steering Committee to prepare a status report

and suggest the way forward for development of hydrogen energy and fuel

cell technologies in the country. One of the five sub-committees was entrusted

under the chairmanship of the undersigned with the responsibility of preparing

this particular document focusing on the research and development of various

hydrogen production technologies of relevance to the country.

This document is the result of the combined effort of all the members of

the sub-committee, experts working in the area of hydrogen production,

officials and staff of MNRE.

I am indebted to all the Members of the Sub-Committee and Special

Invitees for their contribution, Dr. M. R. Nouni, Scientist ‘G’, Ministry of New

and Renewable Energy and also the officials of the Project Management Unit

– Hydrogen Energy and Fuel Cells at the Ministry, Dr. Jugal Kishor and Dr. S.

K. Sharma in particular for their active role in organizing meetings and

preparing this document.

30th June, 2016

(Prof. S. N. Upadhyay),

Chairman,

Sub-Committee on Research, Development &

Demonstration for Hydrogen Energy and Fuel Cells

CONTENTS

Sl. No.

Subject Page No.

I

Composition of the Sub-Committee on Research,

Development & Demonstration for Hydrogen Energy and

Fuel Cells

i

II Terms of Reference ii

III Details of Meetings iii

1 Executive Summary 1

2 Introduction 25

3 Hydrogen Production using Thermo-chemical Route from

Carbonaceous feed-stocks:

(i) Carbonaceous feed-stock

(ii) Biomass feed-stock

35

37

54

4 Hydrogen Production by Electrolysis of Water 69

5 Bio-Hydrogen and Bio-Methane Production 95

6 Hydrogen Production through Thermochemical Routes

(Iodine-Sulphur and Copper-Chlorine Cycles)

105

7 Hydrogen Production by Photo-electrochemical Water

Splitting

149

8 Hydrogen Production by Other Technologies 163

9 Action Plan 171

10 Financial Projections and Time Schedule of Project

Activities

181

11 Conclusions and Recommendations 189

12 Bibliography 199

13 Annexure 207

i

I Composition of Sub-Committee on Research,

Development & Demonstration for Hydrogen Energy and

Fuel Cells

1. Prof. S. N. Upadhyay, Former Director, Institute of Technology, Banaras

Hindu University, Varanasi and DAE-Raja Ramanna Fellow in the

Department of Chemical Engineering and Technology, Indian Institute of

Technology (Banaras Hindu University), Varanasi - Chairman

2. Ms. Varsha Joshi, Joint Secretary / Shri A. K. Dhussa, Adviser

(December, 2013 to March, 2015) / Dr. Bibek Bandyopadhyay, Adviser

(upto December, 2013), MNRE

3. Dr. Sanjay Bajpai, Scientist ‘G’, Department of Science and Technology,

Ministry of Science and Technology, New Delhi

4. Dr. Ashish Lele, CSIR-National Chemical Laboratory, Pune

5. Dr. S. Aravamuthan, Sci./ Engr.- ‘H’ & Deputy Director, Vikram Sarabhai

Space Centre, Indian Space Research Organisation, Thiruvanthapuram

6. Shri A. Srinivas Rao, SO/G, Chemical Technology Division, Bhabha

Atomic Research Centre, Mumbai

7. Dr. K. S. Dhathathreyan, Head, Centre for Fuel Cell Technology, Chennai

(Retired on 31.01.2016)

8. Prof. O.N. Srivastava, Emeritus Professor, Banaras Hindu University,

Varanasi

9. Prof. B. Viswanathan, Emeritus Professor, Indian Institute of Technology

Madras, Chennai

10. Prof. Debabrata Das, Indian Institute of Technology Kharagpur,

Kharagpur

11. Prof. L. M. Das, currently Emeritus Professor, Indian Institute of

Technology Delhi, New Delhi (Retired on 30.06.2014)

12. Executive Director, Centre for High Technology, Noida

13. Dr. P. K. Tiwari, Desalination Division, Bhabha Atomic Research Centre

as Representative of Principal Scientific Adviser to Govt. of India,

currently Raja Ramanna Fellow at the Prof. Homi Bhabha National

Institute, BARC, Mumbai (Retired on 31.01.2015)

14. Shri Sanjay Bandyopadhyay, National Automotive Testing and R&D

Infrastructure Project (NATRIP), New Delhi / Shri Neeraj Kumar, Deputy

Secretary, Ministry of Heavy Industries & Public Enterprises, (Repatriated

to Parent Department in January, 2015) / Shri Nitin R. Gokarn, NATRIP,

New Delhi (Repatriated in June, 2014 to Parent Cadre)

Special Invitees:

15. Prof. S. Dasappa, Indian Institute of Science, Bangalore

16. Dr (Mrs.) V. Durga Kumari, Indian Institute of Chemical Technology,

Hyderabad

ii

II Terms of Reference

1. To review national and international status of Research & Development,

Technology Development and Demonstration with a view to identify the

gaps.

2. To suggest the strategy to bridge the identified gaps and the time frame for

the same.

3. To assess R & D infrastructure in the country.

4. To identify projects and prioritize them for support with the result oriented

targets.

5. To identify institutes to be supported for augmenting R&D facilities

including setting-up of Centre(s) of Excellence and suggest specific

support to be provided.

6. To suggest strategy for undertaking collaborative R & D among leading

Indian academic institutions and research organisations and also with

international organisations.

7. To examine setting-up of a National Hydrogen Energy and Fuel Cell

Centre as an apex facility.

8. To suggest strategy to take-up projects in Public-Private Partnership mode

for the development of technologies based on transparency, accountability

and commitment for deliverables.

9. To identify the technologies, which can be adopted for applications with

time line?

10. To re-visit National Hydrogen Energy Road Map with reference to

Research, Development & Demonstration and Technology Development

activities

iii

III Details of Meetings

The Sub-Committee on Research, Development and Demonstration

(RD&D) met on 09.12.2013 and had detailed presentations and discussions

on the activities relating to RD&D in the areas of hydrogen production, its

storage & applications in power generation and vehicles based on IC engine

& fuel cell technologies. The second meeting of the Sub-Committee was held

on 03.03.2014 for the identification of thrust areas for hydrogen production, its

storage & applications in power generation and vehicles based on IC engine,

so as the Ministry may consider supporting projects in these areas. In the

third meeting held on 18.11.2014 in the Ministry of New and Renewable

Energy, New Delhi, detailed presentations and discussions were made on

hydrogen production. Based on the input received from the expert members

of the Sub-Committee and experts outside the Sub-Committee, a draft report

on Hydrogen Production was prepared. This Draft Report was presented in

the 5th meeting of the Steering Committee on Hydrogen Energy and Fuel

Cells held on 11.08.2015 in MNRE, which gave some suggestions to modify

the report. The draft report was modified incorporating these suggestions. The

Steering Committee further requested that the Chairpersons of all the five

Sub-Committees to meet and discuss uniformity of the reports and alignment

of outcome of the reports. Accordingly, the draft report was again modified

based on the suggestions given / decisions taken in the meetings of the

Chairpersons of the Sub-Committees held on 11.09.2015, 16.12.2015 and

18.01.2016.

Note: Since the Sub-Committees on different aspects (Fuel Cell

Development; Hydrogen Storage & Applications other than Transportation;

Transportation through Hydrogen fuelled Vehicles and IPR, PPP, Safety,

Standards, Awareness & Human Resource Development) of the Steering

Committee on Hydrogen Energy and Fuel Cells, covered activities relating to

Research, Development & Demonstration (RD&D) in their respective areas, it

was decided that the Sub-Committee on Research, Development &

Demonstration (RD&D) would focus only on hydrogen production.

iv

1

EXECUTIVE SUMMARY

2

3

1.0 Executive Summary

Preamble

1.1 Use of fossil fuels has become a part of daily energy needs and their

requirement is increasing with the passage of time. Consumption of fossil

fuels gives rise to the greenhouse gas emissions in the environment and

causes ambient air pollution, which have now become global concerns. This

coupled with the limited reserves of fossil fuels have encouraged and

promoted the development and use of new and renewable energy sources,

including hydrogen energy as an alternative clean fuel. The technologies for

production of hydrogen from new and renewable sources of energy are not

yet mature and the cost of hydrogen produced through new and renewable

energy sources is still very high and is not competitive to that produced from

fossil fuels. In order to meet the future energy demands in sustainable and

environment friendly manner, technologies are required to be developed for

the production, storage and applications of hydrogen in transportation sector

as well as for portable and stationary distributed & non-distributed power

generation. In some countries governments have started supporting these

efforts.

1.2 Hydrogen is an energy carrier (a secondary source of energy) and is

available in chemically combined forms in water, fossil fuels, biomass etc. It

can be liberated with the electrical or heat energy input (generated from some

primary energy source like fossil fuel, nuclear power or a renewable energy

source such as - solar, wind, hydro-electricity, etc.). Presently the agriculture

sector is the largest user of hydrogen (as nitrogenous fertilizer), with 49% of

hydrogen being used for ammonia production (Konieczny et al., 2008)

1.3 Approximately 95% of the hydrogen produced presently comes from

carbonaceous raw material, primarily of fossil origin. About 4% is produced

through electrolysis of water.

1.4 Hydrogen is also produced as a by-product in Chlor-Alkali industries.

There are around 40 such units in India, which produced nearly 66000 tons of

by-product hydrogen during 2013-14. Around 90% of this by-product

hydrogen is utilized for captive and other uses. Only a fraction of this

hydrogen is currently used for energy purposes. Around 6600 tons of this

hydrogen is still unutilized.

1.5 Hydrogen Production Technologies

a) Reforming of Carbonaceous Sources: Conventional technologies for

4

hydrogen production are: i) Steam Methane Reforming ii) Partial Oxidation,

iii) Auto-Thermal Reforming, iv) Methanol Reforming, v) Ammonia Cracking,

vi) Thermo-catalytic Cracking of Methane, and vii) Novel Reformer

Technologies. Steam Methane Reformers are commercially available for

hydrogen production. In the United States, most hydrogen (over 90%) is

manufactured by steam reforming of natural gas presently. High purity

industrial hydrogen with 99.999% purity is produced from commercial

hydrogen by pressure swing adsorption systems or by palladium gas

membranes. Technologies for coal gasification are commercially available

internationally. At national level, hydrogen is produced commercially in

fertilizer plants and petroleum refineries by reformation of natural gas. There

are extensive industry and government programs addressing to particular

technical issues for small-scale reformers, and for syngas production in the

country.

1.5.1 Compact “Fuel Cell Type” Low Pressure and Temperature Steam

Methane Reformers were developed in small sizes to produce 50 to 4000

Nm3 H2/day internationally (Halvorson, et al, 1997).These have recently been

adapted for stand-alone hydrogen production. Energy conversion efficiency

in the range of 70%-80% is possible for these units. Internationally, a novel

gasoline steam reformer with micro-channels was developed to reduce the

size and cost of automotive reformers. Another 1 kW plate reformer, a more

compact, low cost standardized design having better conversion efficiency,

and faster start-up was developed for fuel cell systems. It yielded increased

energy conversion efficiency (from about 70% to 77%) by reducing heat

losses. Its lifetime is also expected to be increased from 5 to 10 years.

1.5.2 Membrane Reactors for Steam Reforming is another promising

technology. Depending on the temperature, pressure and the reactor length,

methane is completely converted, and very pure hydrogen is produced. This

allows its operation at lower temperature and lower cost. A potential

advantage of this system is simplification of the process design and capital

cost reduction. Japan has built and tested a small membrane reactor for

production of pure hydrogen from natural gas (at a rate of 15 Nm3/h).

1.5.3 Partial Oxidation (POX) Reformer: Large-scale partial oxidation

systems have been used commercially to produce hydrogen from

hydrocarbons such as residual oil, for industrial applications. Small-scale

partial oxidation systems have recently become commercially available, but

are still undergoing intensive R&D. These reactors are more compact than a

steam reformer with efficiency of 70-80%. This technology is being used to

install a natural gas reformer filling station to supply hydrogen to fuel cell

buses and Hythane® buses at Thousand Palms, California. Several

companies are involved in developing multi-fuel fuel processors for 50 kW fuel

5

cell vehicle power plants and to develop gasoline fuel processors based on

POX technology.

1.5.4 Auto-thermal reformers combine some of the best features of steam

reforming and partial oxidation systems. Several companies are developing

small auto-thermal reformers for converting liquid hydrocarbon fuels to

hydrogen for the use in fuel cell systems. The auto-thermal reformer requires

no external heat source and no indirect heat exchangers. Heat generated by

the partial oxidation is utilized to drive steam reforming reaction. This is more

compact than conventional steam reformers, and will have a lower capital cost

and higher system efficiency than partial oxidation systems. Auto-thermal

reformers are being developed for PEMFC systems by a number of groups

1.5.5 Methanol Reformation takes place with steam at moderate

temperatures (250-350oC). These reformers have been demonstrated by

several automakers in PEM fuel cell vehicles, where methanol is stored on-

board. But no fuel cell vehicle manufacturer is currently using this technology.

The advantages are compactness, better heat transfer, faster start-up and

potentially lower cost. Internationally, units are produced for steam reforming

of alcohols, hydrocarbons, ethers and military fuels. CJB Ltd., a British

company built and tested a plate type steam methanol reformer and

integrated the fuel cell system. A multi-fuel processor was demonstrated for

pure hydrogen production via steam reforming of methanol, using a palladium

membrane and micro-reactor technology to create a portable hydrogen

source for fuel cells.

1.5.6 Ammonia Cracking: Ammonia is widely distributed in the country and

available at low cost. It is relatively easy to transport and store, compared to

hydrogen. It can be cracked at 9000C with up to 85% efficiency. Water is not

required as co-feed. A costly separation unit Pressure Swing Adsorption unit

for separating H2 and N2 would be required. Thermo-catalytic cracking of

methane is still far from commercial application for hydrogen production. The

primary issues are low efficiency of conversion and coking but relatively low

capital costs are projected.

1.5.7 Sorbent-enhanced Catalytic Steam-reforming System: Syngas,

produced using novel reformer technologies, has a substantially higher

fraction of hydrogen than that produced in a catalytic steam-reforming reactor.

Sorbent-enhanced systems are still at the demonstration stage, and show

promise for low cost. Issues to be resolved include catalyst and sorbent

lifetime and system design.

1.5.8 Hydrogen Separation through Ceramic Membrane: Globally, some

research groups are developing ceramic membrane technology for separation

6

of hydrogen from syngas. The membranes are non-porous, multi-component

metallic oxides that operate at high temperature (>700oC) and have high

oxygen flux and selectivity. These are known as ion transport membranes

(ITM). Conceptual designs were carried out for a hydrogen-refueling station

dispensing 15000 m3/day hydrogen at 350 bar. This route offers a 27% cost

savings compared to trucked-in liquid hydrogen.

1.5.9 Thermal plasma reformer technology can be used for the production

of hydrogen and hydrogen-rich gases from methane and a variety of liquid

fuels. Thermal plasma is characterized by temperatures of 3000-10000oC,

and can be used to accelerate the kinetics of reforming reactions even without

a catalyst. Plasma-reforming systems have been developed and used for

evaluating the potential of this technology for small-scale hydrogen

production. The best steam reforming results to date showed 95% conversion

of methane and projected that the power required can be reduced by about

half.

1.5.10 Hydrogen is currently produced for industrial applications by cracking

carbonaceous fossil fuels. Natural gas reforming is currently the most

efficient, economical and widely used process for production of hydrogen and

has been utilized globally for many decades in the oil refinery and fertilizer

industries. Steam reforming (SMR) has the lowest capital costs of the

hydrogen production technologies with efficiencies in the range 60%–80%.

1.5.11 In spite of efforts to produce hydrogen by processes involving solar

energy, wind energy, nuclear energy and bio-fuels, fossilized carbonaceous

resources and their products remain the most feasible feedstock in the near

term, and for commercial scale production of pure hydrogen, steam reforming

remains the most economic and efficient route.

b) Pyrolysis of Biomass and reformation of bio-oil and gaseous

products

1.5.12 Biomass is a renewable source of energy and is available almost

everywhere on the earth. Hydrogen content in biomass is roughly 6.5% by wt.

Biomass is thermally decomposed / fast pyrolysed in the temperature range of

600 - 10000C at 1-0.5 MPa in an inert atmosphere to form vapors of dark

brown bio-oil (about 85% oxygenated organics and remaining water), other

gaseous products (H2, CH4, CO & CO2) and solid products(mainly charcoal).

The bio-oil and gaseous products are then reformed to produce hydrogen.

The maximum yield of hydrogen can reach up to 90% with the use of Ni-

catalyst at 750-8500C. Alternatively, the phenolic components of the bio-oil

can be extracted with ethyl acetate to produce an adhesive/phenolic resin co-

product; the remaining components can be reformed as in the first option. The

7

product gas from both alternatives is purified using a standard Pressure

Swing Adsorption (PSA) system. National Renewable Energy Laboratory

(NREL) U.S.A. has developed a demonstration scale unit for the production of

hydrogen from pyrolysis oil by steam reformation. The pyrolysis oil is also

generated from biomass (such as peanut shells) in a fluidized bed. Slow

pyrolysis gives high char yield and is generally not considered for hydrogen

production.

c) Gasification of Renewable Biomass and its Reformation

1.5.13 Biomass gasification is a sub-stoichiometric combustion process, in

which pyrolysis, oxidation and reduction take place. Pyrolysis products

(volatile matter) further react with char and are reduced to H2, CO, CO2, CH4

and higher hydrocarbons (HHC). In this process, tar is formed, which may

produce tar aerosols and polymerized compounds. Therefore, tar formation is

undesirable. The gasifier may be so appropriately designed to reduce tar

formation. Injection of secondary air is used to reduce tar formation. Indian

Institute of Science (IISc), Bangalore has developed an open-top downdraft

gasifier, in which effects of various parameters like, equivalence ratio (ER),

steam-to-biomass ratio (SBR) residence time- temperature on efficiency are

studied. Ni-based catalysts and alkaline metal oxides are used as gasification

catalysts to improve gas product quality and conversion efficiency. The

syngas yield increased from 353 g per kg of biomass to 828 g per kg of

biomass by varying the pyrolysis temperature from 600 - 10000C.

1.5.14 Internationally, many countries are involved in the development of

biomass gasification technology. The University of British Colombia, Canada

is working on fluidized bed gasification and sorbent based hydrogen

separation unit. The Gas Technology Institute (GTI), Chicago is working on a

the demonstration project for direct generation of hydrogen from a down draft

gasifier using a membrane reactor, The Energy Research Centre of the

Netherlands has developed a pilot plant scale unit of 800 kW th capacity based

on gasification technology. The Technical University of Vienna is developing a

Fast Internally Circulating Fluidized-bed (FICB) technology for steam-blown

gasification of biomass in cooperation with Austrian Energy and Environment

agency. A combined heat and power (CHP) plant (8MW) is in operation since

2002 in Güssing, Austria. Later on, Synthetic Natural Gas (SNG) production

was also demonstrated in a methanation unit, which took a 1 MW SNG

slipstream from the Güssing plant. The targeted production cost of hydrogen

through this method is around US$ 2.5 to 3.5 /kg of hydrogen at large scale.

The Biomass Gasification project of Gothenburg, Sweden aims to construct a

synthetic natural gas (SNG) plant.

8

1.5.15 With the development of fuel cell systems in the country, MNRE

focuses on the generation of hydrogen rich syngas through thermo-chemical

conversion of biomass and its purification to fuel cell grade. IISc has recently

concluded a project addressing these aspects. This encouraged work on the

development of a prototype system to generate hydrogen rich syngas using

oxy-steam gasification. The entire process has been optimized to generate a

maximum of about 100 g of hydrogen per kilo gram of biomass. Syngas

composition, hydrogen yield and performance parameters have been

monitored by varying steam to biomass ratio and equivalence ratio. Results

show that using dry biomass with oxy-steam improves the hydrogen yield,

efficiency and syngas with lower heating value (LHV) compared to direct

usage of wet biomass with oxygen. With the current experience of using

biomass, about 70 g of pure hydrogen can be obtained per kg of biomass,

which results in about 15 kg of biomass for every kg of hydrogen generated.

d) Electrolysis of Water

1.5.16 Hydrogen can be generated through electrolysis of water. The water

electrolysis can be carried out in three different ways viz., alkaline water

electrolysis, acidic water (polymer electrolyte membrane based) electrolysis

and high temperature ceramic membranes (solid oxides membranes) water

electrolysis. Polymer electrolyte membrane (PEM) based water electrolysers

are more advantageous than conventional water-alkali electrolysers due to

their ecologically safe nature, production of hydrogen with high purity

(>99.99%) and possibility to produce at high pressure.

1.5.17 The alkaline water electrolysis is a matured technology and is

commercially available in megawatt range. It has a stack life is <90,000 h and

system life of 20-30 years, energy requirement of around 6 kWh per Nm3

hydrogen and efficiency of 60-70%. In the case of PEM based water

electrolysers stack life is <20,000 h and the system life is estimated to be

around 10-20 years. These electrolysers are smaller, cleaner and more

reliable systems than other electrolysers. Alkaline electrolysers are less

expensive than PEM electrolysers due to use of non-noble metal (nickel

based) catalysts, but consume more electricity. The major challenges of

these electrolysers are related to corrosion and poisoning of the electrolysers

by inadvertent incursion of CO2. The largest existing alkaline electrolysis

plants are 160 MW plant in Aswan, Egypt and 22 MW plant operating in Peru

(pressurized operation). The Brown Boveri electrolyser can produce

hydrogen at a rate of about 4-300 m3/h.

1.5.18 The PEM water electrolyser is being deployed for the applications,

where cost is a secondary issue. The membrane material for these

electrolysers is Nafion from DuPont, USA. Besides Du Pont, Asahi Glass,

9

Dow Chemicals and others have also developed similar membranes either

based on fluorinated or non-fluorinated polymers, which are commercially

available. The fluorinated polymers have shown good performance for >5000

hours of operation in the fuel cells. However, there are other issues related to

its operation such as increase of cross-permeation of gases with increase in

pressure. As of now small and medium range PEM water electrolysers are

available for laboratory use and other applications. Currently available PEM

water electrolyser systems have a hydrogen production rate that varies from

0.06 to 75 Nm³/h whereas alkaline electrolysers have reached the hydrogen

production rate of 760 Nm³/h.Siemens, FRG plans to build an electrolyser

system to store wind power as hydrogen. The system will have a peak rating

of up to 6 MW.

1.5.19 High temperature water electrolysis uses solid oxide electrolyte and

offers advantage over alkaline and PEM electrolysers in terms of higher

efficiency and lower capital costs. Solid oxide membranes are prepared from

calcium and yttrium stabilised zirconium oxide. These electrolysers are

operated at high temperatures (900–1000°C), which reduces the consumption

of electricity for production of hydrogen by about 30% in comparison to other

electrolysis processes at room temperature. Electricity consumed is about

2.6-3.5 kWh/Nm3 of hydrogen produced.

1.5.20 The Bhabha Atomic Research Centre (BARC), Mumbai has developed

water electrolysers with high current density (4500 A/m2) based on

indigenously developed advanced electrolytic modules incorporating porous

nickel electrodes. A portable electrolyser of 1.5 Nm3/h hydrogen production

capacity and large units of capacities 10 and 30 Nm3 /h hydrogen production

have been developed. BARC has also planned to develop high temperature

steam electrolyser of 1.0 Nm3/h hydrogen production capacity for technology

demonstration purposes. CSIR-CECRI has developed activated nickel

electrode for alkaline electrolyser. PEM water electrolyser of capacity 1.0 and

5.0 Nm3/h were also developed during 2012 and demonstrated with energy

consumption of about 5.75 kWh/Nm3of hydrogen at 5-10 bar pressure. These

technologies have been transferred to M/s. Eastern Electrolysers, New Delhi

for further development. In addition, CSIR-CECRI has also demonstrated

solar power integrated PEM based water electrolyser system of 0.5 Nm3/h

capacity in 2012.The SPIC Science Foundation (SSF), Chennai has

developed PEM based water electrolysers for hydrogen production at the

rates of 0.5 and 1 Nm3/h. In these electrolysers titanium plate was platinised

and used as bipolar plate. The SSF has also developed and demonstrated a

PEM based water electrolyser system with the hydrogen production capacity

of 60.0 lit/h using methanol as the depolariser. The energy consumption for

hydrogen production was 2.0 kWh/Nm3.The Institute of Science and

Technology, JNTU, Hyderabad has developed PEM based water electrolyser

10

to produce hydrogen at the rate of 36 L/h using Nafion membrane. The Centre

of Fuel Cell Technology, Chennai (a project of International Advanced

Research Centre for Powder Metallurgy, Hyderabad) has developed and

demonstrated a 1.0 Nm3/h hydrogen production capacity electrolyser using

similar concept but with much lower energy consumption of 1.40kWh/Nm3. It

also demonstrated for the first time the use of carbon based materials in its

construction and thus redcuing the capaital cost tredomnously. M/s. MVS

Engineering Ltd, New Delhi are offering PEM water electrolyser technology on

turnkey basis in partnership with Proton Onsite (USA) for hydrogen

generation. Recently, such a system has been installed at the Indian Oil’s

R&D Centre, Faridabad. A number of other companies are also reported to

have commercialised alkaline water electrolyser for various industrial

applications. In general, the production of hydrogen through electrolysis of

water is a highly energy intensive (4.5-6.5 kWh/Nm3). High energy

consumption coupled with high capital investment is the reason, why water

electrolysis technology is not preferred in India for commercial purposes.

1.5.21 Acid and alkali based solid polymer electrolytes have been

developed. Alkali based electrolytes use non-noble catalysts, but face

challenges such as chemical stability in the electrochemical system. The

electrolysers using acid based solid polymer electrolyte may be deployed on a

small scale for distributed hydrogen production systems both in industry as

well as remote areas for different applications. It is suggested to setup

hydrogen production plants based on presently available technology, which

can be manufactured in India and then conventional electrolyser may be

replaced by the SPE based electrolysers in a phased manner. This will ensure

the successful deployment of technology in the times to come. The estimated

cost per kg of hydrogen is about $ 8.94, when produced on a 1 MW level.

1.5.22 The strategy to bridge the gap may be planned by identifying projects

and the institutions to work in the relevant specialized areas and demonstrate

their prototypes. Foreign collaborations may be solicited in specific areas.

After successful demonstration of the prototypes, the R&D institutions may

work with the industry through PPP Model for commercialization of the

technology. Except the electrochemical stack, couple of Indian PSUs have

core strength for manufacturing majority of subsystems and are very much

capable in system engineering. Imported electrolyser stacks in different

combinations may also be used and integration can be carried in the country.

e) Bio-Hydrogen Process

1.5.23 The bio-hydrogen production may be an economical way of hydrogen

production on the ground that the process takes place at ambient temperature

and atmospheric pressure; while other processes are carried out at higher

11

temperatures & pressures. The major biological processes for hydrogen

production are bio-photolysis of water by algae (if the algae is deprived of

sulphur, it will switch from the production of oxygen, i.e. normal

photosynthesis, to the production of hydrogen), dark and photo-fermentation

of organic materials, usually carbohydrates by bacteria. One of the major

problems faced by photo-fermentative reactors is the light shading effect

generated by accumulation of pigment in the photo-fermentative microbes.

Moreover, the rate of hydrogen production in bio-hydrogen reactors is also

considerably low when compared with dark fermentation. Sequential dark and

photo-fermentation process is a new approach for bio-hydrogen production.

Dark fermentation reactions do not require light energy, so they are capable of

constantly producing hydrogen from organic compounds present in

wastewater throughout the day and night. Among all the biological hydrogen

production processes, dark fermentation shows highest hydrogen production

rates. This process holds promise for commercialization. Carbohydrate rich,

nitrogen deficient solid wastes such as cellulose and starch containing

agricultural and food industry wastes and some food industry wastewaters

such as cheese whey, olive mill and bakers’ yeast industry waste water can

be used for hydrogen production by using suitable bio-process technologies.

Utilization of aforementioned wastes for hydrogen production provides

inexpensive energy generation with simultaneous waste treatment. A

prototype hydrogen bioreactor using waste as a feedstock is in operation at

Welch's grape juice factory in North East Pennsylvania, USA. Another two-

stage process where bio-hydrogen production process was integrated with

bio-methanation is also being considered as a feasible option for improvement

of gaseous energy recovery. This mixture of bio-hydrogen and bio-methane

may be named as “hymet”.

1.5.24 Major contributors in biohydrogen production research are from United

States of America, Canada, Malasiya, Indonesia, Thailand, China and India.

Different microbes have been discovered in different parts of the world, each

having unique hydrogen production ability. Shri AMM Murugappa Chettiar

Research Centre, (MCRC), Chennai was involved in the development of

hydrogen production through biological process from sugar and distillery

wastes (effluents of M/s. E.I.D. Parry Ltd., at Nellikuppam, Tamilnadu). The

Center has designed and developed a 125 m3 bioreactor, which produced

18,000 liters of gas per hour with about 60% hydrogen mixed largely with CO2

and CO. Mesophilic and thermophilic species were identified for hydrogen

production. Indian Institute of Technology Kharagpur and Indian Institute of

Chemical Technology, Hyderabad are currently setting up bio-reactors of

10m3capacity each based on distillery effluent and kitchen waste respectively

and are expected to provide hydrogen yield of 30-50 m3 / day. For bio-

hydrogen to be considered as renewable energy source, it should be

produced from renewable raw materials like waste materials. Internationally

12

very few studies are available on commercial level units for bio-hydrogen

production. Integration of bio-hydrogen with fuel cell was first mooted in 2012.

This concept still needs a serious consideration since this technology is

capable of producing hydrogen in a decentralized manner.

1.5.25 Hydrogen can be recovered equivalent to only 20 to 30 % of total

energy through dark fermentation and therefore has limitations in

commercialization, even though this process can be integrated with photo-

fermentation. Theoretically, 12 moles of hydrogen /mole of glucose can be

recovered from integrated dark and photo fermentation reactors but due to

scaling up problem of photo-fermentation such two-stage process cannot

commercialised. The dark fermentation for hydrogen production can be

commercialised, if it is integrated with biomethantion process. The spent

media of the dark fermentation is rich in volatile fatty acids and would be an

ideal substrate for methanogens. The integration of these two processes

might lead to 50-60% gaseous energy recovery. Most attractive point of such

process is that the reactor used for hydrogen production could be used for

bio-methanation also, thus separate reactors are not required. Biohymet

production could be envisioned as renewable source of energy only, when it

would be produced from renewable sources.

f) Thermochemical splitting of water

1.5.26 Water can be dissociated at very high temperatures into hydrogen and

oxygen through thermochemical splitting of water. A catalyst is required to

make the process operate at feasible temperatures. The required energy can

be either provided by nuclear energy or by solar energy, or by hybrid systems

including solar and nuclear energy. More than 356 thermo-chemical cycles

have been conceived which can be used for water splitting. Around a dozen

of these cycles such as the iron oxide cycle, cerium(IV) oxide-cerium(III) oxide

cycle, zinc-zinc oxide cycle, sulfur-iodine cycle, copper-chlorine cycle and

hybrid sulfur cycle are under research/in testing phase. The iodine-sulphur (I-

S) cycle is one of the most promising and efficient thermo-chemical water

splitting technologies for the mass production of hydrogen, on which BARC,

Trombay, Mumbai is working.

1.5.27 The I-S closed loop glass system has been operated continuously for a

period of 20 hours at hydrogen production rate of 30 Lph. India is the 5th

country to achieve I-S closed loop operation in glass system, after USA

(1980), Japan (2004), China (2010) and South Korea (2009). USA aims to

demonstrate commercial scale production of hydrogen using nuclear energy

by 2017. European Union started working in this direction in 2004 with the

objective to evaluate the potential of thermo-chemical processes, focusing on

the I-S cycle which is to be compared with the Westinghouse hybrid (HyS)

13

cycle in view of the 2015 target for reduction of CO2 emissions from fossil

fuels by more than 25% and hydrogen production cost of less than €2/kg. It

has been found that hydrogen production costs based on small plants is most

favorable using solar energy, while nuclear energy based plants are most

economical at high power levels (> 300 MW th); hybrid systems may have their

niche in the midrange of 100 to 300 MW th. Canada is investigating copper–

chlorine family of thermo-chemical cycles with energy provided by the

Canadian Super Critical Water Reactor and use of direct resistive heating of

catalysts for SO3 decomposition in the I-S process. Japan has recently

initiated R&D activities on the thermo-chemical cycles based on the UT-3 and

I-S processes for hydrogen production and successfully achieved the

operation of a bench-scale facility for hydrogen production at the rate of 30

Nl/h in a continuous closed I-S cycle operation over one week. While the

efficiency was only ~10% for the bench-scale plant, the goal for the pilot plant

is ~40%. In 2005, Japan have already initiated the activity to design and

construct a pilot plant for hydrogen production at the rate of 30 Nm3/h under

the simulated conditions of a nuclear reactor.

1.5.28 The Republic of Korea has targeted for 25 % (3 Mt/year) of the total

hydrogen to be supplied by advanced 50 nuclear reactors by 2040. Korea

launched its nuclear hydrogen program in 2004 targeting (i) generation of

hydrogen for fuel cell applications for electricity generation, passenger

vehicles, and domestic power and heating, and (ii) lowering hydrogen costs

and improving efficiency of the related processes. Under this programme an

underground VHT reactor of 200 MW thermal output is to be coupled with an

I-S cycle to generate hydrogen from water. In 2005 People’s Republic of

China initiated work on a demonstration project on ‘High Temperature Reactor

– Pebble Module’. Both the I-S thermo-chemical cycle and high temperature

steam electrolysis are selected as the potential processes for nuclear

hydrogen production. The target has been set for commercialization of

nuclear hydrogen production by 2020.

1.5.29 The Bhabha Atomic Research Centre has successfully demonstrated I-

S process in closed loop operation in glass/quartz material in the laboratory. It

is further planned to demonstrate closed loop operation in metallic

construction. Other institutes / organisations will also be roped in depending

upon their capabilities. Their broad plan is:

(i) Design and Demonstration of Atmospheric pressure operation all

Metal closed loop system (AMCL).

(ii) High pressure operation Bunsen reactor system has been designed

and its commissioning is underway.

(iii) Design and demonstration of high pressure Sulfuric acid

decomposition system.

14

(iv) Design and demonstration of Hydriodic acid distillation and

decomposition system.

(v) Integration of all three high pressure systems to demonstrate, High

pressure closed loop process.

1.5.30 The ONGC Energy Centre (OEC) started working on the three

thermochemical processes such as Cu-Cl closed loop cycle, I-S closed loop

cycle and I-S open loop cycle at engineering scale and all these processes

will be compared before taking-up at the commercial level. In view of

expensive and corrosive nature of materials used in these processes, OEC

has planned to study and evaluate alternative materials. New plants may

then be designed based on this evaluation of the alternative materials.

CSMCRI, Bhavnagar has been involved in the ‘development of membranes’;

IIP Dehradun is engaged in the ‘development of partially open-loop I-S cycle

involving H2S incineration and experimental studies on Bunsen Reaction & HI

decomposition’; IIT-Delhi is working on “prolonged stability tests of catalysts

for HI decomposition reaction of I-S cycle.

1.5.31 Photo-catalytic and photo-electrochemical routes for hydrogen

production are also being explored globally by several research groups. In

India also some groups, namely, Indian Institute of Chemical Technology,

Hyderabad; Institute of Minerals and Materials Technology, Bhubaneswar;

Yogi Vemana University, Kadapa; SRM University; Kancheepuram, Shiksha

‘O’ Anusandhan University, Bhubaneswar and Centre for Materials for

Electronics Technology, Pune are active in this area. Efforts are being made

to come out with effective and robust photo-catalysts and photo-

electrocatalysts, electrode materials and materials for reactors. Till date no

large scale unit has been successfully designed and demonstrated.

Concerted intensive efforts, however, are required to generate basic

information and knowhow to take this area to the production for decentralized

applications.

1.5.32 In photo-electrochemical water splitting, hydrogen is produced from

water using sunlight and specialized semiconductors called photo-

electrochemical materials. The Institute of Minerals and Materials Technology

Bhubaneswar developed functional hybrid nano-structures for photo-

electrochemical water splitting. The different photo-catalytic materials were

developed for hydrogen production through water splitting. The developed

materials yielded hydrogen e.g. 800-1000 mg hydrogen /batch with CdS

photo-electrodes and CdS nano-crystal powder photo-catalysts, 4087 µmol

hydrogen/h/g with 0.28 wt% Poly (3-hexylthiophene-2,5-diyl) (P3HT) modified

CdS and 11,901 µmol hydrogen/h/g with CdS-NaNbO3 core-shell nano-rods.

Thus, CdS-NaNbO3 core-shell nano-rods was found to give maximum

hydrogen production.

15

g) Other Technologies

1.5.33 Presently, Hydrogen Production by non-thermal plasma assisted direct

decomposition of hydrogen sulphide is at research and development stage

and no commercial technology is available globally. Among the several

techniques tested for the production of hydrogen, Idemitsu Kosan Hybrid

(IKC) electrolysis process consumes 3.6 kWh/Nm3 hydrogen, whereas steam

reforming of methane, (the traditional approach for hydrogen production)

demands still higher energy of 4.3 kWh/Nm3 hydrogen. 40% conversion of

hydrogen sulphide by thermal decomposition can be achieved at temperature

~ 1500K. Most of the research in this area in the country has been focused

on catalytic/ photocatalytic decomposition of hydrogen sulphide. Hydrogen

sulphide under visible light to generate hydrogen is an attractive route of solar

energy conversion, because hydrogen is 100% environmentally clean fuel in

its cycles of generation and utilization. The Indian Institute of Technology

Hyderabad developed the process of non-thermal plasma assisted direct

decomposition of hydrogen sulphide into hydrogen and sulphur. Hydrogen

production of 0.5 litre/minute was achieved in the laboratory. The reaction

conditions can be still improved to decrease the energy consumption.

1.5.34 For the photo-splitting of hydrogen sulphide into hydrogen, extensive

work has been carried out for the development of ultraviolet driven

photocatalyst for water and hydrogen sulphide splitting. There is need to

develop prototype batch photo-reactor for hydrogen production from hydrogen

sulphide using solar energy and their field trials using gas emitted at refinery

site. Internationally, many groups in Japan, Korea, U.S, Europe are working

on development of active photo-catalysts for hydrogen generation under

visible light irradiation. The National Institute of Advanced Industrial Science

and Technology, Japan demonstrated first time in 2001 direct splitting of

water by visible light over an In1.xNixTaO4photocatalyst. Nationally, a few

groups are working on photocatalytic splitting of water and hydrogen and

hydrogen sulphide into hydrogen under visible light. BARC is working on

photocatalytic degradation of nuclear waste as well as water purification. IISc,

Bangalore is working on TiO2 based photocatalysts for organic waste

degradation. IITs, Mumbai and Madras, CECRI, Karaikudi, IICT, Hyderabad

and some universities in India are working on photodecomposition of organic

pollutants. The Centre for Materials for Electronics Technologies (C-MET),

Pune is also working on hydrogen generation by photocatalytic decomposition

of toxic hydrogen sulphide and achieved hydrogen production from hydrogen

sulphide at the rate of 8182.8 and 7616.4 µmol/h/g obtained from

nanostructured ZnIn2S4 and CdIn2S4, respectively in presence of sunlight. This

design is useful for continuous operation at large scale.

16

1.6.0 Suggested Action Plan

1.6.1 Based on the gap analysis undertaken between international and

national state of art of technologies and recommendations to fill the gap by

undertaking the projects as classified in the three broad categories: (a)

Mission Mode (for the technologies, which are mature or near maturity for

commercialization and with the participation of the industry); (b) Research &

Development Mode (for the technologies, which are at the stage of prototype

development, their demonstration as a proof of concept and preferably with

Industry participation); and (c) Basic / Fundamental Research Mode (for

advanced research on new materials and processes), the Action Plan for

hydrogen production in the country has been devised as following:

1.6.2 The unutilized (around 6600 tonnes) by-product hydrogen from the

Chlor-Alkali Units / Refineries may be used directly for the generation of

power / in transportation applications (vehicles) based on IC engine

technology. This hydrogen may further be purified (if required) for stationary

power generation and on-board application in vehicles / material handling

systems based on fuel cell technology. To utilize this hydrogen requisite

power generating system / purification unit / compression system to fill

cylinders for on-board application of hydrogen in vehicles / material handling

vehicles (based on fuel cell technology) need to be set-up. The activity is to

be completed by 2018.

1.6.3 Hydrogen has been produced from the conventional sources i.e.

carbonaceous fuels like natural gas, coal etc. Hydrogen production by

electrolysis, methanol or ammonia cracking is preferred for small, constant or

intermittent requirements of hydrogen in food, electronics and pharmaceutical

industries, while for larger capacities steam reforming of hydrocarbons /syn

gas is preferred. Renewable-based processes like solar- or wind-driven

electrolysis and photo-biological water splitting hold great promise for clean

hydrogen production; however, advances must still be made before these

technologies can be economically competitive. Thus, hydrogen production

may be continued from the conventional (carbonaceous) fuels through the

most competitive process namely auto-thermal reforming (steam reforming

and partial oxidation) process till the technologies for hydrogen production

from renewable sources become economically competitive. Scaling-up of the

process of catalytic decomposition of natural gas for the production of H-CNG

for the use in H-CNG fuelled vehicles (up to 2019), Development &

demonstration of hydrogen production by Auto-thermal Process (up to 2020)

and Basic / Fundamental Research for dissociation of gaseous hydrocarbon

fuels to hydrogen using solar energy (up to 2022) may be carried out.

17

1.6.4 Biomass has been identified as potential source of renewable energy

for hydrogen production. Biomass is gasified to hydrogen rich syngas, which

may be reformed and purified to yield pure / near pure hydrogen. The

technology of oxy-steam gasification of biomass for hydrogen products has

been developed at a small pilot scale (2 kg/h) by the Indian Institute of

Science, Bangalore. This may be promising technology for distributed

hydrogen production. However, there are challenges associated with

purification of hydrogen and scaling up. Research and development for

hydrogen production by gasification of biomass may, therefore, be carried out

including demonstration of technology at pilot scale (up to 2020).

1.6.5 Pure hydrogen may be obtained by electrolysis for fuel cells

applications. The electrolyser system consists of various sub-systems. India is

capable in system engineering and has core strength for manufacturing

majority of sub-systems except electrochemical stack. Imported electrolyser

stacks may be used with the indigenously developed sub-systems. The

Institutions / Industry may be identified to work in PPP Model for

commercialization of the balance of plant and simultaneously, the technology

for the production of stack may be procured or developed indigenously. Solid

polymer electrolyser (SPE) with 20,000 hours of operation is desirable and

may have membranes based alkaline water electrolysis system integrated

with solar photovoltaic system. For the immediate availability of hydrogen

onsite, hydrogen may be produced by deploying solar energy powered Acid /

Alkali based electrolysis systems based on available technology.

Simultanously, development of (i) electrolysers based on indigenous acid

based SPE (ii) alternate alkaline membrane up to 2018 (iii) alkaline 1 & 5

Nm3/h high temperature steam solid polymer water electrolyser (up to 2020)

may be done and demonstrated and replaced old systems by the newly

developed systems. Hydrogen production system by splitting water using

renewable energies such as solar energy, wind energy and hybrid systems

including electrolysis, photo-catalysis and photo-electro-catalysis may also be

developed and demonstrated(up to 2022).

1.6.6 Hydrogen may be produced through dark-fermentation followed by the

photo- fermentation of solid waste from agriculture & food industry and liquid

waste from food industry. The integrated process is difficult to commercialise

in view of the problems associated with the photo-fermentative reactors.

Therefore, dark fermentation followed by bio-methanation may be studied,

which can recover 50 - 60% gaseous energy from the waste. Only one reactor

may be required for both processes – firstly, hydrogen production and

subsequently, bio-methanation. The mixture of hydrogen and methane, so

produced, is known as bio-hymet. The production of bio-hymet could be

envisioned as renewable source of energy. This activity has been proposed

to be taken up in Research, Development and Demonstration Mode up to

18

2019. Energy balance and process economic aspects may also be studied.

Biological hydrogen production projects may also be taken up for

demonstration in niche areas.

1.6.7 Another path for hydrogen economy has been suggested by the

integration of fuel cell system with the bio-hydrogen production system. Such

setups may be put strategically near to those places where supply of

feedstock is easily available in adequate quantities. The electricity generated

by such system may be used to electrify villages in a decentralized manner. It

is suggested to take-up such activities in Mission Mode up to 2022.

1.6.8 The Bhabha Atomic Research Centre is engaged in the development

of I-S technology in-house. This process in closed loop operation has been

successfully demonstrated in glass/quartz reactor. Further, it has been

planned to demonstrate closed loop operation of I-S in metallic reactor.

ONGC Energy Centre is also working on I-S process in collaboration with IIT-

Delhi, ICT Mumbai and CECRI, Karaikudi on both I-S open & closed loop and

Cu-Cl cycles. Hydrogen generation @ 27 LPH has been achieved through

Cu-Cl process under specified operating conditions. It is suggested to

continue these activities using solar / nuclear heat in Mission Mode up to

2022.

1.6.9 Hydrogen production by water splitting through photolysis using solar

energy may be undertaken upto 2022 in Mission Mode.

1.6.10 Other innovative method for hydrogen production, like hydrogen

production by non-thermal plasma assisted direct decomposition of hydrogen

sulphide, Photo-splitting of Hydrogen Sulphide including developmental effort

for reduction in energy consumption for hydrogen production (up to 2022).

1.6.11 The total requirement of budget would be around Rs.285 Crore upto

2022.

1.7 Financial Projections for the Mission Mode, Research and

Development Mode and Basic / Fundamental Research Mode projects are

given as under:

19

S. No.

Name of Project Estimated Cost Rupees in

Crore

A. Mission Mode Projects

1 Setting-up of purification unit / compression system to fill cylinders for power generating system / on-board application of hydrogen in vehicles / material handling vehicles (based on fuel cell technology) to utilize surplus hydrogen from the Chlor-Alkali Units / Refineries (up to 2019).

20

2 Scaling-up of the process of partial reforming of natural gas to produce H-CNG for H-CNG fuelled vehicles (up to 2019)

40

3 Development and demonstration of biological hydrogen production from different kinds of wastes on bench scale, pilot scale and commercial production (up to 2022).

20

4 Hydrogen production by water splitting through photolysis using solar energy (up to 2022).

40

5 Demonstration of closed loop operation of I-S in metallic reactor and both I-S open & closed loop process and Cu-Cl cycle using solar / nuclear heat in Mission Mode (up to 2022).

50

Sub-Total A 170

B. Research and Development Projects

6 Hydrogen production by auto-thermal process (up to 2020)

20

7 Hydrogen production by gasification of biomass including demonstration of technology at pilot scale (up to 2020)

10

8 Development and demonstration of electrolyser based on indigenous acid based SPE and alternate alkaline membrane and its deployment to replace old systems (up to 2019).

10

9 Development and demonstration of alkaline 1 & 5 Nm3/h high temperature steam solid polymer water electrolyser and its deployment to replace old systems (up to 2020)

10

10 Development & demonstration of efficient alkaline water electrolyser (upto 2018)

10

11 Development and demonstration of hydrogen production by splitting water using renewable energies such as solar energy, wind energy and hybrid systems including electrolysis, photo-catalysis and photo-electro-catalysis (up to 2022)

10

12 Hydrogen production by reformation of bio-oil obtained from fast pyrolysis of biomass (up to

5

20

2022).

13 Development of technology for production of syn-gas (CO+H2) and hydrogen from reformation of natural gas / biogas using solar energy (up to 2022).

5

14 Integration of large capacity electrolysers with wind / solar power units, which is not in a position to evacuate power to grid, for generation of hydrogen and its storage (up to 2022).

5

Sub-Total B 85

C. Basic / Fundamental Research Projects

15 Dissociation of gaseous hydrocarbon fuels to hydrogen using solar energy (up to 2022)

10

16 Other innovative method for hydrogen production like hydrogen production by non-thermal plasma assisted direct decomposition of hydrogen sulphide, Photo-splitting of Hydrogen Sulphide including developmental effort for reduction in energy consumption for hydrogen production(up to 2022)

20

Sub-Total C 30

Grand Total

285

21

ACTIVITIES ON HYDROGEN PRODUCTION

MMP: Mission Mode Projects; RD&DP: Research & Development Projects; B/FRP: Basic / Fundamental Research Projects

Sl.

No. Category of Projects

Time Frame (Year) Financial

Outlay

(Rs. in Crore) 2016 2017 2018 2019 2020 2021 2022

1

Mission Mode Projects

20

40

20

40

50

Setting-up of purification unit / compression

system to fill cylinders to utilize surplus

hydrogen from the Chlor-Alkali Units /

Refineries

Scaling-up of the process of partial reforming of

natural gas for the production of H-CNG

Demonstration of closed loop operation of I-S in metallic reactor and both I-S open & closed loop process and Cu-Cl cycle using solar / nuclear heat

SUB-TOTAL 170

Development and demonstration of biological hydrogen production from different kinds of wastes

Phase I Bench Scale

Phase II Pilot Scale

Phase III Commercial Production

Hydrogen production by water splitting through photolysis using solar energy

22

2

Research, Development

& Demonstration

20

10

10

10

10

10 5

5 5

Hydrogen production by gasification of biomass including

demonstration of technology at pilot scale

Development, and demonstration of

electrolyser with indigenous acid based SPE &

alternate alkaline membrane and its

deployment to replace old systems

Development and demonstration of alkaline 1 & 5 Nm3/h high temperature

steam solid polymer water electrolyser and its deployment to replace old

systems

Hydrogen production by Auto-thermal Process

Development of technology for production of syn-gas (CO+H2) and hydrogen from

reformation of natural gas / biogas using solar energy.

Integration of large capacity electrolysers with wind / solar power units, which is not in a

position to evacuate power to grid, for generation of hydrogen and its storage

SUB-TOTAL 85

Development and demonstration of Hydrogen production by splitting water using

renewable energies

Hydrogen production by reformation of bio-oil obtained from fast pyrolysis of biomass

Development & demonstration of

efficient alkaline water electrolyser

23

3.

Basic / Fundamental

Research Projects

10

20

Other innovative method for hydrogen production like hydrogen production by non-

thermal plasma assisted direct decomposition of hydrogen sulphide, Photo-splitting of

Hydrogen Sulphide including developmental effort for reduction in energy consumption

for hydrogen production

SUB-TOTAL 30

GRAND TOTAL 285

Dissociation of gaseous hydrocarbon fuels to hydrogen using solar energy

24

25

INTRODUCTION

26

27

2.0 Introduction

2.1 Human being’s dependence on fossil fuels has made a deep impact on

its reserves and natural climate. This has led to exhaustion of fossil fuels,

emission of pollutants, and greenhouse gases responsible for global warming.

It has been recognized that the crude petroleum oil output by the Organisation

of the Petroleum Exporting Countries (OPEC) would not be able to meet the

energy demands beyond 2045. To address the above issues, hydrogen is

considered as one of the potential energy carrier for the future that is not only

clean but also environmentally sustainable. Hydrogen may replace petrol and

diesel used in the automobiles and even coal for large scale power

generation. Presently, hydrogen is produced for non-energy applications and

‘quantum increase’ in hydrogen production will be required to enable its mass

scale utilization as a fuel. To have sustainable hydrogen production, the

energy and raw materials needed for this purpose ought to be renewable in

nature. There are various methods which may be employed for generating

hydrogen from renewable and non-renewable resources. However, the

challenge lies in the production of hydrogen in a cost effective manner. As per

US DOE, more than 50 million tonnes of hydrogen was produced globally in

2010, of which 46.3% was consumed for petroleum recovery and refining;

44.5% for ammonia production; 3.7% for methanol production; 2.0% for metal

production and fabrication; 1.5% for electronics; 1.0% for food industry and

1.0% for other applications. About 95 % of the current hydrogen requirements

are produced through fossil fuel sources. Currently, the agricultural sector is

the largest user of hydrogen in the form of nitrogenous fertilizers, with 49% of

hydrogen being used for ammonia production. Being a clean energy source,

its future widespread use as fuel is likely to be in the transport and also in

distributed power generation sectors. Hydrogen may indeed emerge to be a

turning point for our nation, which is dependent heavily on the imported

petroleum crude and natural gas for meeting its energy needs. Development,

demonstration and commercialization of appropriate hydrogen production

technologies and systems are, therefore, essential in the country, since these

have advanced significantly world over.

2.2 Molecular hydrogen is not available on the earth in convenient natural

reservoirs. Most hydrogen on the earth is bonded to oxygen in water and to

carbon in live or dead and/or fossilized biomass. Currently manufacture of

elemental hydrogen requires consumption of energy generated from a fossil

or alternative sources. It produces carbon dioxide. Decomposition of water

requires electrical or heat input, generated from some primary energy source

(fossil fuel, nuclear power or a renewable energy- solar, wind, hydro-

electricity, etc.). The energy provided by the energy source essentially

provides all of the energy that is available in the hydrogen fuel.

28

2.3 Hydrogen may be produced from a variety of carbonaceous feed-

stocks and/or water using a variety of technologies. Coal, natural gas,

petroleum fractions and biomass can be converted to hydrogen through

pyrolysis / gasification and reforming using several technologies like steam

methane reforming, partial oxidation / auto-thermal reforming. About 95 % of

the current hydrogen requirements is met from fossil fuel sources.

2.3.1 Steam Methane Reforming (SMR) is the most common, well-

developed and fully commercialised process. It is the least expensive method

of producing hydrogen; almost 48% of the world’s hydrogen is produced from

SMR. The reforming reaction between steam and hydrocarbons is highly

endothermic and is carried out in presence of specially formulated nickel

catalyst contained in vertical tubes situated in the radiant section of the

reformer. The SMR process is popular because natural gas, commonly used

feedstock has high hydrogen content (four hydrogen atoms per carbon atom)

and distribution network for the natural gas already exists. The simplified

chemical reactions are:

CH4 + H2O = CO + 3H2 ∆ H = + 206 kJ/mol (for methane)

CO + H2O = CO2 + H2 ∆ H = - 41 kJ/mol (CO shift reaction)

The Pressure Swing Adsorption (PSA) purification unit separates

hydrogen from mixture of product gases by adsorption of CO, CO2 and CH4.

This process is commonly used to supply large quantities of hydrogen gas to

oil refineries, and ammonia and methanol plants.

Cost of hydrogen production through SMR technology is highly

dependent on the scale of production. Large capacity modern SMR hydrogen

plants have been constructed with hydrogen generation capacities exceeding

480,000 kg hydrogen/day. These large hydrogen plants typically are co-

located with the end users in order to reduce hydrogen gas transportation and

storage costs. In addition, SMR technology is also scalable to smaller end-use

applications. SMR can also be applied to other hydrocarbons such as ethane

and naphtha. Heavier feed-stocks, however, cannot be used, because they

may contain impurities and the feed to the reformer must be in vapour form.

Other processes such as partial oxidation (POX) are more efficient with higher

hydrocarbons.

2.3.2 Hydrogen production from coal gasification is also a well-established

commercial technology, but is only competitive with SMR, where oil and/or

natural gas are expensive. Three primary types of gasifiers are used: fixed

bed, fluidized bed, and entrained flow. Because there are significant coal

reserves in many areas of the world, coal could replace natural gas and oil as

29

the primary feedstock for hydrogen production. However, this technology has

environmental impacts (e.g., feedstock procurement) that may prove to be a

significant impediment in the future.

2.3.3 Non-catalytic partial oxidation of a hydrogen-rich feedstock (such as

natural gas, coal, residue oil, petroleum coke, or biomass) is another pathway

for hydrogen production. With natural gas as a feedstock, the partial oxidation

process typically produces hydrogen at a faster rate than SMR, but it

produces less hydrogen from the same quantity of feedstock. The overall

efficiency of this process (50%) is less than that of SMR (65%-75%) and pure

oxygen is required. Two commercial technologies for this conversion are

available (i) Texaco Gasification Process, and (ii) Shell Gasification Process.

As a result of increasing natural gas prices, further development of natural

gas partial oxidation technology has been slowed down. The use of a solid

fuel like coal is also possible, through gasification, to produce a synthetic gas

(syngas) that can then be used in a partial oxidation process to obtain

hydrogen as product.

2.3.4 Like gasification of coal, biomass may also be gasified using a variety

of methods, primarily indirect and direct gasification. Indirect gasification uses

a medium such as sand to transfer heat from the char combustor to the

gasification vessel. In direct gasification heat is supplied to the gasification

vessel by the combustion of a portion of the feed biomass. In general,

hydrogen produced via direct gasification is expected to cost slightly more

(i.e., 5%) than that from the indirect mode.

2.3.5 In Biomass pyrolysis, biomass may be thermally decomposed at a

high temperature (in the range of 600-10000C) in an inert atmosphere to form

a bio-oil composed of about 85% oxygenated organics and remaining water.

The bio-oil is then steam reformed using conventional technology to produce

hydrogen. Alternatively, the phenolic components of the bio-oil can be

extracted with ethyl acetate to produce an adhesive/phenolic resin as a co-

product; the remaining components can be reformed as in the first option. The

product gas from both alternatives is purified using a standard pressure swing

adsorption (PSA) system.

2.3.6 The Kvaerner-process or Kvaerner carbon black & hydrogen process

(CB&H) is a method, developed in the 1980s by a Norwegian company for the

production of hydrogen from hydrocarbons (CnHm), such as methane, natural

gas and biogas. Of the available energy of the feed, approximately 48% is

contained in the hydrogen, 40% is contained in activated carbon and 10% in

the superheated steam.

30

2.4 Electrolysis of Water

The Electrolysis of water uses electrical energy to split water molecules

into hydrogen and oxygen. Large-scale electrolysis of brine (saltwater) has

been commercialised for chemical applications. Some small-scale electrolysis

systems also supply hydrogen for high-purity chemical applications, although

for most medium- and small-scale applications of hydrogen fuels, electrolysis

is cost-prohibitive. For renewable technologies, the capital costs dominate.

The cost of the electricity is a major concern because it is three to five times

more expensive as “feedstock” than fossil fuels. In fact, the high cost of the

electricity is the driving force behind the development of high-temperature

steam electrolysis. In this process, some of the energy driving the process

can be supplied in the form of steam instead of electricity. For example, at

1000°C, more than 40% of the energy required could be supplied as heat.

Current best process to have an efficiency of 50 - 80% and 1 kg of

hydrogen with specific energy of 143 MJ/kg (about 40 kWh/kg) requires 50 -

79 kWh electricity. At the cost of electricity as $0.08/kWh, hydrogen from

electrolysis would cost $4.00/kg hydrogen, which is 3 to 10 times the price of

hydrogen obtained from steam reforming of natural gas. The price difference

is due to the efficiency of direct conversion of fossil fuels to produce

hydrogen, rather than burning fuel to produce electricity. Hydrogen from

natural gas, used to replace e.g. gasoline, emits more CO2 than the gasoline it

would replace, and so is of no help in reducing greenhouse gases.

2.4.1 High Pressure Electrolysis

High pressure electrolysis is the electrolysis of water by decomposition

of water (H2O) into oxygen (O2) and hydrogen gas (H2) by means of an

electric current being passed through the water. This differs with the standard

electrolyser in terms of the hydrogen output at around 120-200 bar (1740-

2900 psi). By pressurizing the hydrogen in the electrolyser the need for an

external hydrogen compressor is eliminated, the average energy consumption

for internal compression is around 3%.

2.4.2 High Temperature Electrolysis

Hydrogen can be generated from energy supplied in the form of heat

(950–1000 °C) and electricity through High Temperature Electrolysis (HTE).

The electricity and heat generated through a nuclear reactor could be used for

splitting hydrogen from water. Research into high-temperature nuclear

reactors may eventually lead to a hydrogen supply that is cost-competitive

with natural gas-steam reforming. General Atomics predicts that hydrogen

produced in a High Temperature Gas Cooled Reactor (HTGR) would cost

31

$1.53/kg. In 2003, steam reforming of natural gas yielded hydrogen at

$1.40/kg. HTE has been demonstrated for hydrogen production at laboratory

scale (with a product having calorific value of 108 MJ (thermal) per kg) but not

at a commercial scale. This is lower-quality "commercial" grade Hydrogen,

which is unsuitable to use in fuel cells.

2.5 Photo-electrochemical Water Splitting

Using electricity produced by photovoltaic systems offers the cleanest

way to produce hydrogen. Water is broken into hydrogen and oxygen by

electrolysis—a photo-electrochemical cell (PEC) process which is also named

artificial photosynthesis. Research aimed toward developing higher-efficiency

multi-junction cell technology is underway by the photovoltaic industry. If this

process is assisted by photo-catalysts suspended directly in water instead of

using photovoltaic and an electrolytic system, the reaction is in just one step,

which can improve efficiency.

2.6 In photo-electro-catalytic production, a gold electrode is covered in

layers of indium phosphide (InP) nanoparticles and an iron-sulphur complex is

introduced into the layered arrangement, which when submerged in water and

irradiated with light under small electric current, produces hydrogen with an

efficiency of about 60%. The electricity production itself involves large

transformation losses, however, the efficiency of hydrogen production through

electrolysis relative to the primary energy content of the fuel input to

generation would be significantly lower. In certain cases, it may be

economical to use off-peak electricity, if it is priced well below the average

electricity price for the day; however, such market applications would have to

be balanced with other potential electricity supplies, the cost versus benefits

of appropriate metering and rate design, and the implied reduction in

utilization of the electrolysis unit, as described above. The development of

such an application could also support other technologies, such as plug-in

hybrid electric vehicles.

2.7 Hydrogen through Thermal Splitting of Water:

2.7.1 Concentrated Solar Thermal Energy: Very high temperatures are

required to dissociate water into hydrogen and oxygen. A catalyst is required

to make the process operate at feasible temperatures. Heating the water can

be achieved through the use of concentrating solar power. Hydrosol-II is a

100-kilowatt pilot plant in Spain, which uses sunlight to obtain the required

800 - 1,2000C to heat water. It has been in operation since 2008. The design

of this pilot plant is based on a modular concept. As a result, it may be

possible that this technology could be readily scaled up to the megawatt

32

range by multiplying the available reactor units and by connecting the plant to

heliostat fields (fields of sun-tracking mirrors) of a suitable size.

2.7.2 A promising long-term technology is the use of concentrated solar

energy for hydrogen production via electrolysis. Two primary process

configurations are used with this method. In the first, ambient temperature

electrolysis, concentrated solar energy is used to generate alternating current

(AC) electricity, which is supplied to the electrolyser. The second is the high-

temperature electrolysis of steam. In this system, the concentrator supplies

both heat and AC electricity to convert steam (1273 K) to hydrogen and

oxygen. In this system, an SOFC system would be operated in a reverse

mode to generate hydrogen instead of electricity. This technology is in an

early stage of development.

2.8 There are more than 356 thermo-chemical cycles for the production of

hydrogen by splitting water (without using electricity) though only around a

dozen of these cycles such as the iron oxide cycle, cerium(IV) oxide-

cerium(III) oxide cycle, zinc-zinc-oxide cycle, sulphur-iodine cycle, copper-

chlorine cycle and hybrid sulphur cycle are under research and in testing

phase. These processes can be more efficient than high-temperature

electrolysis, typical in the range from 35 - 49% (lower heating value)

efficiency. Thermo-chemical production of hydrogen using chemical energy

from coal or natural gas is generally not considered, because the direct

chemical path is more efficient. None of the thermo-chemical hydrogen

production processes have been demonstrated at production levels, although

several have been demonstrated in laboratories.

2.9 Biological Hydrogen Production

It is the fermentative conversion of organic substrate to bio-hydrogen

manifested by a diverse group bacteria using multi enzyme systems involving

three steps similar to anaerobic conversion. Two different fermentation routes-

dark fermentation and photo-fermentation routes are available. Dark

fermentation reactions do not require light energy, so they are capable of

constantly producing hydrogen from organic compounds throughout the day

and night. Photo-fermentation differs from dark fermentation because it only

proceeds in the presence of light. Biological hydrogen can be produced in an

algae bioreactor. In the late 1990s it was discovered that if the algae is

deprived of sulphur, it will switch from the production of oxygen, i.e. normal

photosynthesis, to the production of hydrogen.

Biological hydrogen can also be produced in bioreactors that use feed-

stocks other than algae, the most common feedstock being waste streams.

The process involves bacteria feeding on hydrocarbons and excreting

33

hydrogen and CO2. The CO2 can be sequestered successfully by several

methods, leaving hydrogen gas. A prototype hydrogen bioreactor using waste

as a feedstock is in operation at Welch's grape juice factory in North East,

Pennsylvania.

2.10 Bio-catalyzed Electrolysis

The electrolysis using microbes provides another possibility of

producing hydrogen besides regular electrolysis of water, with bio-catalyzed

electrolysis, hydrogen is generated after running through the microbial fuel

cell and a variety of aquatic plants can be used. These include reed sweet-

grass, cord-grass, rice, tomatoes, lupines, algae.

34

35

HYDROGEN PRODUCTION USING

THERMOCHEMICAL ROUTE FROM

CARBONACEOUS FEED-STOCKS

36

37

3.1 Hydrogen Production from Carbonaceous Sources

3.1.1 Introduction:

Hydrogen has been projected as one of the few long-term sustainable

clean energy carriers, emitting only water vapour as a by-product during the

combustion or oxidation process. Approximately 95% of the hydrogen

produced presently comes from carbonaceous raw materials derived primarily

from a fossilized carbonaceous feed-stock. Only a fraction of this hydrogen is

currently used for energy purposes; the bulk serves as a chemical feedstock

for fertilizer, petrochemical, food, electronics and metallurgical processing

industries. Hydrogen share in the energy market is increasing with the

implementation of fuel cell systems and the growing demand for zero-

emission fuels. Hydrogen production will need to keep pace with this growing

market.

The use of hydrogen for petrochemicals, fertilizers and as clean and

renewable energy carrier will increase substantially in the coming years as

even more stringent environmental legislations are enforced. Low sulfur

gasoline and diesel fuels will become mandatory and harmful emissions will

have to be reduced drastically. Hydrogen will be required by refiners and

specialty chemical manufacturers to meet the global need for cleaner

products. The growing fuel cell market will be dependent on hydrogen as a

primary fuel source. The Hydrogen Posture Plan, published by Energy

Efficiency and Renewable Energy (EERE), USA in February 2004, envisaged

a complete transition to a hydrogen economy by 2030–2040.

However, hydrogen is not readily available in sufficient quantities and

the production cost is still high for transportation purpose. The technical

challenges to achieve a stable hydrogen economy include improving process

efficiencies, lowering the cost of production and harnessing renewable

sources for hydrogen production.

3.1.2 International Status & Commercialisation

Conventional technologies for hydrogen production are:

a) Steam Methane Reforming

b) Partial Oxidation

c) Auto-Thermal Reforming

d) Methanol Reforming

e) Ammonia Cracking

f) Thermo-catalytic Cracking of Methane

g) Novel Reformer Technologies

38

A. Steam Methane Reforming

1. Process Description

Catalytic steam reforming of methane is a well-known, commercially

available process for hydrogen production. Hydrogen production is

accomplished in several steps: steam reforming, water gas shift reaction, and

hydrogen purification.

CH4 + H2O ↔ CO + 3 H2 ∆H= +206.16 kJ/mol CH4

The steam reforming reaction is endothermic and requires external

heat input. Economics favors reactor operation at pressures of 3 to 25

atmospheres and temperatures of 700 to 850°C. The external heat needed to

drive the reaction is often provided by the combustion of a fraction of the

incoming natural gas feedstock (up to 25%) or from burning waste gases,

such as purge gas from the hydrogen purification system. Heat transfer to the

reactants is accomplished indirectly through a heat exchanger. Methane and

steam react in catalyst filled tubes. Typically, the mass ratio of steam to

carbon is about 3 or more to avoid "coking" or carbon build-up on the

catalysts.

After reforming, the resulting syngas is sent to one or more shift

reactors, where the hydrogen output is increased via the water-gas shift

reaction which "converts" CO to H2.

CO + H2O ↔ CO2 + H2 ∆H = - 41.15 kJ/mol CO

This reaction is favored at temperatures of less than about 600°C, and

can take place at as low as 200°C, with sufficiently active catalysts. The gas

exiting the shift reactor contains mostly H2 (70-80%) plus CO2, CH4, H2O and

small quantities of CO. For hydrogen production, the shift reaction is often

accomplished in two stages. A high temperature shift reactor operating at

about 350-475°C accomplishes much of the conversion, followed by a lower

temperature (200-250°C) shift reactor, which brings the CO concentration

down to a few percent by volume or less. Hydrogen is then purified. The

degree of purification depends on the application. For industrial hydrogen,

pressure swing absorption (PSA) systems or palladium membranes are used

to produce hydrogen at up to 99.999% purity.

39

2. Status of Various Types of Steam Methane Reformers

a) Conventional Steam Methane Reformers

Steam methane reformers have been built over a wide range of sizes.

For large-scale chemical processes such as oil refining, steam reformers

produce 25 to 100 million standard cubic feet of hydrogen per day (1 scf =

0.02832 m3 or 28.32 L). These systems consist of long (12 meter) catalyst

filled tubes, and operate at temperatures of 850oC and pressures of 15-25

atm, which necessitates the use of expensive alloy steels. Capital costs for a

20 million scf H2/day steam reformer plant (including the reformer, shift reactor

and PSA) are about $200/kW H2 output; for a 200 million scf/day plant capital

costs are estimated to be about $80/kW H2.Refinery-type (high pressure, high

temperature) long tube reformers can be scaled down to as small as 0.1-1.0

million scf/day (the scale needed for producing hydrogen at refueling

stations), but scale economies in the capital cost are significant. The capital

cost is about $750/kW H2 at 1 million scf/day and $4000/kW H2 at 0.1 million

scf/day. Small-scale conventional (long tube, high temperature) steam

methane reformers are commercially available from a number of companies,

which normally produce large steam methane reformers for chemical and oil

industries. The main design constraints for these systems are high

throughput, high reliability and high purity (depending on the application).

The disadvantages of conventional long tube steam reformers for

hydrogen refueling station applications are their large size (12-meter long

catalyst-filled tubes are commonly used), and high cost (which is due to costly

materials requirements for high temperature, high pressure operation, and to

engineering/installation costs for these one of kind units). For these reasons, it

is generally believed in the hydrogen and fuel cell R&D communities that a

more compact, lower cost reformer will be needed for stand-alone hydrogen

production at refueling stations.

b) Compact “Fuel Cell Type” Steam Methane Reformers with

Concentric Annular Catalyst Beds

At small sizes, a more cost effective approach is to use a lower

pressure and temperature reformer, with lower cost materials. Steam

methane reformers in the range of 2000 to 120,000 scf H2/day have been

developed for use with fuel cells, and have recently been adapted for stand-

alone hydrogen production. In these systems, the heat transfer path is

properly engineered to make the device more compact, and the reformer

operates at a lower pressure and temperature (3 atm, 700°C), which relaxes

materials requirements. Estimates of mass produced costs for small .fuel cell

type. steam methane reformers indicates that the capital cost for hydrogen

40

production plants in the 0.1 to 1.0 million scf/day range would be $150-

$180/kW H2 assuming that 1000 units were produced.

The capital costs per unit of hydrogen production ($/kW H2) are similar

for fuel cell type small reformers and conventional, one-of-a-kind large

reformers, assuming that many small units are built. Energy conversion

efficiencies of 70%-80% are possible for these units.

c) Plate-type Steam Methane Reformers

Another innovation in the design of steam methane reformers for fuel

cell systems is the plate-type reformer. Plate-type reformers are more

compact than conventional reformers with long, catalyst-filled tubes or

annular-type reformers with catalyst beds. The reformer plates are arranged

in a stack. One side of each plate is coated with a steam reforming catalyst

and supplied with reactants (methane and steam). On the other side of the

plate, anode exhaust gas from the fuel cell undergoes catalytic combustion,

providing heat to drive the endothermic steam reforming reaction. The

potential advantages of a plate reformer are more compact, standardized

design (and lower cost), better heat transfer (and therefore better conversion

efficiency), and faster start-up (because each plate has a lower thermal inertia

than a packed catalyst bed).

The various reactors in the steam methane reformer system (e.g.

desulfurizer, steam reformer, water gas shift reactor, and CO clean-up stage)

are made up of plates of a standard size, greatly reducing the capital cost.

Heat transfer and heat integration between reactors is facilitated.

Plate-type steam methane reformers have not yet been

commercialised for fuel cell systems, but may allow for future capital cost

reduction by simplifying system design.

d) Membrane Reactors for Steam Reforming

Another promising technology is the .membrane reactor, where the

steam reforming, water gas shift and hydrogen purification steps all take place

in a single reactor. Methane and steam are fed into a catalyst-filled reactor

under pressure. On one side of the reactor is a high selectivity palladium

membrane that is selectively permeable to hydrogen. As the steam reforming

reaction proceeds, the hydrogen is driven across the membrane by the

pressure difference. Depending on the temperature, pressure and the reactor

length, methane can be completely converted, and very pure hydrogen is

produced, which is removed as the reaction proceeds. This allows operation

at lower temperature, and use of lower cost materials. A potential advantage

41

of this system is simplification of the process design and capital cost reduction

due to the need of fewer process vessels.

There is huge spurt in industrial R&D activity on membrane

technologies for syngas and hydrogen production. Interest by major energy

companies in applying membrane technology to large-scale syngas and

hydrogen production may have significant “spin-offs” for small-scale hydrogen

production as well. Recently patents have been issued on membrane reactor

reforming to a number of companies involved in fuel processor design for fuel

cells and on related ion transport membrane technology to oil companies,

Exxon, BP Amoco, Indiana, Standard Oil, USA and other industrial gas

companies like Air Products and Praxair. Recently Praxair and Argonne

National Laboratory launched a programme to develop a compact, low-cost

hydrogen generator based on ceramic membrane technologies. Steam,

natural gas and oxygen are combined in a catalyzed auto-thermal reforming

reaction. Oxygen is derived from air, using an oxygen transport ceramic

membrane (OTM) that operates at about 800-1000oC. High purity hydrogen is

removed using a high selective hydrogen transport membrane, also operating

at 800-1000oC. The OTM has been developed by Praxair and others in the

Oxygen Transport Membrane Syngas Alliance (BP, London, Amoco,Indiana

Statoil, Norway, Sasol, Johannesburg), South Africa, since 1997, and is now

undergoing Phase II pilot demonstration. The hydrogen transport membrane

is being developed at Argonne National Laboratory, and is in an early stage of

development.

In Japan, the Tokyo Gas company has built and tested a small

membrane reactor for production of pure hydrogen from natural gas at a rate

of 15 Nm3/h (about 12,000 scf/d), as well as steam reforming and partial

oxidation systems. Aspen Systems has demonstrated a membrane reactor for

steam reforming methane, ethanol and gasoline.

B. Partial Oxidation

1. Process Description

Another commercially available method for deriving hydrogen from

hydrocarbons is partial oxidation (POX). Here, methane (or some other

hydrocarbon feedstock such as oil) is oxidized to produce carbon monoxide

and hydrogen according to

CH4 + 1/2 O2→ CO + 2 H2 ∆H = -36 MJ/kmol CH4

The reaction is exothermic and no indirect heat exchanger is needed.

Catalysts are not required because of the high temperature. However, the

42

hydrogen yield per mole of methane input (and the system efficiency) can be

significantly enhanced by use of catalysts. A hydrogen plant based on partial

oxidation includes a partial oxidation reactor, followed by a shift reactor and

hydrogen purification equipment. Large-scale partial oxidation systems have

been used commercially to produce hydrogen from hydrocarbons such as

residual oil, for applications in refineries, etc. Large systems generally

incorporate an oxygen plant, because operation with pure oxygen, rather than

air, reduces the size and cost of the reactors.

Small-scale partial oxidation systems have recently become

commercially available, but intensive R&D activities are still underway. Small-

scale partial oxidation systems have a fast response time, making them

attractive for following rapidly varying loads, and can handle a variety of fuels,

including methane, ethanol, methanol, and gasoline.

The POX reactor is more compact than a steam reformer, in which heat

must be added indirectly via a heat exchanger. The efficiency of the partial

oxidation unit is relatively high (70-80%). However, partial oxidation systems

are typically less energy efficient than steam reforming because of the higher

temperatures involved (which exacerbates heat losses) and the problem of

heat recovery. (In a steam methane reforming plant, heat can be recovered

from the flue gas to raise steam for the reaction, and the PSA purge gas can

be used as a reformer burner fuel to help provide heat for the endothermic

steam reforming reaction. In a POX reactor, in which the reaction is

exothermic, the energy in the PSA purge gas cannot be fully recovered).

Because they are more compact, and do not require indirect heat

exchange (as in steam reforming), it has been suggested that partial oxidation

systems could cost less than steam reformers. Although the partial oxidation

reactor is likely to be less expensive than a steam reformer vessel, the

downstream shift and purification stages are likely to be more expensive.

Developing low cost purification technologies is the key, if POX systems are to

be used for stationary hydrogen production. Another approach is using pure

oxygen feed to the POX, which incurs high capital costs for small-scale

oxygen production, but eliminates the need to deal with nitrogen downstream.

Oxygen enrichment of incoming air is another way of reducing, but not

eliminating, the amount of nitrogen. Innovative membrane technologies such

as the Ion Transport Membrane (ITM) may allow lower cost oxygen for POX

reactors. This is being investigated by Air Products in its research related to

ITMs, and by Praxair and partners in its oxygen transport membrane

programme.

43

2. Status of Partial Oxidation Systems

A number of companies are involved in developing small-scale POx

systems. Small POx systems have been developed, for use with fuel cell

systems, by Arthur D. Little and its spin-off companies Epyx and Nuvera. Epyx

is supplying the onboard gasoline reformer for the USDOE’s gasoline fuel cell

vehicle project. Epyx recently formed a joint company with DeNora called

Nuvera, to commercialise POX reformer/PEM fuel cell systems. Nuvera has

reportedly shipped gasoline reformers to automotive companies for testing.

Hydrogen Burner Technology (HBT), Inc., California, USA has

developed a range of hydrogen production systems based on POx. This

includes a reformer that produces very pure H2 for cogeneration in buildings.

HBT, with funding from the California Air Resources Board, is installing a

natural gas reformer filling station for Sunline Transit at Thousand Palms, CA,

to supply hydrogen to fuel cell buses and Hythane® buses. HBT has a joint

venture with Gaz de France to distribute HBT’s products in Europe. Phoenix

Gas Systems (a HBT sub group) develops systems for industrial hydrogen

gas generation.

Argonne National Laboratory, Lemont, Illinois, USA has developed a

POx reformer suitable for use in vehicles. The USDOE is supporting work on

POx systems for onboard fuel processors for fuel cell vehicles through the

Office of Transportation Technologies Fuel Cell Program. Several companies

are involved in developing multi-fuel fuel processors for 50 kW fuel cell vehicle

power plants. These include:

As part of the Arthur D. Little/ Epyx/ Nuvera partnership, a gasoline fuel

processor built by Epyx was demonstrated with a PEM fuel cell. Plug

Power, Latham, New York is building an integrated 50 kW

gasoline/PEMFC system, based on the Epyx reformer.

McDermott Technology Inc., Alliance, Ohio, USA and Catalytica

Energy Systems Inc., Arizona are developing a multi-fuel fuel

processor for a 50 kW fuel cell.

Hydrogen Burner Technologies, Inc. is developing a multi-fuel

processor for a 50 kW fuel cell.

In addition, a number of automotive companies are in joint ventures to

develop gasoline fuel processors based on POX technology. These include:

General Motors. USA has joined with Exxon Mobil, USA to develop an

onboard gasoline fuel processor.

44

International Fuel Cells, South Windsor, USA has partnered with Shell

Hydrogen, Torrance, USA to develop and market a variety of fuel

processors.

Projects to use POx systems in stationary fuel cells include:

Tokyo Gas Company, Japan, has demonstrated a POx system for 1

kW fuel cell cogeneration system.

McDermott Technology, Inc. (MTI), USA and Catalytica Energy

Systems Inc., Tempe, Arizona, United States are working together to

develop compact fuel processors for use with PEMFCs and solid oxide

fuel cells (SOFCs). This system is designed to reform gasoline and

Naval Distillate for PEMFCs.

C. Autothermal Reforming

1. Process Description

Autothermal reformers (ATRs) combine some of the best features of

SMR and POx systems. Several companies are developing small ATRs for

converting liquid hydrocarbon fuels to hydrogen for use in fuel cell systems. In

autothermal reforming, a hydrocarbon feed (methane or a liquid fuel) is

reacted with both steam and air to produce a hydrogen-rich gas. Both the

SMR and POx reactions take place. For example, with methane

CH4 + H2O ↔ CO + 3 H2 ∆H = +206.16 kJ/mol CH4

CH4 + ½ O2→ CO + 2 H2 ∆H = -36 MJ/kmol CH4

With the right mixture of input fuel, air and steam, the POx reaction

supplies all the heat needed to drive the catalytic steam reforming reaction.

Unlike the SMR, the ATR requires no external heat source and no indirect

heat exchangers. This makes ATRs simpler and more compact than SMRs,

and it is likely that ATRs will have a lower capital cost. In an ATR all the heat

generated by the POx reaction is fully utilized to drive the steam reforming

reaction. Thus, ATRs typically offer higher system efficiency than POx

systems, where excess heat is not easily recovered. As with a SMR or POx

system, water gas shift reactors and a hydrogen purification stage are

needed.

2. Status of Autothermal Reformers

ATRs are being developed by a number of groups, mostly for fuel

processors of gasoline, diesel and logistics fuels and for natural gas fueled

45

PEMFC cogeneration systems. These include:

Argonne National Laboratory is testing ATR systems and catalysts

International Fuel Cells (IFC), South Windsor, USA designed an

ATR that runs on logistics fuels. BWX Technologies, Inc.,

Lynchburg, Virginia, and McDermott Technology, Inc. Using the IFC

ATR, a system was designed to reform Naval distillate for shipboard

fuel cells

Fraunhofer Institute for Solar Energy Systems, Freiburg, Germany

is designing ATRs for LPG and diesel fuel.

Degussa Metals Catalyst, Cardec Ag, Hanau, Germany is

developing catalysts for ATRs used with gasoline

Johnson-Matthey, Hamilton Bermuda developed a .Hot-Spot.

autothermal reformer, capable of reforming methanol and methane

Honeywell and Energy Partners, USA are developing a 50 kW

PEMFC system for buildings cogeneration. Both SMR and ATR are

being tried.

Daimler-Chrysler, USA is developing an ATR for gasoline reforming

McDermott Technology, Inc. (MTI), USA and Catalytica Energy

Systems Inc.,Tempe, Arizona, United States are developing a

small autothermal reformer for use with diesel and logistics fuels

on ships, based on an IFC design. A regenerable desulfurization

stage is important for Navy diesel fuel with 1% sulfur. Partners in

this activity are McDermott Technology, Inc. and Catalytica

Advanced Technologies, California, USA Ballard, Burnaby,

Canada,BWX Technologies, Lynchburg, Virginia, USA and Gibbs

& Cox, Arlington, Virginia, USA

The Idaho National Energy. USA and Environment Laboratory

(INEEL), USA with MTI and Pacific Gas and Electric, USA have

recently begun work on developing a 10 kW ATR system for

hydrogen refueling station applications.

Analytic Power, Canada has assessed multi-fuel reformer

technology, including ATR.

IdaTech, Bend, Oregon, United States has developed a multi-fuel

reformer, which produces very pure hydrogen from methane. It is

likely that the reformer is either a POX or ATR type.

Recently, Hydrogen Burner Technologies, Inc., Long Beach,

California, US began development of an autothermal reforming

system for use with fuel cells and for hydrogen production.

46

D. Methanol Steam Reforming

1. Process Description

Methanol is a liquid fuel that can be more easily stored and transported

than hydrogen. Because it can be readily steam reformed at moderate

temperatures (250-350oC), methanol has been proposed as a fuel for fuel cell

vehicles. Experimental fuel cell vehicles with onboard methanol reformers

have been demonstrated by Daimler-Chrysler, USA and Toyota and Nissan,

Japan. Although methanol steam reforming technologies are being developed

for fuel processors onboard fuel cell vehicles, it has also been suggested that

hydrogen might be produced by steam reforming of methanol at refueling

stations (Ledjeff-Hey et al. 1998).

The reactions for production of hydrogen via methanol steam reforming

are as follows:

CH3OH ↔ CO + 2 H2, ∆H = 90.1 kJ/mol; Methanol reforming

CO + H2O ↔ CO2 + H2 ∆H=-41.2 kJ/mol; Water gas shift reaction

or combining these:

CH3OH + H2O ↔ CO2 + 3H2

The reaction takes place in the presence of copper/zinc catalysts in the

temperature range 200- 350°C. Overall the reaction is endothermic, requiring

the application of heat, through an indirect heat exchanger, to a catalyst filled

tube or catalyst plate. Good thermodynamic conversion has been reported for

steam-to-carbon ratios of 1.5 and temperatures of 250-350°C. Various types

of methanol steam reformers have been designed. Earlier designs use

catalyst filled tubes that are indirectly heated via combustion of some of the

incoming methanol fuel. More recently, there has been an effort to develop

plate type reformers for methanol reforming. These have a number of

potential advantages including compactness, better heat transfer, faster start-

up and potentially lower cost. Membrane reactors have also been built for

steam reforming methanol.

For refueling station applications, a hydrogen purification stage, either

pressure swing adsorption unit or a membrane separation type, unit may be

required. The cost of the hydrogen production system might be lower for a

methanol steam reformer because it would operate at much lower

temperatures than a steam methane reformer. The cost of hydrogen produced

from methanol would be higher than hydrogen from small-scale steam

methane reforming, because methanol is a more expensive feedstock than

47

natural gas.

2. Status of Methanol Steam Reformers

Researchers at Los Alamos National Laboratory, USA have conducted

research on methanol steam reforming for PEM fuel cells. Researchers

at Argonne National Laboratory, USA have also simulated and built

methanol steam reformers.

Several automakers demonstrating fuel cell vehicles have developed

onboard steam reformers for methanol. These include Excellis Fuel

Cell Engines (DaimlerChrysler) of USA, and Toyota and Nissan of

Japan.

The European Commission funded two projects to develop onboard

fuel processors for fuel cell vehicles as part of the JOULE II project.

The MERCATOX project had the goal of producing a prototype

integrated methanol reformer and selective oxidation system.

Wellman CJB Ltd., a British company that has produced units for

steam reforming of alcohols, hydrocarbons, ethers and military fuels,

coordinated the MERCATOX project. The reformer consists of a series of

catalytic plates, with combustion of anode off-gas on one side and reforming

on the other side. Loughborough University designed the gas clean-up

system. Wellmann built and tested a plate type steam methanol reformer and

integrated the system, Rover Cars Company addressed manufacturing and

vehicle design issues, and Instituto Superior Technico undertook modeling

work

Northwest Power Systems (now called IdaTech), Thief River Falls,

Minnesota, United States has developed a multi-fuel processor. They

have demonstrated pure hydrogen production via steam reforming of

methanol, using a palladium membrane for the final purification step

Researchers at InnovaTek, Inc., Richland, Washington, USA have

demonstrated microreactor technology to create a portable hydrogen

source for fuel cells by reforming methanol

Researchers at Mitsubishi Electric Corporation, Japan are developing a

compact, plate-type steam methanol reformer

Researchers at the Royal Military College, Ontario, Canada, are

studying the effects of catalyst properties on methanol reforming

Researchers at Honeywell, USA are developing a compact plate-type

steam methanol reformer for automotive applications

Researchers at NTT Telecommunications Laboratory, and Tokyo

University are developing a compact plate-type steam methanol

reformer for automotive applications

48

Researchers at Gerhard-Mercator-Universitat, FRG, are developing

compact membrane reactors for methanol steam reforming

E. Ammonia Cracking

Ammonia is widely distributed to consumers today, is low cost and is

relatively easy to transport and store, compared to hydrogen. These attributes

make it a potential candidate for use as a hydrogen carrier for fuel cell

applications.

Ammonia can be dissociated (or cracked) into nitrogen and hydrogen

via the reaction:

2 NH3 -> N2 + 3 H2

The reaction is endothermic, and ammonia cracking takes place in indirectly

heated catalyst filled tubes. The dissociation rate depends on the

temperature, pressure and catalyst type. The reaction rate is increased by

operating at temperatures of 700oC or above, although dissociation can occur

at temperatures as low as 350oC. The main impurities are traces of un-

reacted ammonia and nitrogen oxides. The concentration of un-reacted

ammonia must be reduced to the ppm level for use in PEM fuel cells, although

alkaline fuel cells are not as sensitive to this. For PEMFC applications, where

low levels of ammonia impurity are required, a recent study recommends

reaction temperatures of 900oC .The overall efficiency of fuel processor

systems based on ammonia cracking has been reported to be up to 85%.

Maximum values of about 60% were reported in another recent study, by

Analytic Power, for small ammonia crackers for PEM fuel cell applications,

where up to 40% of the product hydrogen was combusted to supply heat to

drive the dissociation reaction and to compensate for heat losses.

A potential advantage of ammonia cracking for hydrogen generation in

a fuel cell system is simplicity of reactor. Unlike a steam reformer system,

water is not required as a co-feed with the fuel, and no water gas shift

reactors are needed. When an ammonia cracker is closely coupled to a fuel

cell, no final hydrogen purification stage is needed. Because nitrogen is inert

and has no effect in the fuel cell, it is simply passes through as a diluent. For

pure hydrogen production based on ammonia cracking, however, a costly

separation of H2 and N2 would be required, for example by using a PSA unit

or a hydrogen selective membrane. The cost of pure hydrogen production

through ammonia cracking has not yet been estimated.

49

F. Thermo-catalytic Cracking of Methane

In this approach, methane is broken down into carbon and hydrogen in

the presence of a catalyst at high temperature (850-1200oC), according to the

reaction

CH4 → C + 2 H2 ∆H = 17.8 kcal/mole CH4

This reaction is endothermic, requiring energy input of about 10% of the

natural gas feedstock. Researchers at the Florida Solar Energy Center, USA

have studied thermocatalytic methane cracking. This technology is still far

from commercial application for hydrogen production. The primary issues are

low efficiency of conversion and coking (carbon fouling of the catalyst).

Catalytic cracking of other hydrocarbons has been investigated by

researchers at Gerhard- Mercator-Universitat at Duisburg, Germany. Frequent

regeneration of the catalyst is required to remove accumulated carbon, but

relatively low capital costs are projected because of the system’s simplicity.

G. Novel Reformer Technologies

1. Sorbent Enhanced Reforming

Recently several authors have investigated the possibility of sorbent

enhanced steam methane reforming. Here, an absorbent (such as calcium

oxide) is mixed with the steam reforming catalyst, removing the CO and CO2

as the steam reforming reaction progresses. The resulting syngas has a

substantially higher fraction of hydrogen than that produced in a catalytic

steam-reforming reactor. A syngas composition was recently reported of 90%

H2, 10%CH4, 0.5% CO2 and <50 ppm CO. This reduces the need for

downstream processing and purification, which can be expensive in a small-

scale steam reformer. Moreover, when CO2 is removed by the sorbent, the

reaction can take place at lower temperature (400-500oC vs. 800-1000oC) and

pressure, reducing heat losses and material costs. Sorbent-enhanced

systems are still at the demonstration stage, and show promise because of

their low cost. Issues requiring further research include catalyst and sorbent

lifetime and system design.

2. Ion Transport Membrane (ITM) Reforming

Air Products, in collaboration with the USDOE and other members of

the ITM syngas team (Cerametec, Chevron, Eltron Research, McDermott

Technology, Norsk Hydro, Pacific Northwest Laboratory, Pennsylvania State

University, University of Alaska, and University of Pennsylvania, all from

USA), are developing ceramic membrane technology for generation of H2 and

50

syngas. The membranes are non-porous, multi-component metallic oxides

that operate at high temperature (>700oC) and have high oxygen flux and

selectivity. These are known as ion transport membranes (ITM). Conceptual

designs were carried out for a hydrogen-refueling station dispensing 0.5

million scf/day of 5000 psi hydrogen, following work by Directed Technologies,

Inc. Initial estimates show the potential for a significant reduction in the cost of

high pressure H2 produced via this route at the 0.1 to 1.0 million scf/day size.

For example, compared to trucked-in liquid hydrogen, the ITM route offers a

27% cost savings. Oxygen can be separated from air fed to one side of the

membrane at ambient pressure or moderate pressure (1-5 psig) and reacted

on the other surface with methane and steam at higher pressure (100-500

psig) to form a mixture of H2 and CO. This can then be processed to make

hydrogen or liquid fuels. Various configurations for the ITM reactor were

examined, and a flat-plate system was chosen because it reduced the number

of ceramic-metal seals needed. An independent effort to develop oxygen

transport membranes is ongoing at Praxair in conjunction with the Oxygen

Transport Membrane Syngas Alliance.

3. Plasma Reformers

Thermal plasma technology can be used in the production of hydrogen

and hydrogen-rich gases from methane and a variety of liquid fuels. Thermal

plasma is characterized by temperatures of the order of 3000-10,000oC, and

can be used to accelerate the kinetics reforming reactions even without a

catalyst. The plasma is created by an electric arc. Reactant mixtures (for

example, methane plus steam or diesel fuel plus air and water) are introduced

into the reactor and H2 plus other hydrocarbon products are formed.

Researchers at MIT, USA (Bromberg et al. 1999) have developed plasma-

reforming systems. The plasma is created by an electric arc in a plasmatron.

One set of experiments involved partial oxidation of diesel fuel. Steam

reforming of methane was also investigated. The best steam reforming results

to date have shown 95% conversion of methane and specific energy use (for

electricity for the plasmatron) of 14 MJ/kg H2 (an amount equal to about 10%

of the higher heating value of hydrogen). It is projected that the power

required for the plasmatron can be reduced by about half. With the National

Renewable Energy Laboratory (NREL) and BOC Gases, MIT researchers are

evaluating the potential of this technology for small-scale hydrogen

production. Researchers at Idaho National Energy and Environment

Laboratory (INEEL), USA and DCH are also working on plasma reforming

(DOE Hydrogen R&D Program Annual Operating Plan, March 2000).

4. Micro-channel Reformer

Researchers at Pacific Northwest National Laboratory, USA have

51

developed a novel gasoline steam reformer with micro-channels. The aim of

this work is to reduce the size of automotive reformers.

Over the past ten years, the rapidly growing interest in fuel cell and

hydrogen technologies has led to a variety of efforts to develop low cost

small-scale fuel processors and hydrogen production systems. The trend has

been to develop more compact, simpler and, therefore, lower cost reformers.

From the conventional long tube refinery-type steam methane reformer, fuel

cell developers moved toward more compact heat exchange-type steam

reformers (which are now commercialised as fuel cell components and for

stand-alone hydrogen production). Plate type reformers are now undergoing

development and testing for fuel cell applications and may be the next step in

compactness and simpler design. In plate reformers, each plate has a double

function (on one side, the reforming reaction take place, on the other, catalytic

heating drives the reaction). POx systems and ATRs offer simpler first stages

than steam reformers, but involve more complex purification systems.

Advanced purification systems are being devised for these reformers. Sorbent

enhanced reforming is another approach that combines several steps in one

reactor, with the potential of capital cost reductions. An area of intense

interest in the fuel cell and hydrogen R&D communities is development of

membrane reactors for reforming. Membrane reactors offer further

simplification, because the reforming, water gas shift and purification step

take place in a single reactor. Very pure hydrogen is removed via hydrogen-

selective permeable membranes. Membrane reactor systems are being tested

at small scale.

In parallel with fuel cell developments, there has been a growing

interest in innovative technologies for syngas production among large

chemical and energy producing companies. For example, ion transport and

oxygen transport membranes are under development for syngas applications.

These are now being applied to hydrogen production as well. Application of

membrane technology to syngas and hydrogen systems is an active area of

research in the fuel cell R&D community and among large-scale producers of

syngas such as oil companies. In addition, oil companies such as BP Amoco,

U. K.; Shell, Houston, USA and Exxon/Mobil, Houston, Texas are involved in

joint ventures to develop fuel processors and hydrogen infrastructure

demonstrations, such as hydrogen refueling stations based on methane

reformers. The oil companies are positioning themselves to become suppliers

of hydrogen transportation fuel in the future.

3.1.3 National Status and Commercialisation Efforts by industry

The focus of RD&D in India has been on production of hydrogen from

renewable sources of energy.

52

(a) Status of Hydrogen Production Technologies in India

The Indian Institute of Chemical Technology (IICT), Hyderabad

designed and developed a methanol reformer to produce around 10,000

litres/hour hydrogen for coupling with 10 kW fuel cell. It was operated for 1000

hours and data was collected. Based on this data a scaled up methanol

reformer to produce around 50,000 litres/hour hydrogen was designed and

developed to demonstrate the technology by coupling with 50 kW fuel cell

system. The reformed gas contained around 75% hydrogen with pre-mixed

methanol and water. The product gas was further processed to lower down

CO2 and CO content to the extent less than 10 ppm, which is desirable for use

in PEMFC system for power generation.

IICT, Hyderabad also developed three catalysts viz, Ni/SiO2 (NS), Ni/

Alumina Sol [Ni/Al2O3] Ni/ Alumina Plural (NAP) [Ni/Al2O3] for reformation of

glycerol at 500-650ºC on bench scale for hydrogen production to generate

data of reaction kinetics to scale-up reformer. Based on this data a skid

mounted reactor was fabricated and installed at the institute. The life of these

catalyst lasted for several hours.

The Centre for Energy Research, SPIC Science Foundation, Chennai

(stopped R&D activities on hydrogen energy and fuel cells) designed,

developed and demonstrated a PEM methanol electrolyser for the production

of hydrogen at the rate of 1 Nm3/hour at an operating temp of 50-60oC. The

energy consumption was around 2.02 kWh/Nm3hydrogen produced. The

hydrogen gas obtained from this electrolyser contains considerable amount of

methanol, which can be removed bypassing it through water scrubber and

chiller. This hydrogen is almost free from CO2 and CO.

Central Institute of Mining and Fuel Research (CIMFR), Dhanbad

developed an ovel process for the production of hydrogen from renewable

and fossil fuel based liquid and gaseous hydrocarbons by non-thermal plasma

reformation technique. A non-thermal plasma reactor of 0.5 litre capacity was

developed for reformation of hydrocarbons to produce about 12 litres/minute

hydrogen enriched gas mixture. Conversion of methane to hydrogen has been

studied in a quartz reactor by non-thermal plasma. Experiments have been

conducted for non-thermal plasma reformation of soybean oil, methanol and

ethanol with both conventional cylindrical fuel reformer as well as vortex type

reformer. Appreciable hydrogen production was also achieved with naphtha.

Bio-diesel will also be tried for hydrogen production through this process.

The Indian Institute of Technology Hyderabad is working for the

transformation of greenhouse gases like methane and CO2 into for

53

syngas/H2bylow temperature plasma catalysis. This will be achieved by

optimizing conditions like reactor design, diluting gas, discharge gap,

residence time of the gas, screening of various catalysts, etc. for a hybrid non-

thermal plasma reactor. Heterogeneous catalysts will be searched /

synthesized to arrive at a robust and cost-effective catalytic non-thermal

plasma reactor for syngas production. Earlier IIT Hyderabad had worked on

developing a process for dissociation of hydrogen sulphide into hydrogen and

sulphur using non-thermal plasma process.

b) Gap Analysis & Way Forward

There are already extensive industry and government programmes

addressing particular technical issues for small-scale reformers, and for

syngas production. We have not attempted to list research priorities for each

type of reformer, or select a particular technical area for basic research.

Instead, we suggest that the National/International agencies develop

collaborative projects aimed at enhancing interactions between researchers

engaged in small-scale hydrogen production (fuel cell and hydrogen

researchers) and those engaged in large energy production (oil and chemical

companies). The purpose of the proposed projects would be to examine the

potential impact of recent technical progress for small- and large-scale

hydrogen energy production.

One project could be to identify areas where ongoing research on

large-scale syngas technologies could lead to development of small-

scale hydrogen production systems for vehicles, and vice versa. To

identify such areas, the MNRE could convene a group of industry and

academic researchers from fuel cell, hydrogen and energy producing

communities to discuss issues for small-scale reformers for hydrogen

production. This group might have particular interest in technologies

that could have applications in small- and large-scale hydrogen

production and could ultimately facilitate capture ofCO2 during

hydrogen fuel production. Membrane technology would appear to be a

good candidate for such an information exchange meeting, but other

areas might be identified. If gaps in technical knowledge were

identified, this could help focus future reformer development efforts.

54

3.2 Hydrogen Production through Biomass Gasification

3.2.1 Biomass is a renewable source of energy and can be considered as a

distributed source for hydrogen production. However, out of all different routes

of hydrogen production from biomass, gasification is likely to be the most

economical and sustainable process. The basic steps for getting pure

hydrogen out of biomass through gasification are similar to those for coal,

methane and naphtha reforming based processes.

3.2.2 International Status

Research & development work in the area of production of hydrogen

using biomass is being carried out at the international level by various

organisations. However, till date no commercial technology is available to

generate hydrogen from biomass. The reported hydrogen production is

mainly through fluidized bed gasification or conversion of pyrolytic oil. The

work done at various institutions/ organisations is summarised below:

The University of British Colombia, Canada, is working on fluidized bed

gasification and sorbent based hydrogen separation unit. The National

Renewable Energy Laboratory (NREL), U.S.A. has demonstrated production

of hydrogen from pyrolysis oil by steam reforming. This pyrolysis oil was

obtained from peanut shells in a fluidized bed by pyrolysis process. Some

studies were done on pyrolysis and gasification of rubber, poplar wood, yellow

pinewood and residual branches of oil palm tree as fuel in a thermally

controlled environment and steam was passed at the desired flow rate over a

fixed mass of biomass for gasification. The gasifier was operated in the

temperature ranges of 600-10000C and 800 - 9000C. Maximum yield of

hydrogen was obtained in the temperature range of 600-10000C. The

hydrogen yield was about 20 g per kg of biomass through pyrolysis and 97 g

per kg of biomass through steam gasification, with over 55% volume fraction

of hydrogen in the syngas. The influence of temperature on various

performance parameters was evaluated and analyzed. There were no

significant changes in syngas and hydrogen yield at various gasification

temperatures but the pyrolysis temperature had a considerable effect on the

overall yield. The syngas yield increased from 353 g per kg of biomass to 828

g per kg of biomass by varying the pyrolysis temperature from 600 to 10000C

with a reduction of over 50% in solid residue at the end of the process. The

reaction rates enhanced significantly with increase in temperature, 35 g of

substrate took 200 min for complete gasification at 6000C compared to 29 min

at 10000C for constant flow of steam at 3.1 g/s. The extremely slow rate of the

char-steam reaction is cited as the reason for the slow rate of gasification at

low temperatures. High temperature and long residence time were identified

55

as important parameters that favor higher H2 yields. Over 30% higher energy

yield was reported from gasification compared to pyrolysis due to significant

contribution of the char-steam reaction.

Gas Technology Institute (GTI), Chicago, has been working on

demonstration project for direct generation of hydrogen in a down draft

gasifier using a membrane reactor. The Energy Research Centre of the

Netherlands (ECN) has developed gasification technology, which has

progressed to a pilot plant scale (800 kWth).Currently ECN, with other partners

is planning to construct a 12 MWth synthetic natural gas (SNG) plant in

Alkmaar, the Netherlands. The gasifier has been designed with a tar

scrubbing unit. Methanation of the product gases is done after removing

sulphur, chloride and CO2. The Technical University of Vienna has developed

a fast internally circulating fluidized-bed technology for steam-blown

gasification of biomass in cooperation with Austrian Energy and Environment.

This technology is being employed in the Gothenburg Biomass Gasification

(GoBiGas), project, which aims at constructing a SNG plant in Gothenburg,

Sweden. At Gussing, Austria, an 8 MW combined heat and power plant is in

operation since 2002. Later on, SNG production was demonstrated in a

methanation unit, which took a 1 MW SNG slipstream from the Güssing plant.

There has been no reported work on fixed bed gasification. The targeted cost

of production of hydrogen was around US$ 2.6/kg.

3.2.3 Biomass Pyrolysis

Pyrolysis is the heating of biomass at a temperature of 600-10000C at

0.1–0.5 MPa in the absence of air to convert biomass into gaseous

compounds, liquid oils, and solid charcoal. Pyrolysis can be further classified

into slow and fast pyrolysis. As slow pyrolysis gives high char yield, it is

generally not considered for hydrogen production. Fast pyrolysis is a process

where biomass feedstock is heated rapidly (at 150-250oC/s) in the absence of

air, to form vapour and subsequently condense it to a dark brown bio-liquid.

The following products are obtained from the fast pyrolysis process:

(i) Gaseous products include H2, CH4, CO, CO2 and other Higher Hydro

Carbons (HHC) depending on the organic nature of the biomass.

(ii) Liquid products include tar and oils that remain in liquid form at room

temperature like acetone, acetic acid, etc.

(iii) Solid products are mainly composed of char and almost pure carbon

plus other inert materials.

Although most pyrolysis processes are designed for biofuels

production, hydrogen can be produced directly through fast or flash pyrolysis,

56

if high temperature and sufficient volatile phase residence time are allowed as

follows:

Biomass +heat →H2+ CO +CH4 + HHC + C (char) - - (i)

CO, methane and other hydrocarbons are reformed catalytically in

subsequent stages to get more hydrogen. Besides the gaseous products, the

oily products can also be processed for hydrogen production. The pyrolysis oil

can be separated into two fractions based on water solubility. The water-

soluble fraction is used for hydrogen production while the water-insoluble

fraction for adhesive formulation.

Studies have shown that when Ni-based catalyst is used, the maximum

yield of hydrogen can reach 90%. Bio-oil needs to be steam reformed at 750-

850 0C in presence of nickel based catalyst followed by shift reaction. With

additional steam reforming and water–gas shift reaction, the hydrogen yield

can be increased significantly. Temperature, heating rate, residence time and

type of catalyst used are important pyrolysis process control parameters. In

favor of gaseous products especially in hydrogen production, high

temperature, high heating rate and long volatile phase residence time are

required.

3.2.4 Biomass Gasification

Biomass gasification is sub-stoichiometric combustion process, in

which pyrolysis, oxidation and reduction take place. Pyrolysis products

(volatile matter) further reacts with char and are reduced to H2, CO, CO2, CH4

and HHC.

Biomass + heat + O2 → H2 +CO + CO2 + CH4 + HHC + char - (ii)

Unlike pyrolysis, gasification of solid biomass is carried out in the

presence of oxidiser. Besides, gasification aims to produce gaseous products,

while pyrolysis aims to produce bio-oils and charcoal. One of the major issues

in biomass gasification is to deal with the tar formation that occurs during the

process. The unwanted tar may cause the formation of tar aerosols through

polymerization to a more complex structure, which are not favorable for

hydrogen production through steam reforming. This tar formation may be

minimized by: i) designing gasifier properly, ii) with controlled operation (in

terms of temperature and residence time) of gasifier and iii) with

additives/catalysts.

57

Tar may be thermally cracked at temperature above 10000C. The two-

stage gasification and secondary air injection in the gasifier may also reduce

tar formation.

The use of some additives (dolomite, olivine and char) inside the

gasifier also helps in tar reduction. When dolomite is used, 100% elimination

of tar can be achieved. Catalysts not only reduce the tar content, but also

improve the gas product quality and conversion efficiency. Dolomite, Ni-based

catalysts and alkaline metal oxides are widely used as gasification catalysts.

H2 content in biomass is only around 6.5% (by wt.). But using steam as

the gasifying agent and air/O2 as the oxidizer, enhances the H2 output

considerably. One of the major advantages of the gasification is that the

process is carbon neutral and it has flexibility in using various types of

biomass including agricultural and municipal solid waste.

3.2.5 Thermo-chemical Conversion of Biomass: As a process for

hydrogen generation this route had never been a prime area of research, but

major emphasis was towards standardizing the gasification system for power

generation using reciprocating engines and for thermal applications. Biomass

gasification has been identified as a possible process for producing renewable

hydrogen. Most of the research has been stimulated by the techno-

economics, based on gasifier performance data acquired during proof of

concept testing.

In recent years, many researchers have explored the gasification of

biomass for hydrogen production using different reactor configurations. In a

fluidized bed reactor steam was introduced with oxygen and nitrogen under

temperature controlled conditions. The reactor was externally heated to

control the reactor temperature and the reactant flow rates were varied to

determine the effect of the equivalence ratio and the steam to biomass ratio

on the gas quality. H2 yield showed pronounced improvement with increasing

reactor temperature. Increasing the temperature from 800 to 9500C (at SBR =

1.8 and ER = 0.18) doubled the yield of H2 from 28 to 61 g per kg of biomass.

The effect of increased steam to biomass ratio (SBR) and equivalence ratio

(ER) on the hydrogen yield suggests that increasing the SBR (at an ER = 0)

from 1.1 to 4.7 increased the hydrogen yield from 46 to 83 g per kg of

biomass, whereas reducing the ER from 0.37 to 0 (at SBR = 1.7) enhanced

the H2 yield from 23 to 60 g per kg of biomass. The maximum H2 volume

fraction in syngas is reported as 57% at SBR of 4.7 and ER of 0, while

maintaining the bed temperature at 8000C The reported tar levels are in the

range of 6 g per kg of dry fuel, amounting to about 2500 ppm of tar and can

have serious implications on the downstream elements for hydrogen

separation.

58

Oxygen-steam gasification has been reported using pinewood

(CH1.6O0.6) with 8% moisture as fuel in a fixed bed downdraft gasifier. The 1.3

m high and 35 cm diameter downdraft gasifier was preheated up to 9000C by

igniting the feedstock and circulating the heat by a fan. Later, biomass was

placed over a bed of charcoal and oxygen was injected from multiple points.

Saturated steam at near ambient pressure was used. The oxy-steam

gasification was performed with ER varying between 0.22 and 0.26 and SBR

varying between 0.4 and 0.8 (molar basis). The maximum hydrogen yield

reported is 49 g per kg of dry biomass at ER of 0.25 and SBR of 0.8.A high tar

yield in the range of 3 to 20 g per kg of biomass was reported.

The effect of heating rate, temperature and SBR on H2 yield, tar

reduction and char residue was also studied in a co-current flow using a 1.8 m

long downdraft reactor of 20 mm diameter with legume straw and pine

sawdust as feed-stock. Steam was injected at 3000C, keeping the reactor at

the desired temperature using electrical heating coils. SBR (on mass basis)

was varied from 0 to 1 while working in a temperature range of 700 - 8500C.

Steam and biomass flow rates were simultaneously controlled for different

SBR values keeping residence time constant. At 8000C, using legume straw

as the substrate, H2 yield peaked at SBR (mass basis) 0.6 to 40.3% (volume

fraction), reporting significant reduction in tar from 66.6 g/Nm3 at SBR of 0 to

23.1 g/Nm3 at SBR of 0.6. Reduction in char residue is reported with increase

in SBR keeping temperature constant at 8000C, resulting in 5.5 % char

residue at SBR of 0 and 2.8 % at SBR of 0.6. Increase in syngas and H2 yield

with reduction in tar and char residue is reported with increase in temperature.

Keeping the SBR (mass basis) constant at 0.6, temperature was varied and

significant reduction in tar and char residue is reported. Tar content in syngas

got reduced from 62.8 g/Nm3 at 7500C to 3.7 g/Nm3 at 8500C while char

residue reduced from 7% to less than 2% in the same temperature range.

Dalian University of Technology, China inferred that addition of steam favored

tar and char reduction and subsequent increase in syngas and H2 yield due to

tar steam reforming, cracking and char gasification enhanced by higher

reaction rates at higher temperature.

Results from the previous work suggest the choice of gasification over

pyrolysis for higher hydrogen yield and efficiency. The literature has indeed

provided details on the various thermo-chemical conversion processes,

behavior of different reactor configurations and influence of various process

parameters like SBR, ER and temperature on hydrogen yield and overall

performance. It must be emphasized that the thermochemical conversion of

biomass to syngas, rich in hydrogen is one of the efficient processes. Steam

gasification of biomass has been studied in a batch reactor under the

controlled conditions but less exploited in a fixed bed reactor for continuous

59

hydrogen production. Further, the results from the literature indicate low

hydrogen yield and issues arising from the gas contaminated with higher

molecular weight compounds, i.e., the “tar”, inducing difficulty in separating

hydrogen from the syngas mixture.

Depending upon the type of fuels used, there are different kinds of

gasifier, differing in design. All these processes can be operated at ambient or

increased pressure and serve the purpose of thermo-chemical conversion of

solid biomass. Five major types of gasifiers are- fixed-bed updraft, fixed-bed

downdraft, fixed-bed cross-draft, bubbling fluidized bed, and circulating

fluidized bed gasifiers. This classification is based on the means of supporting

the biomass in the reactor vessel, the direction of flow of both the biomass

and oxidant, and the way heat is supplied to the reactor. Fixed bed gasifiers

are typically simpler, less expensive, and produce a lower heat content

producer gas. Fluidized bed gasifiers are complicated, expensive, and

produce a gas with a higher heating value. Table 3.1 compares the

advantages and limitations of different type of gasifier designs.

Table 3.1: Relative advantages and disadvantages of different types of

gasifier

Gasifier Advantages Disadvantages

Updraft

fixed bed

Mature for small-scale heat

applications

Can handle high moisture

No carbon in ash

Feed size limits

High tar yields

Scale limitations

Low heating value gas

Slag formation

Downdraft

fixed bed

Small-scale applications

Low particulates and low tar

Feed size limits

Scale limitations

Low heating value gas

Moisture-sensitive

Bubbling

fluid bed

Large-scale applications

Feed characteristics

Direct/indirect heating

Higher heating value gas

Medium tar yield

Higher particle loading

Circulating

fluid bed

Large-scale applications

Feed characteristics

Higher heating value gas

Medium tar yield

Higher particle loading

Entrained

flow fluid

Can be scaled up

Low tar formation

Low methane content gas

Higher heating value gas

Large amount of carrier

gas

Higher particle loading

particle size limits

60

The fixed bed gasifiers are broadly classified as updraft, downdraft and

cross draft depending on the direction of air flow. Downdraft type of gasifier, in

which the fuel and air move downwards, is widely used because it generates

combustible gas with low tar content. The reactor design used until recently

was the closed top, with the upper portion of the reactor acting as a storage

bin for the fuel. The air is allowed to enter at the lower part, which generally

contains charcoal. The developmental work at the Indian Institute of Science,

Bangalore (IISc) on wood gasifier has resulted in a design with an open top

with air entering both at the top and at the bottom through air nozzles. This

feature has resulted in a design which can handle wood chips of higher

moisture content up to 25%, and produce gas with low tar levels (< 30 ppm).

The low tar level is due to the stratification of the of the fuel bed helping in

maintaining a large bed volume at high temperature. In steady operation, the

heat from the combustion zone near the air nozzles is transferred by radiation,

conduction and convection upwards causing wood chips to pyrolyse and

loose 70-80% of its weight. These pyrolysed gases burn with air to form CO2

and H2O raising the temperature to 1000-11000C.The product gas from the

combustion zone further undergoes the reduction reactions with char, to

generate combustible products like CO, H2 and CH4.

3.2.6 Exergy and Energy Analysis

Apart from the demand and usefulness, energy efficiency is one of the

most important criteria to assess the performance and sustainability of any

technology. In the gasification process, the first law of thermodynamics

permits conservation of the total energy in the conversion of solid fuel to

gaseous fuel and the second law restricts the availability of energy (exergy)

transformed to useful form. In the case of gasification process, evolution of

gaseous species increases the entropy and introduces irreversibility in the

overall thermo-chemical conversion process. During the conversion of solid

fuel to gaseous fuel, apart from the process irreversibility, the transformation

of chemical energy in the solid fuel partly to thermal energy as sensible heat

cannot be converted to the desired output i.e., chemical enthalpy in the

gaseous species. Evaluating the energy efficiency based on the energy output

to the energy input and identifying the energy loss from the system to the

environment is appropriate while considering the device. This approach may

not be sufficient while evaluating the process and the device together as a

system. Identifying the internal losses arising due to the irreversibility is

important towards understanding any energy conversion process and

probably helps in redesigning the system elements. Exergy analysis thus

helps in evaluating the conversion process and provides an insight towards

optimizing, by minimizing the losses, if any.

61

The exergy efficiency of a fast pyrolysis bio-oil production plant was

analyzed using Aspen Plus software. Based on this analysis it was found that

the exergy efficiency is 71.2% and the components for the exergy losses were

also identified. The areas that had been identified for improvement were

biomass drier, milling process for size reduction and heat exchanger used for

pre-heating the combustion air.

In the area of biomass gasification, researchers have performed exergy

analysis based on equilibrium analysis using Engineering Equation Solver

(EES) software. With the focus on H2 production, from a gasifier reactor of

0.08 m diameter and 0.5 m height using sawdust as the fuel, exergy and

energy efficiencies were estimated. The heat loss from the reactor was

modeled assuming isothermal condition. Tar, generally an issue for

gasification process and its utilization, was considered as a useful product

(fuel) and modeled as benzene molecule in the system. Effects of varying the

SBR (steam to biomass ratio) from 0.2 to 0.6 were studied, by varying steam

flow rate from 4.5 kg/s to 6.3 kg/s and biomass feed rate from 10 kg/s to 32

kg/s was considered. In the analysis, temperature was varied between 700

and 12000C and its influence on the H2 yield, exergy and energy efficiency

was also studied. The maximum exergy efficiency reported is about 65% with

minimum near SBR of 0.4.It has been shown that maximum specific entropy

generation is between 0.37 and 0.42.The lower value of the exergy efficiency

has been argued due to the increase in internal irreversibility with the varying

SBR. H2 yield was saturated at around SBR of 0.7. It is evident that in the

temperature range of 700-12000C, char-steam reaction plays a significant role

and H2 yield increases significantly till carbon boundary point (at SBR of 1.5).

Carbon boundary at SBR of 1.3 has been reported in another study. The

equilibrium values at higher SBR’s are not used in the analysis performed

using EES software.

Extensive analysis was carried out on the availability and irreversibility

of the biomass gasification process. The exergy efficiencies of air and steam

gasification with pyrolysis were compared. Equilibrium studies were employed

using non-stoichiometric method based on minimizing the Gibbs free energy.

Steam gasification proved to be a more efficient process compared to air

gasification and pyrolysis. Steam gasification efficiency was reported as

87.2% compared to 80.5% for air gasification. In the case of pyrolysis, the

efficiency was 76.8%. The physical, chemical exergy and sensible enthalpy

of gas and their variation with SBR and ER were also analyzed. In the case

of air gasification, carbon boundary was identified at ER of 0.25 beyond which

no carbon is available for gasification. Beyond the carbon boundary point, the

efficiency decreased and losses were credited to oxidation of fuel gas to CO2

and H2O leading to higher sensible heat and lower chemical energy in the

product gas. Similarly, in the case of steam gasification, carbon boundary was

62

identified at SBR of 1.3 beyond which introducing extra steam led to loss in

input energy used in steam generation. The coupling of exothermic oxidation

of carbon with endothermic water-gas and Boudouard reaction was argued for

the better efficiency of gasification over pyrolysis. The researchers have not

been ableto clearly identify reasons towards higher efficiency achieved in the

case of steam gasification over air gasification.

Thermodynamic analysis was conducted for oxygen enriched air

gasification of pine wood. The oxygen fraction in gasifying media was

increased from ambient condition (21% O2) to 40% O2 on the mole basis; the

balance being N2. Increase in exergy and energy efficiencies with O2 fraction

was observed. Exergy efficiency of 76% with 21% O2 increased to over 83%

with 40% O2 while H2 and CO mole fractions in the product gas decreased

from 22% to 11% and 19% to 14% respectively. Increase in reaction zone

temperature with increase in O2 fraction was cited as the reason for higher

efficiencies. Specific reasons towards the reduction of H2 and CO with

increase in O2percent were not discussed. The higher efficiencies at higher

O2fractions seems inconsistent based on the analysis of exergy and energy

efficiencies with the variation in temperature.

It is evident from the literature on the exergy and energy analysis of

gasification systems that largely equilibrium analysis based results have been

used. The heterogeneous reaction system during gasification is very complex

and it cannot be approximated with the thermodynamic equilibrium model.

The gas composition, quality and hence the efficiency of a gasification system

depends significantly on the residence time of the reacting species at the

given temperature which inherently depends on the reactor geometry, design

and process parameters. The heterogeneous reactions that occur inside the

reactor are both diffusion and kinetic limited depending upon the reactants.

3.2.7 National Status (Including Commercialization Efforts by Industry)

The development of the technology (internationally), to harness this

route has taken place in spurts. The most intensive efforts were put during the

Second World War to meet the scarcity of petroleum sources for transport

needs of the civilian and military sectors. Some of the most studies on wood

gasifierswere basic as well as developmental related.

In India, during the initial developmental efforts, Department of Non-

conventional Energy Sources (now MNRE) took an important decision to field

test the technology developed by various research and industrial groups. This

was carried out during 1997 to 2000. The major emphasis was on the water

pumping application in the range of 5 to 50 HP. Around 1700 systems (35

63

MW equivalent) were installed in field under the MNRE’s demonstration

program on biomass gasification.

There has been an activity for developing reliable industrial package for

both power generation and thermal application in the later period of the year

2000. In the power generation sector, the emphasis shifted from dual fuel to

pure gas engine mode; in order to compete with the grid costs as the fossil

fuel prices increased. Gas engines could not accept producer gas as a fuel as

it was not commercially available and some of the research groups carried out

the R & D to operate engines on producer gas. While various groups

developed skills to adapt natural gas engine to operate on producer gas,

Indian Institute of Science, working with Cummins India Limited (CIL)

succeeded in developing a package for producer gas engines. Currently, CIL

would be the first Indian engine manufacturer to produce engines using

producer gas as fuel.

Apart from several other factors, MNRE’s role both in research,

development and implementation of the biomass gasification programme has

been very critical. There are only 4 – 5 groups involved both in the

development and implementation of the technology packages either directly or

using licensees. There have been differences in the technology packages

developed among these groups. M/s ASCENT, Sacramento, USA have

developed packages for woody biomass, fine biomass and a combination of

the two. A closed top gasification system has been used for conversion

process. Rice husk gasification system is designed separately to handle rice

husk as received. The Research Group at Tata Energy Research Institute has

developed technology packages for woody and briquetted biomass using

throat-less gasifier with closed top. The Sardar Patel Renewable Energy

Research Institute, Vallabh Vidhyanagar, Gujarat has been involved in the

development of technology packages for dual fuel and thermal application,

using both forced and natural drafts depending upon the requirements. Indian

Institute of Science, Bangalore has developed a multi-fuel gasification system

to accept woody biomass or biomass briquettes. The largest capacity power

plant connected to the grid using gas engines supplied by Cummins India

Limited has been built. Systems of varying capacity (up to 1 to 10 MWth) have

been developed. While there have been large numbers of gasifier systems

implemented by gasifier manufacturers, but very limited operational data is

available in the public domain for analysis and reporting, consolidating the

performance of the system/s and providing an account of operational

experience.

The IISc, Bengaluru has developed an open-top downdraft gasifier,

where residence time of gases increases inside the reactor and high

temperature of the char bed is maintained, which improves conversion

64

efficiency and reduces formation of higher molecular weight compounds.

Figure 3.1 provides an input on the use of dolomite as a bed material for fluid

bed gasification system to reduce the tar levels. It can be seen that the tar

level varies from 10 to 50g/m3 depending upon the bed material used in

typical fluid bed gasification.

Figure 3.1 Average benzene and tar concentration in per kg of dry gas

Use of air gasification system for power generation has been

established and options to biomass for various other outputs as indicated in

the Figure 3.2 which suggests various biomass conversion process to end

use energy efficiency.

It is evident that the biomass gasification based power cycle has the

conversion efficiency in the range of 40 % while the hydrogen generation

could be in the range of 60 %.

As stated earlier, very limited work has been carried out in the area of

hydrogen generation from biomass. Most of the activities are at bench scale

except some of the research carried on the existing steam gasification

platform, where a small portion of the gas is being taken through the gas train

for generating pure hydrogen. The overall yield of hydrogen is about 42 g/kg

of biomass.

The National Institute of Technology, Calicut is engaged in the

research activities of hydrogen production by thermo-chemical method in

fluidized bed gasifier under catalytic support and its utilization. Under this

activity a 7.5 kW capacity bubbling ptimizat fluidised bed biomass gasifier was

65

Figure 3.2: Biomass to fuel efficiency for various outputs from biomass

conversion processes

designed and developed for performance evaluation. The effect of process

parameters on air gasification of rice husk and air-steam gasification of saw

dust and coconut shell were studied. Stoichiometric thermodynamic

equilibrium models for air and air-steam gasification of different biomasses

were developed using MATLAB software validated with experimental data.

The developed models were used to analyse the effect of various process

parameters like gasification temperature, steam to biomass ratio and

equivalence ratio on gas composition, lower heating value and yield of syngas

and first and second law efficiencies. An Eulerian-Eulerian model for air-

steam gasification of sawdust was also developed using Fluent13 software.

The particle motion inside the reactor was optimized using various drag laws

derived from Kinetic Theory of Granular Flow. In these models biomass

pyrolysis was not considered.

3.2.8 Action Plan

3.2.8.1 Gap Analysis & Strategy to Bridge the Gap with Time Frame

In the recent times the focus at MNRE has been on generating

hydrogen rich syngas through thermo-chemical conversion of biomass.

Couple of research projects has been sponsored in this sector with the focus

on hydrogen production. In view of the abundant availability of biomass in the

country, work in this area needs to be consolidated and continued to fill in the

66

existing gaps in R&D and design and demonstrate pilot/full size units within a

reasonable time frame.

As a part of the MNRE supported R&D activity, Indian Institute of

Science, Bangalore has completed a project addressing the above aspects of

hydrogen production through the thermo-chemical conversion of biomass.

This has resulted in developing a prototype to generate hydrogen rich syngas

using oxy-steam gasification.

The entire process has been optimized to generate a maximum of

about 100 g hydrogen/kg biomass. The process has also been studied to look

at possibility of generating the hydrogen rich syngas for FT process as well

with H2:CO ratio of about 2.

Syngas composition, hydrogen yield and performance parameters

were monitored with varying steam to biomass ratio and equivalence ratio.

Experiments were conducted by varying SBR from 0.75-2.7 and ER ranging

from 0.18-0.3. Figure 3.3 shows the gas analysis data of an operation of over

4 hours.

Figure 3.3 : Gas composition using oxygen and superheated steam

(SBR = 1.45, ER = 0.25)

Experiments and kinetic studies in the complex heterogeneous

reacting system have been conducted with wet wood and oxygen as well as

with dry wood and oxy-steam. Table 3.2 summarizes the data from the

experimental results using wet wood with oxygen and dry biomass with

superheated steam. Results show that using dry biomass with oxy-steam

67

improves the H2 yield, efficiency and syngas LHV compared to direct usage

of wet biomass with oxygen.

Table - 3.2 : Results, analysis and comparison while using dry biomass with

superheated steam

Dry biomass with superheated steam

H2O to biomass ratio 0.75 1 1.4 1.5 1.8 2.5 2.7

ER 0.21 0.18 0.21 0.23 0.27 0.3 0.3

H2 yield (volume

fraction, %) on dry

basis

41.8 45.2 43.1 45.2 49.6 51.7 50.5

CO yield (volume

fraction, %) on dry

basis

27.6 24.9 26.5 24.9 17 12.8 13

H2 yield (g kg-1 of

biomass) –

Experimental result

66 68 71 73 94 99 104

H2 yield (g kg-1 of

biomass) – Equilibrium

analysis result

87 88 102 101 99 107 117

Percent of H2 yield from

moisture/steam (%)

(65.5 g H2 in biomass)

21.4 20.2 28 27.7 43.7 44.3 48.1

H2/CO 1.5 1.8 1.6 1.8 2.9 4.0 3.9

LHV (MJ Nm-3) 8.9 8.6 8.8 8.7 8 7.5 7.4

H2O volume fraction in

syngas (%) 0.8 1.4 1.6 2 1.9 2.3 2.4

Fraction of heat

available through

CO+CH4 in syngas for

steam generation

4.2 2.7 2.2 1.9 1.3 0.8 0.8

Hydrogen efficiency (%)

– 73.7 63.2 67.2 63.5 70.5 61.0 63.7

Gasification efficiency

(%) – 82 73 75 74 78 67 66

Exergy efficiency (%) - 85 81 80 77 84 78 70

Using dry wood and oxy-steam as gasifying agents, 104 g hydrogen

was obtained per kg biomass compared to a maximum of 63 g H2 per kg

biomass with wet wood and oxygen. The gasification efficiency with oxy-

steam gasification was found to be 85.8% compared to 61.5% with wet

biomass at H2O to biomass ratio of 0.75. Hydrogen yield in syngas, as high

68

as, 1.3 kg/h was achieved. Syngas with LHV of as high as 8.9 MJ Nm-3 was

obtained, which is almost twice the energy content in producer gas obtained

through air gasification. At lower SBR of 0.75, the low hydrogen yield of 66 g

per kg biomass was achieved with higher gasification efficiency of 85.8%

and higher LHV of 8.9 MJ Nm-3, and with an increase in SBR, H2 yield

increased to 104 g per kg of biomass with lower efficiency of 71.5% and

LHV of 7.4 MJ Nm-3. H2 fraction in syngas and H2/CO ratio is a very critical

parameter for the conversion of syngas to liquid fuel through FT synthesis.

Varying the SBR from 0.75-2.7, hydrogen fraction in syngas has been

obtained ranging from42-52% (molar basis) and H2/CO ratio is found to be

varying from 1.5 to as high as 4. At lower SBR values, the energy content in

CO and CH4 yield is sufficient for raising steam.

With the current experience of using biomass, about 70 g pure

hydrogen can be obtained per kg biomass, which results in about 15 kg

biomass for every kg of hydrogen generated.

Having generated hydrogen rich syn-gas, it is important to utilize this

gas for hydrogen production for applications like PEM fuel cells, SOFC, etc.

This calls for purification of the syngas to various levels depending upon the

end use.

3.2.8.2 Identification of the major institutions / industry for augmenting

R&D facilities including setting-up of Centre(s) of Excellence and

suggest specific support

Indian Institute of Science, which has been carrying out research

activity in the area of bio-energy for over three decades, is well positioned to

take the responsibility of Center for Excellence in the area of biomass to

hydrogen through various routes. IISc is concentrating on thermo-chemical

route of hydrogen production – Oxy–steam gasification of biomass, which has

been demonstrated with hydrogen yield of about 100 gms per kg of biomass

use. Apart from the various thermo-chemical routes that are being

researched, IISc also has groups working in the area of engines, materials,

storage, fuel cell, etc.

69

HYDROGEN PRODUCTION BY

ELECTROLYSIS OF WATER

70

71

4.0 Hydrogen Production by Electrolysis

4.1 Introduction

Hydrogen can be generated from water by electrolysis or thermolysis.

There are mainly three types of water electrolysis processes reported in

literature. These are classified as: alkaline, acidic (membrane based) and high

temperature ceramics (solid oxides) on the basis of electrolytes used. Of

these three types, development of the last one is still at the laboratory level. A

highly promising method of hydrogen production is electrolysis of water, using

power from solar photovoltaic cells (Figure 4.1).

Figure 4.1: Hydrogen generation using solar photovoltaic cells

4.1.1 Polymer Electrolyte Membrane based Water Electrolysis

Polymer electrolyte membrane (PEM) based water electrolysis offers a

number of advantages for the electrolytic production of hydrogen and oxygen

in comparison with the conventional water-alkali electrolysers, such as

ecological safety, high gas purity (more than 99.99% for hydrogen), the

possibility of producing compressed gases for direct pressurized storage

without additional power inputs and higher safety level. The membrane used

in these electrolysers is Nafion-brand perfluorinated ion-exchange membrane

of US Company DuPont (Figure 4.2). The PEM electrolysers based on solid

polymer electrolyte (SPE) technology were developed in 1966 by the General

Electric (USA) and designed for special purposes (spaceships, submarines,

72

etc.) as well as for industrial and analytical laboratory applications (in gas

chromatography).

Figure 4.2: Schematic drawing of PEM cell

Membrane based water electrolysis can be classified on the basis of

their electrolytes as alkaline (alkali / anion exchange membrane), or based on

proton / cation exchange membrane. In water electrolysis using cation

exchange membrane the oxygen and proton are generated at anode

(Equation 1), the generated proton then passes through the cation exchange

membrane and combines with electrons at the cathode to generate hydrogen

(Equation 2). The membrane acts as an electrolyte as well as a barrier for

preventing mixing of hydrogen and oxygen generated at cathode and anode

compartments respectively.

Anode (oxidation): 2 H2O(l) → O2(g) + 4 H+(aq) + 4e− --(1)

Cathode (reduction): 2 H+(aq) + 2e− → H2(g) --(2)

73

The electrode reactions in case of alkaline electrolysis are different

from those of acid electrolysis as shown in Equations 3 and 4. Here, cathodic

reduction of water generates hydrogen and hydroxyl ion (Equation 3), which

passes through an anion exchange membrane. At the anode hydroxyl ions

are oxidized (Equation 4) generating oxygen.

Anode (oxidation): 4 OH- (aq) → O2(g) + 2 H2O(l) + 4 e− --(3)

Cathode (reduction): 4 H2O(l) + 4e− → 2H2(g) + 4 OH-(aq) --(4)

The hydrogen thus produced in the process needs to be utilized in a

device that will convert it into electricity, e.g., fuel cells or it can also be utilized

in internal combustion engine.

Specifications of State-of-the-Art Alkaline and PEM Electrolysers as

reported in the NOW-study are given in Table 4.1.

Table 4.1: Specifications of State-of-the-Art Alkaline and PEM Electrolysers

as reported in the NOW-study.

Specifications Alkaline electrolysis PEM electrolysis

Cell temperature (0C) 60-80 50-80

Cell pressure (bar) <30 <30

Current density (mA/cm-2) 0.2-0.4 0.6-2.0

Cell voltage (V) 1.8-2.4 1.8-2.2

Power density (mW cm-2) <1 <4.4

Voltage efficiency HHV (%) 62-82 67-82

Specific energy consumption:

Stack (kW h Nm-3)

4.2-5.9 4.2-5.6

Specific energy consumption:

System (kW h Nm-3)

4.5-7.0 4.5-7.5

Lower partial load range (%) 20-40 0-10

Cell area (m2) >4 <0.03

H2 production rate: Stack-

system (Nm3 h-1)

<760 <10

Lifetime stack (h) <90000 <20000

Lifetime system (y) 20-30 10-20

Degradation rate (mV h-1) <3 <14

74

Advantages and Disadvantages of Alkaline and PEM Electrolysis are

given in Table 4.2.

Table 4.2: Advantages and Disadvantages of Alkaline and PEM Electrolysis.

The PEM electrolysers offer smaller, cleaner and more reliable

systems than competing electrolysis systems based on other technologies.

Alkaline electrolysers are relatively less expensive but consume more

electricity compared to PEM electrolysers wherein highly precious metals are

being used in PEM cell stack.

4.2 Alkaline Water Electrolysis

Electrolysis phenomenon was discovered by Troostwijk and Diemann

in 1789. Alkaline water electrolysis is one of the earliest methods employed

for hydrogen production. Sodium hydroxide or potassium hydroxide are used

75

as electrolytes and the cell is normally operated at about 700C. The alkaline

electrolyser cell consists of two nickel based electrodes separated by a gas-

tight diaphragm. This assembly is immersed in a liquid electrolyte that is

usually a highly concentrated aqueous solution of KOH (25–30 wt.%). It uses

microporous diaphragm to separate cathode and anode chambers. The

product gases are completely prevented from cross diffusing through

diaphragm. This results in the reduction of efficiency of the electrolyser. The

three major issues associated with alkaline electrolysers are i) low partial load

range, ii) limited current density, and iii) low operating pressure. The energy

required to produce 1 nM3 hydrogen /h is around 6 kWh. This is a matured

technology with a large number of industries supplying these electrolyser units

for a wide variety of applications. These electrolysers are less expensive as

non-noble metal catalysts are normally used. Alkaline electrolysis has been

used extensively for hydrogen production commercially up to the megawatt

range.

4.2.1 Challenges

The major challenges with alkaline water electrolyser (AWE) are

corrosion related issues and poisoning of the electrolytes by inadvertent

incursion of CO2. The energy required to produce hydrogen is still high

compared to the theoretical requirements. The other issue is developing high

pressure systems. Present method involves a separate receiver and

compressor sections in the electrolysis plant. This requires development of

polymeric membranes with anion exchange capability.

4.2.2 Current Technology

State of the Art Alkaline Electrolyser, Efficiency: 60-70% (LHV)

Operating temperature: up to 80oC

Operating pressure: 1 – 25 atm

Cost: ~$1000 - 2500/kW

4.2.3 Future Technology: Increasing the Capacity & Efficiency and

Reduction in Cost

System efficiency should reach 70-80% (LHV) by advanced

electrolyser technology

Industrial size electrolyser (MW level)

Cost should be reduced to $300 - 500/kW (Cost of Hydrogen at $2/kg)

76

4.3 Polymer Electrolyte Membrane (PEM) based Water Electrolysis

The drawbacks of alkaline electrolysers were overcome by the

development of solid polymer electrolyte concept by General Electric, USA, in

the 1960’s. The membranes used were sulfonated polystyrene membrane.

This concept is also referred to as proton exchange membrane or polymer

electrolyte membrane (both with the acronym PEM) water electrolysis, and

less frequently as solid polymer electrolyte (SPE) water electrolysis. The

polymeric membrane based water electrolysers till now have used cation

exchange membrane. Water electrolysis with a polymer electrolyte membrane

(PEM) cell possesses certain advantages compared with the classical alkaline

process like increased energy efficiency and specific production capacity and

simplicity in construction with a solid electrolyte operating at a low

temperature. Direct application to water electrolysis was not possible at that

time because available Solid polymer electrolytes (SPEs) were lacking

sufficient chemical stability. This was mainly due to very oxidizing conditions

found at the anode of water electrolyser where oxygen is evolved at high

electrode potential values (close to +2 V vs. NHE). At the end of the sixties,

more stable sulfonated tetrafluoroethylene based fluoropolymer-copolymers,

(E.I. DuPont Co., Nafion®) products were made available for water

electrolysis applications. This membrane exhibits high chemical stability both

in strong oxidizing and reducing conditions up to 1250C.

Ultra-pure water is fed to the anode compartment of the electrolysis

cell, which is made of porous titanium and activated by a mixed noble metal

oxide catalyst. The membrane conducts hydrated protons from the anode to

the cathode side. Appropriate swelling procedures have led to low ohmic

resistances enabling high current density of the cells. The standard

membrane material used in PEM water electrolysis units is Nafion® 117 and

is manufactured by DuPont, USA. The cathode of such an electrolyser

consists of a porous current collector with either Pt or, in more recent designs,

a mixed oxide as electrocatalyst. Individual cells are stacked into bipolar

modules with titanium based separator plates providing the manifolds for

water feed and gas evacuation.

The polymer electrolyte membrane (Nafion, Fumasep) have high

proton conductivity, low gas crossover, compact system design and high

pressure operation. The low membrane thickness (~20-300 m thick) is in part

the reason for many of the advantages of the solid polymer electrolyte.

PEM electrolysers can operate at much higher current densities,

capable of achieving values above 2 A cm-2, this reduces the operational

costs and potentially the overall cost of electrolysis (Tables 4.1 and 4.2).

Ohmic losses limit maximum achievable current densities, with a thin

77

membrane capable of providing good proton conductivity (0.1 - 0.02 S cm-1),

higher current densities can be achieved. The solid polymer membrane allows

for a thinner electrolyte than the alkaline electrolysers.

The low gas crossover rate of the polymer electrolyte membrane

results in yielding hydrogen with high purity, as described in Table 4.2 and

allows for the PEM electrolyser to work under a wide range of power input.

This is due to the fact that the proton transport across the membrane

responds quickly to the power input, not delayed by inertia as in liquid

electrolytes. As discussed above, in alkaline electrolysers operating at low

load, the rate of hydrogen and oxygen production reduces while the hydrogen

permeability through the diaphragm remains constant, yielding a larger

concentration of hydrogen on the anode (oxygen) side thus creating a

hazardous and less efficient conditions. In contrast with the alkaline

electrolysis, PEM electrolysis covers practically the full nominal power density

range (10-100%). PEM electrolysis could reach values over 100% of nominal

rated power density, where the nominal rated power density is derived from a

fixed current density and its corresponding cell voltage. This is due to low

permeability of hydrogen through Nafion (less than 1.25 x 10-4 cm3s-1cm-2 for

Nafion- 117, standard pressure, 800C, 2 mA cm-2).

4.3.1 Drawbacks

Problems related to higher operational pressures in PEM electrolysis

are:

1. Cross-permeation phenomenon, which increases with pressure.

2. PEM membranes being highly acidic are corrosive and require

use of distinct materials. These materials must not only resist the

harsh corrosive low pH condition (pH ~ 2), but also sustain the

high applied over-voltage (~2 V), especially at high current

densities.

3. The catalysts used, current collectors and separator plates also

need to be corrosion resistive.

4. Only a few materials can be selected in this harsh environment,

such as noble catalysts (platinum group metals-PGM e.g. Pt, Ir

and Ru), titanium based current collectors and separator plates

(Figure 4.3).

78

Figure 4.3: Component overview for a typical PEM water electrolyser.

Numbers of publications as a percentage of total publications directly

related to PEM water electrolysis over the years including the percentage

published related specifically to modeling (source: ISI web of knowledge) are

given in Figure 4.4.

79

Figure 4.4 : Number of publications as a percentage of total publications

directly related to PEM water electrolysis over the years

including the percentage published related specifically to

modeling (source: ISI web of knowledge).

Performance range of published polarization performance curves from

2010 to 2012 for a PEM electrolysis single cell operating with Ir anode, Pt

cathode, and Nafion membrane at 800C is given in Figure 4.5.

Figure 4.5 : Performance range of published polarization performance curves

from 2010 to 2012 for a PEM electrolysis single cell operating

with Ir anode, Pt cathode, and Nafion membrane at 80oC

80

4.4 Hydrogen Utilization

Fuel cells have emerged as an alternative source of energy/energy

conversion devices in portable as well as stationary mode. A variety of fuel

cells such as phosphoric acid fuel cell (PAFC), alkaline fuel cell (AFC),

molten carbonate fuel cell (MCFC), solid oxide fuel cell (SOFC) etc. have

been developed and a few of them are commercially available. Other than

PAFC, all the commercially available fuel cells such as MCFC or SOFC

operate at high temperatures and therefore their use remains limited to

stationary power generation applications. Electrolyte leakage is a major

drawback of the liquid electrolyte fuel cells. Proton Exchange

Membrane(PEM) Fuel Cells otherwise known as solid polymer electrolyte fuel

cells can operate at temperatures close to 80oC has large number of

applications in civil, aviation and military areas both in portable and stationary

power generation mode. Constant research and development activities across

different laboratories of the world are in progress to prepare cost effective

eco-friendly membranes to make affordable PEMFCs.

4.5 High Temperature Water Electrolyser (HTWE)

Using solid oxide fuel cells (SOFC) in the reverse mode is a recent

trend in hydrogen generation. The HTWE has an advantage over alkaline and

PEM electrolysers, because they can achieve a higher efficiency and lower

capital costs over a wider range of current densities and cell voltage. The high

temperature electrolysis splits steam at a temperature above 800oC. This

process uses calcium and yttrium stabilised zirconium oxide (YSZ)

membranes. Operation of the cell at high temperatures (900–1000°C) reduces

the amount of electricity needed to produce hydrogen by about 30% as

compared to electrolysis process at room temperature. Electricity consumed

is about 2.6-3.5 kWh/Nm3 of hydrogen produced. Nuclear reactors operating

in the same temperature range are ideally suited for this purpose.

4.6 International Status

International status of the published work available in open literature is

summarized in Table 4.3.

The largest existing alkaline electrolysis plants are: KIMA fertilizer plant

in Aswan, Egypt with a capacity of 160 MW and 132 modules, and a 7 module

22 MW plant in Peru (pressurized operation). Another highly modularised unit

is the Brown Boveri electrolyser, which can produce hydrogen at a rate of

about 4–300 m3/h.

81

Table 4.3: List of Companies Manufacturing Alkaline Electrolysers

Manufacturer Cell Type Rated

production

(Nm3/h)

Location

AccaGen

Avalence

Claind

ELT

ELT

Erredue.

NEL Hydrogen

Hydrogenics

H2 Logic

Idroenergy

Industrie Haute

Technologie

Linde

PIEL, division of ILT

Technology

Sagim

Teledyne Energy

Systems

Norsk Hydro ( 0.5 to1

bar, 61-72 LHV

efficiency)

Stuat Energy ( 1 to 25

bar ; 73-75% LHV

efficiency)

alkaline (bipolar)

alkaline (monopolar)

alkaline (bipolar)

alkaline (bipolar)

alkaline (bipolar)

alkaline (bipolar)

alkaline (bipolar)

alkaline (bipolar)

alkaline (bipolar)

alkaline (bipolar)

alkaline (bipolar)

alkaline (bipolar)

alkaline (bipolar)

alkaline (monopolar)

alkaline (bipolar)

alkaline (bipolar)

alkaline (bipolar)

1-100

0.4-4.6

0.5-30

3-330

100-760

0.6-21

10-500

10-60

0.66-42.62

0.4-80

110-760

5-250

0.4-16

1-5

2.8-56

Upto 485

Upto 50

Switzerland

USA

Italy

Germany

Germany

Italy

Norway

Canada

Denmark

Italy

Switzerland

Germany

Italy

France

USA

Norway

USA

The PEM water electrolyser was developed before 1966 and

introduced by General Electric Corporation, USA. In 1979 the cells operating

at 1A.cm-2 800C at 1.8V was reported. Based on this technology high pressure

electrolysis cells were designed and tested. All these efforts were basically for

NASA, US Navy aircraft carriers and nuclear submarines for hydrogen

generation and oxygen supply for life support systems. Several types of cell

and system configurations were evaluated and an ultimate size of one cell unit

was found to be 0.23 ft2. The Nafion-120 membranes with catalysts of

platinum, platinum-iridium-tantalum etc. were used for the membrane-

electrode assembly. The preparation of the membrane–electrode composites

was very expensive. By the end of this project economic evaluation indicated

a prohibitively high cost of such units. This system was suitable only for

82

specific applications, where cost is secondary and so the technology could not

attain commercial status for large scale hydrogen generation.

Billings Energy Corporation, Provo, Utah, USA also described their

version of PEM electrolyser having Nafion membrane coated with lead-

dioxide anode and nickel cathode catalysts, the performance of which was

very poor. The cell showed about 5.0V at 400mA/cm-2 at 500psig. On using

platinum for both anode and cathode they could improve the performance to

about 3.25V at 600 mA/cm2with an efficiency of efficiency of 45%. Because of

the high loading of the noble-metal catalysts and the higher resistance of the

membranes, the efficiency and economics were far from acceptable standard.

United Technologies Corporation, East Hartford, USA was reported

to be engaged in the development of PEM electrolyser modules, probably with

the GE concept, with 22 cells of 0.23ft2 each for US navy and space

applications and also described a regenerative fuel cell unit of 1-2 kW

capacity.

ABB Switzerland was also active in the PEM electrolyser

development during 1976 to 1998. The ABB technology has been

demonstrated in two commercial versions of 100kW capacity at Stellram SA,

Nyon, Switzerland and Solar-Wasserstoff-Bayern GmbH. The general design

features are: Nafion-117 with platinum cathode catalyst and graphite current

collector and the anode was Ru-Ir mixed oxide with porous titanium anode

current collector. At 1 A.cm-2 and 800C, the cells exhibited 1.75V. Both

plants had to be stooped after three years of operation from 1987 due to the

high level of hydrogen in oxygen (>3%) and the membrane was found to have

been damaged in part of the cells. The cells were refurbished and operated till

1998. The cause of failure of the cells was found to be related to the

assembling faults causing mechanical stresses and also due to the

membrane degradation.

The Electrolysis 2000 project was initiated in France and different

aspects of the system were investigated at various laboratories during the

90’s. Laboratory cells have been tested with typical voltage of 2.1V at 1

A.cm-2. The European Commission (EC) is actively supporting different

projects within the 6th and 7th Framework Programmes. The main deliverable

of the GenHyPEM project was on the development of a PEM water

electrolyser with a hydrogen production capacity ranging from 0 up to 1

Nm3H2/hour, operating in the 0-90oC temperature range and the 1-50 bars

pressure range and this project was carried out by the Institut de

ChimieMole´culaire et des Mate´riaux, France in 2008. Apart from these

developments, many research laboratories and academic institutions and

universities are engaged in studies on both the fundamental and applied

aspects of the PEM water electrolyser system.

83

The recent reports of the commercial availability of small and medium

range PEM water electrolysers for laboratory utility and for other applications

are from three major industries.

Proton Energy Systems, USA is currently offering 0.5, 1 and 10 m3

per hour hydrogen delivery systems, suitable for power generation through

fuel cells. This may be the so called state-of the-art hydrogen generator with a

number of advanced features for safe and efficient generation of hydrogen.

The system delivers hydrogen at a high purity (99.999%) and pressure of 170

to 200 psi with an overall average energy requirement of 5.7 to 6.4 kWh/Nm3

H2 for the 1 Nm3/hr H2 generators. M/s ITM power, UK is also offering PEM

based Water electrolyser system in the range of 11- 75 Nm3 H2/h capacity.

Hamilton Sundstrand, a subsidiary of United Technology Corporation, East

Hartford, USA has reported to be offering a system containing stacks upto 65

cells of 0.23 ft2 active area, operating up to 3 A.cm-2 that can deliver hydrogen

up to 750 psig. This system is intended mainly for strategic applications.

The third report is from Fuji Electric Corporate Research and

Development, Japan is about the development of 25 dm2 PEM water

electrolyser under the WE-NET program. The electrolytic cells were fabricated

with their own experimental membranes with low equivalent weight, low

thickness & high ionic conductivity and reports a test cell performance of

1.555 to 1.58V at 1 A.cm-2 and 80oC. All the cell hardwares are based on the

most improved structure and fabrication techniques.

Siemens, FRG plans to build an electrolyser system to store wind

power as hydrogen. The system will have a peak rating of up to 6 MW. The

project, which will cost 17 million, is being financed with the support of the

German Federal Ministry of Economics and Technology as part of the Energy

Storage Funding Initiative. The system involves highly dynamic PEM high-

pressure electrolysis that is particularly suitable for high current density and

can react within milliseconds to sharp increases in power generation from

wind and solar sources.

Currently available PEM water electrolyser systems have a hydrogen

production rate that varies from 0.06 to 75 Nm³/hr. This is very low in

comparison to alkaline electrolyser production rates that have already

reached 500 Nm³/h. With regard to the lifetime, the membrane represents the

critical component of PEM system. Even though the lifetime of PEM

electrolysis systems were significantly improved in the last 10 years, it is still

limited due to the nature of solid polymer electrolyte membrane, and it is

below 20,000 h. PEM electrolysers are less mature, produced in smaller

quantities, and therefore more expensive than alkaline electrolysers. It is

expected that the lifetime will be prolonged up to 60,000h in the long term

84

predictions. Even though there is no clear relation between operating

conditions and degradation processes of the stack, in some cases operating

conditions can lead to membrane perforation.

The concept of high-temperature electrolysis production of hydrogen

from steam was investigated first in the 1980s by Dornier System GmbH,

Friedrichshafen, Postfach, Germany in the project called ‘‘High Operating

Temperature Electrolysis, HOT ELLY’’. After that Westinghouse Electric Co.

and Japan Atomic Energy Research Institute (JAERI) made efforts to carry

out HTWE experiment through tubular single cells and planar cells. Then the

research and development efforts on HTWE became slow due to the cheap

and sufficient supply of fossil energy. Now once again the HTWE technology

for hydrogen production is becoming popular again, because of two major

context changes the prospects of transition to a hydrogen-based economy

due to the shortage of fossil energy and the prospects for the development of

advanced primary energy to supply highly efficient heat sources. In 2004,

researchers at the U.S. Department of Energy’s Idaho National Laboratory

(INL) and Ceramates, Inc. of Salt Lake City, USA announced a breakthrough

development in hydrogen production from nuclear energy. They have

demonstrated a 15 kW integrated laboratory scale (ILS) facility with a

hydrogen production rate of 0.9 Nm3/h.

They achieved the highest-known production rate of hydrogen by

HTSE with an electrolysis efficiency of almost 100%. This development is

viewed as a crucial first step toward large-scale production of hydrogen from

water, rather than fossil fuels and a milestone in the hydrogen energy

research field. Department of Energy (DOE) of the United States hoped that

INL can commercially produce hydrogen production by HTSE before 2017 to

reduce the dependence of fossil fuel. In Jan, 2005, the news of large-scale

hydrogen production through HTSE by nuclear reactor was voted by 584

Chinese academicians and chosen as one of the ten biggest scientific news of

the world in 2004, which indicated the deep concern about the hydrogen and

nuclear energy development progress in China. Subsequently, GE Company,

a joint effort of University of Nevada, Las Vegas and Argonne National

Laboratory, European Union (the coordinator including European Institute for

Energy Research, Swiss Federal Laboratories for Materials Testing and

Research, Deutsches Zentrum fur Luft- und Raumfahrt and Rise National

Laboratory, the University of Iceland and Icelandic New Energy, French CEA,

Japan and Korea successively initiated HTWE research programs around

2005.

Institute of Nuclear and New Energy Technology (INET), China started

R&D projects for nuclear hydrogen production in 2005. Thermo-chemical

water splitting by an iodine-sulfur (IS) process and HTSE process using

85

SOEC are mainly concerned currently with the heat utilization system of

nuclear reactor (HTR-10). In the last three years, HTWE research group

experienced preliminary investigation, feasibility study, equipment

development and hydrogen production technology.

Cylindrical design was favored for the prototypes model in the 1980s.

Current investigations focus on planar designs. Planar type HTWE technology

is being utilised, because it has the best potential for high efficiency due to

minimised voltage and current losses. These losses also decrease with

increasing temperature.

Perflurosulfonated membranes were synthesized from

tetrafluoroethylene as the starting material. These membranes have a PTFE

like back bone with side chains terminating with sulfonic acid groups. Besides

Du Pont, Asahi Glass and Dow Chemical’s also developed similar

membranes. However, the length of the side chains and the distance between

the side chains were different (Table 4.4). The equivalent weight of these

electrolyte membranes ranged from 800 to 1200g equivalent of protons in dry

form. Thickness was in the range of 50 to 260 m. Apart from

perfluorosulfonated membrane like Nafion there are several other electrolyte

membranes made either from perfluorinated or non-fluorinated chemicals and

are commercially available. Some of these electrolyte membranes are given

in Table 4.5. The hydrophilic region having sulfonic acid groups forms clusters

in the presence of water. The overlapping clusters form a transport channel

responsible for the proton transport in the membrane. Since the proton

transport takes place through the cluster region, the conductivity is highly

sensitive to the water content of the membrane. The fluorinated polymers

have shown the best of the performance in the fuel cells (>5000 hrs of

operation). However, there is a need to develop alternate non fluorinated

polymers. Besides high cost, the fluorinated membranes contribute to

environmental burden during their preparation as well as disposal of the

polymers. It is recently reported that fluorinated compounds such as

hydrofluoric acid and other fluorinated fragments are released in the water

during operation. There has been constant effort to develop alternate

polymers by various researchers around the world and their method of

preparation is tabulated in Table 4.6.

86

Tab

le 4

.4: S

che

ma

tic s

tructu

re o

f pe

rflu

oro

su

lfo

nic

acid

me

mb

rane

s m

an

ufa

ctu

red b

y d

iffe

ren

t co

mp

an

ies.

87

T

ab

le 4

.5:

Co

mm

erc

ially

Ava

ilab

le S

PE

Ma

terials

88

Table 4.6: Different Membranes and their Detailed Description.

Sl.No. Membrane Description

Perfluorinated Membranes/Partially Fluorinated Polymers

1 Gore-Select Membrane Composite membrane; a base

material preferably made of expanded

PTFE that supports perfluorinated

sulfonic acid resin, PVA etc.

2 BAM3G (Ballard Inc) Polymerization of ,,-

trifluorostyrene and subsequent

sulfonation

Grafted Polymers

3 ,, - Trifluorostyrene

grafted membrane

Grafting of ,,-trifluorostyrene and

PTFE/ethylene copolymers

4 Styrene grafted and

sulfonated poly(vinylidene

fluoride) membranes [PVDF-

g-PSSA]

Pre-irradiation grafting of styrene onto

a matrix of PVDF after elec-tron beam

irradiation. The proton conductivity

can be increased by crosslinking with

DVB

Non-fluorinated

5 -methyl styrene blend

PVDF

Partially sulfonated -methyl styrene

composite with PVDF

6 Sulfonated poly(ether

etherketone) (SPEEK)

Direct sulfonation of PEEK in conc.

sulfuric acid medium

7 Sulfonated poly(ether

sulfone)

Partially sulfonated polysulfones

8 Sulfophenylatedpolysulfone Sulfophenylation of polysulfone

9 Methylbenzenesulfonated

PBI/methylbenzenesulfonate

poly(p- phenyleneterephthal

amide) membranes

These alkylsulfonated aromatic

polymer electrolyte posses very good

thermal stability and proton

conductivity when compared to PFSA

membranes, even above 80 ◦C

10 Sulfonated napthalenic

polyimide membrane

Based on sulfonated aromatic

diamines and dihydrides. Its

performance is similar to PFSA

11 Sulfonated poly(4-

phenoxybenzoyl-1,4-

phenylene) (SPPBP)

Derived from poly(p-phenylene) and

structurally similar to PEEK. Direct

sulfonation to produce the electrolyte.

89

12 Poly(2-acrylamido-2-

methylpropanesulfonic acid)

Made from polymerization of AMPS

monomer. AMPS monomer is made

from acrylonitrile, isobutylene and

sulfuric acid

Acid Base Blends

13 Imidazole doped sulfonated

polyetherketone (SPEK)

Complexation with imidazoles to

obtain high proton conductivities

14 Sulfonated poly(ether

etherketone) (SPEEK)-PEI

Sulfonated poly(ether etherketone)

(SPEEK)-Poly ethylene imine (PEI)

blended

15 Sulfonated poly(ether

etherketone) (SPEEK)-PBI

blend

Composite membranes based on

highly sulfonated PEEK and PBI

16 PBI-H3PO4 PBI doped with phosphoric acid

4.7 National Status

R&D on alkaline electrolysers in India dates back to early eighties.

BARC and CECRI were very active in developing materials for this type of

electrolysers as well as stacks. Compact alkaline electrolysers have been

designed and demonstrated in Chemical Engineering Group (ChEG), BARC

in the late eighties. BARC has developed water electrolysers with high

current density based on indigenously developed advanced electrolytic

modules incorporating porous nickel electrodes. A 40-cell electrolysis module

incorporating Porous Nickel Electrode operates at a high current density of

4500 A/m2 which is much higher than conventional cells in the market (1500

A/m2 or below). The electrolyser operates at 550C and 0.16 MPa to produce

10 Nm3/h of hydrogen. They have also now developed alkaline water

electrolyser of 30 Nm3/hr capacity and this technology is available for

production.

In 1990’s CSIR-CECRI had reported a new Lanthanum Barium

Manganate based oxygen evolution catalyst and Nickel-Molybdenum-Iron

based composite based cathode materials for alkaline water electrolysis. They

also developed a monopolar unit alkaline water electrolytic cell and

demonstrated the performance of 1.8 V at 300 mA.cm-2 in 6 M KOH at 303 K.

In 2008, CSIR-CECRI transferred process know-how for development

activated nickel electrode for alkaline water electrolysis to M/s Eastern

electrolyser, Noida.

Energy Research and Development Association (ERDA), Vadadora

has demonstrated the concept of wind hydrogen using commercial alkaline

water electrolyser (AWE) for practical distribution generation system in 2013.

90

This project was financially supported by MNRE. The integrated system

consisted of wind turbine (2X5kw), alkaline water electrolyser (1.1Nm3/hr),

hydrogen storage tank (1Nm3, at 5kg/cm2), battery bank (6x 200Ah at 12 V)

and IC engine (650VA) and it was installed at Savli (about 30 km away from

Vadodara, Gujarat). The battery was used to provide consistent electrical

power output and avoid short term intermittent fluctuations. Hydrogen fuelled

IC engine was operated when wind along with battery is not able to meet the

load demand.

The National Institute of Solar Energy, Gwalpahari, Gurgaon has

installed a 120 kW solar photovoltaic systems to produce electricity for

generation of hydrogen through the water electrolyser and is geared up to

demonstrate and evaluate the performance of various technologies of

hydrogen energy. The hydrogen, so generated will be stored in high pressure

cylinders. As and when required, it would be utilized for stationary power

generation through fuel cell and dispensed through the dispenser unit into

hydrogen fuelled vehicles (3-wheelers & 4-wheelers), meant for

demonstration.

The following companies are reported to be engaged in manufacturing

AWE for various industrial applications:

Company Production capacity

M/s. Sam Gas Projects Pvt. Ltd., Ghaziabad -

201 015, Uttar Pradesh

M/s. Rak Din Engineers, New Delhi

M/s. Vaayu Tech Engineering, Ghaziabad, Uttar

Pradesh

M/s. S. S. Gas Lab Asia, Delhi - 110 095

M/s. Vemag Engineers Private Limited, Baroda,

Gujarat

M/s. Eastern Electrolyser limited, Noida, Uttar

Pradesh 201301

1 to 50 Nm3 / h

0.072Nm3/h

50 Nm3/h

10Nm3/h

1-50 Nm3/h

--

The CSIR-CECRI developed a PEM based hydrogen production

(capacity 40 and 80 litres/h) water electrolyser system under a MNRE funded

project during 2003-2006. Subsequently they have developed 1.0 and 5.0

Nm3/hr capacity PEM water electrolyser under 11th Five year plan CSIR

Network Project during 2012 and demonstrated the same with the energy

consumption of 5.75 kWh/Nm3 of hydrogen. The electrolyser was designed

using circular type platinum coated titanium flow field plate, platinum black

cathode and iridium oxide anode. The developed electrolyser stack can

deliver the hydrogen at 5-10 bar pressure. Recently this technology has been

91

transferred to M/s. Eastern electrolyser, New Delhi and this company has

started to work with CSIR-CECRI for further development. In addition, CSIR-

CECRI has also demonstrated solar power integrated PEM based water

electrolyser system of 0.5 Nm3/h capacity in 2012.

SPIC Science Foundation ( SSF) was also engaged in development of

PEM based water electrolyser for hydrogen generation and developed

electrolyser stacks of capacity 500 lit/hour (0.5 Nm3/hour) Hydrogen and 1000

lit/hour (1 Nm3/hour) Hydrogen, under DST-TIFAC funded project . They used

platinised Titanium plate as bipolar plate. The proto-type 0.5 Nm3/h capacity

hydrogen generator was demonstrated at the Indian Meteorological

Department (IMD), Thiruvananthapuram in Feb’ 2006, to utilise the hydrogen

for lifting the weather balloons used to collect atmospheric data.

Centre for environment, Institute of Science and technology, JNTUH,

Hyderabad has also developed indigenous PEM based water electrolyser of

36 lit/h Hydrogen Production capacity using Nafion 115 under BRNS funded

project in 2010.

Hydrogen generation using PEMWE concepts using depolarisers have

also been reported from some Indian labs. This types of work has also been

reported from some labs in USA. For the first time, SSF developed and

demonstrated PEM based water electrolyser system, which used methanol as

a depolariser. In this method, pure hydrogen can be generated with a much

lower energy consumption compared to water electrolysis. Electrolyser stack

was developed using titanium flow field plate, carbon supported Pt-Ru and

Carbon supported Platinum catalyst for anode and cathode respectively. This

was demonstrated with the hydrogen production capacity of 60.0 lit/h under

MNRE funded project during 2006. The energy consumption for hydrogen

production was 2.0 kWh/Nm3.

In 2012, The Centre of Fuel Cell Technology, Chennai (a project of

International Advanced Research Centre for Powder Metallurgy, Hyderabad)

demonstrated of 1.0 Nm3/h hydrogen production capacity electrolyser using

similar concept but with much lower energy consumption of 1.40 kWh/Nm3. It

also demonstrated for the first time use of carbon based materials in its

construction and thus redcuing the capaital cost tredomnously. ARCI-CFCT is

carrying out a large amount of work in identifying suitable depolarisers, which

can redcue the cost of hydrogen .

Sea water electrolsyis to produce hydrogen is being pursued at CSIR-

CECRI and the Centre of Fuel Cell Technology, Chennai. Novel

electrocatalayts have been developed . However the energy cost remains still

high .

92

M/s. MVS engineering Ltd , New Delhi offer turnkey supply for PEM

technology in partnership with proton onsite (USA) for customers looking for

non-alkaline solution for hydrogen generation by water electrolysis.

Indian Oil’s R&D Centre recently commissioned India’s first Hydrogen

fuel dispensing station at its R&D Centre at Faridabad. The pilot station

provides a hands-on experience with on-site Hydrogen production, storage,

distribution and supply. The hydrogen is being produced by water electrolysis

method using imported PEM electrolyser system.

In general, the production of hydrogen through electrolysis of water is a

highly energy intensive method (4.5-6.5 kWh/Nm3). Because of its high

energy consumption and also of the quite substantial investment, water

electrolysis technology is not widely used in India for commercial purposes.

The challenges for widespread use of water electrolysis are also the

durability.

BARC has a roadmap for development of solid oxide fuel cell and

development of materials and methods are underway for SOFC power packs.

They have a plan to utilise this development for the development of High

temperature steam electrolyser of 1.0 Nm3/h hydrogen production capacity for

technology demonstration purposes. Development of proton conducting high

temperature materials is another major R&D thrust. Besides BARC, CGCRI,

IIT-D has initiated some work in this area recently.

4.8 Gap Analysis & Strategy to Bridge the Gap

Identification of projects and prioritize them for support with the result

oriented targets.

Identification of the major institutions / industry for augmenting R&D

facilities including setting-up of centre(S) of excellence and suggest

specific support.

Partnership with foreign institutions including technology adaption from

abroad.

Identification of the institutions for setting up of demonstration plants.

Identification of institutions / industry to work on PPP model for

commercialization of the developed processes.

Identification of technologies for adoption in specific applications with

time line.

The electrolyser system consists of various subsystems like

electrochemical stack, power rectifiers, control systems, instrumentation for

monitoring various processes, water purification, pumps, multistage

compressors, pressure vessels, and multiple number of other engineering

93

subsystems involved while integration as per customer requirements to

develop complete system. Except for the electrochemical stack, couple of

PSU’s in India has core strength for manufacturing majority of aforementioned

subsystems and very much capable in system engineering. Imported

electrolyser stacks in different combinations may be used and integration can

be carried in the country.

4.9 Action Plan

Development of alternate solid polymer electrolytes that are stable in

the electrolysis cells more than 5000 hours of operation would be of desirable.

The SPE is either acid or alkaline based, the acid based electrolysis system

requires noble metal catalysts, and alkaline membrane based electrolysis

require cheaper electro-catalyst like nickel. It is ideal to have alkaline

membranes based water electrolysis system that works on the solar energy

derived from solar cells. However, presently alkaline based SPE faces

numerous challenges such as chemical stability in the electrochemical device.

These challenges are lesser for either phosphoric acid based electrolysis cells

or alkali based electrolysis systems using diaphragm. Due to this the following

path is suggested with an idea of immediate goals of onsite hydrogen

production using presently available technology and replacement of the

traditional technology with the membrane based electrolyser in a phase wise

manner. Following steps are envisaged.

(i) Solar energy based

(a) Acid based electrolysis system

(b) Alkali based electrolysis system

(ii) Development of electrolysers based on indigenous acid based SPE

(iii) Development of alternate alkaline membrane

(iv) Development of alkaline SPE based electrolyte system

(v) Replacement of traditional systems as in 1 by the new membrane

based system

4.10 Possible Incentives to Promote Industry Participation

Industry participation is the most essential factor for the successful

implementation as well as utilisation of the hydrogen produced using the

electrolysis method. Currently industry uses other methods for the production

of hydrogen; such industries can earn carbon credits by use of electrolysis

based hydrogen production.

(i) To begin with government can set up few demonstration plants in

an industrial area to augment the hydrogen produced by these

industries for their own production.

94

(ii) A comparative study of this method with the age old methods can

carried out and an educative program can be undertaken to show

the techno-economic feasibility of the electrolysis method.

(iii) Subsidy may be provided or the industry may earn carbon credits

for putting up such plants.

4.11 Summary & Conclusions

Solid polymer electrolyte (SPE) based electrolysis process is a clean

process of hydrogen production when coupled with photovoltaic based solar

cells. Development of solid polymer electrolytes both acid and alkali based

would be the key for successful development of these systems. Alkali based

electrolytes are preferred over the acid based ones due to the use of non-

noble catalysts, however alkali based SPE faces challenges such as chemical

stability in the electrochemical system. The acid SPE based electrolyser may

be deployed on a small scale in a distributed hydrogen production systems

both in industry as well as for remote areas. It is suggested to setup hydrogen

production plants based on presently available electrolysers which can be

manufactured in India and then replace these conventional electrolyser with

the SPE based electrolysers in a phase wise manner. This will ensure the

successful deployment of technology in time to come.

4.12 Cost Estimate of Hydrogen Generation

Hydrogen Generation on a 1 MW system

Assumptions

Utilization

factor

75% Plug

Cost of

Electricity ($/kW) $ 0.12 Plug

Efficiency % 77% Calculated

Efficiency kWh/kg 51.0 Plug

CapEx

10 year program

kg / Day Cost kg of H2 $ / kg

1 MW System 450 $ 1,975,000 1,231,875 1.603247

Opex

Cost Total Cost $ / kg

Maintenance per year $ 35,000 $ 350,000 0.28412

Spare Parts over proyect $ 60,000 $ 600,000 0.487062

Electrical Cost

$ 753,908 $ 7,539,075 $ 6.12

Water Cost

$ 54,750 $ 547,500 $ 0.44

Total Cost of per kg of H2 produced $ 8.94

95

BIO-HYDROGEN AND BIO-METHANE

PRODUCTION

96

97

5.0 Bio-Hydrogen and Bio-Methane Production

5.1 Biological Hydrogen production process has gained importance in

recent years. In early 1990s biological hydrogen production came in lime light

in energy policy of many government institutions throughout the world.

Biological H2 production takes place mainly at ambient temperature and

atmospheric pressure which makes this process less energy intensive than

other conventional processes (chemical or electrochemical process).

Microbial species capable of producing H2 belong to different taxonomic and

physiological types. Pivotal enzyme complex involved in H2 production are

hydrogenase or nitrogenase. These enzymes regulate the hydrogen

production process in prokaryotes and some eukaryotic organisms including

green algae. The excess electrons generated during catabolism inside the

cells are disposed in the form of H2 by the action of hydrogenase protein.

The biohydrogen production process can be classified into two broad

group viz. light dependent and light independent process. Light mediated

processes include direct or indirect biophotolysis performed by algal species

and photo-fermentation performed by purple non-sulphur bacteria. Dark

fermentation is performed by heterotrophic organotrophic microbes. The algae

use their photo-synthetic apparatus and solar energy to convert water into

chemical energy. In this process, oxygen is produced as by-product. This

oxygen acts as inhibitor of enzyme system responsible for hydrogen

production.

The coupling of two separate stages of micro-algal metabolism i.e

photosynthesis and fermentation for hydrogen production is termed as indirect

‘bio-photolysis'. The fixation of CO2 into storage carbohydrates (e.g. starch in

green algae, glycogen in cyanobacteria) is coupled with fermentation of these

stored energy reserve for H2 production under anaerobic conditions. This

process is not marred with the problem of oxygen accumulation. Thus it is

considered more efficient than direct photolysis of water. To compete with

alternatives sources of renewable H2 production process, such as photovoltaic

electrolysis, the bio-photolysis processes must achieve close to an overall

10% solar energy conversion efficiency. To achieve high solar conversion

efficiencies, certain biotechnological steps are required. One of such steps

could be reduction of number of light harvesting pigments or use of

metabolically engineered cell that are more efficient in fermentation of stored

carbohydrates to H2.Improvement of bioprocess parameters could lead to the

solution of scaled up operation of photo bioreactor for hydrogen production.

Among all the biological H2 production processes, dark fermentation

shows highest H2 production rates. This process holds promise for

commercialization. If evolution of microbes is considered, as the availability of

98

organic matter on earth varied, the fermentative microbes capable of H2

production i.e. fermentative bacteria evolved with the appearance of organic

material on earth. These microbes adapted themselves to different growth

conditions (mesophilic temperatures, thermophilic temperatures, etc.) and

complexity of the substrate. They are heterotrophic in nature and produce H2

under anaerobic conditions. The metabolism of these microbes involves

utilization of simple sugars and production of electron donors in terms of

NADH. The substrate-level phosphorylation is the only way of ATP production

under anaerobic conditions. The NADH thus produced is used by Fe-Fe

H2ase enzyme complex to produce molecular hydrogen in obligate

anaerobes. In case of facultative anaerobes, the format lyase enzyme breaks

format to molecular hydrogen and carbon dioxide. Format lyase is also known

as Ni-Fe hydrogenase whose turnover number is lower than Fe-Fe H2ase.

Thus obligate anaerobes are reported as highest H2 producing organisms.

Theoretical maximum yield for hydrogen production is 4 moles / mole of

glucose. Fermentative microbes growing at thermophilic temperatures are

reported to produce hydrogen at high rate. There are many advantages of

thermophilic bioH2 production viz. at thermophilic temperature the

thermodynamics of H2 production is more favorable. Moreover, temperatures

greater than 600C lead to pathogen destruction and reduce the chances of

unwanted contaminations. Very few end-metabolites are produced under

thermophilic regime. These end-metabolites are generally composed of

ethanol, acetate, butyrate, propionate, etc. The presence of these molecules

in the spent media leads to extra burden of waste disposal.

The photoheterotrophic process converts the volatile fatty acid rich

spent media of dark fermentation to hydrogen. Photo-fermentative bacteria

such as Rhodopseudomonas, Rhodobactersp, Rhodospirullum sp., etc. are

the major photo-fermentative bacteria. Light intensity, light wavelength and

illumination protocol are the major factors that drive the photo-fermentation.

Theoretically, H2 production from 1 mole of acetate, propionate and butyrate

are 4, 7 and 10 moles, respectively. Thus integration of photo-fermentation

with dark fermentation was considered for the maximization of gaseous

energy recovery (Figure 5.1). But there were many operational challenges of

using photo-fermentative bacteria. One of the major problems faced was the

light shading effect generated by accumulation of pigment in the photo-

fermentative microbes. Moreover, the rate of H2 production was also

considerably low when compared with dark fermentation. Photo-bioreactor

design and scale up challenges have hampered the implementation of

integration of photo-fermentation with dark fermentation. Poor light conversion

efficiency of these organisms and requirement of external light source made

this process energy intensive.

99

Another two-stage process where bioH2 production process was

integrated with bio-methanation was also considered as a feasible option of

improvement of gaseous energy recovery. Since bio-methanation process is a

well-established process, the implementation of such integrated process holds

a lot of promise. Scaling up of biomethantion process is relatively easy and

less costly. Thus the mixture of bio-hydrogen and bio-methane can be

collectively called under the eponym of “HyMet”.

Figure 5.1 Gaseous Energy Recovery in Two-stage Integrated Process.

5.2 International status: First review on bio-hydrogen production was

published in Nature Biotechnology as “Bio-hydrogen production deserves

serious funding”. Subsequently, impetus on bio-hydrogen gained momentum

in early 21st century. Major contributors in bio-hydrogen production research

were from United States of America, Canada, Malaysia, Indonesia, Thailand,

China and India. National Renewable Energy Laboratory (NREL), Oak Ridge

USA, funded initial bio-hydrogen studies in USA. Enzymatic bio-hydrogen

production and bio-hydrogen from waste paper was the major initiative taken

by NREL. Different microbes were discovered in different parts of the world,

each having unique hydrogen production ability. Potential of E. coli in bio-

hydrogen production and its metabolic engineering was explored by

100

Hellenbeck in the year 2006. Many mesophilic species were explored for

hydrogen production. Enterobacteraerogenes was one of the commonly

studied facultative anaerobes. Obligate hydrogen producing microbes were

popular species due to their higher H2 yields. Thermophilic bio-hydrogen

research gained importance by 2004. ThermophilicClostridium thermolacticum

was reported for the first time for bio-hydrogen production. Pusan National

University, Pusan, South Korea studied Thermophilic H2 production from

glucose at 55-64oC using a continuous trickling biofilter reactor (TBR) packed

with a fibrous support matrix. The biogas composition was around 53 % of H2

and 47 +/- 4% of CO2 by volume. The thermophilic TBR is superior to most

suspended or immobilized reactor systems reported thus far. This is the first

report on continuous H2 production by a thermophilic TBR system. As time

passed on, need of renewable feedstock for bio-hydrogen production was

realized, as for bio-hydrogen to be considered as renewable energy source, it

should be produced from renewable raw materials only. The concept of waste

management coupled with energy generation was popularized. In 2003,

Logan et al. first reported the possibility of wastewater management along

with hydrogen production. Major surge in bio-hydrogen research was in the

year 2004. Dark fermentative H2 production using packed bed reactor was

first explored by Logan et al.in 2004. Up till now significant research has been

done on bioH2 production. Many studies were done in pilot scale units.

Internationally very few studies are available for commercial H2 production.

Integration of bio-hydrogen with fuel cell was first mooted by Marta S.

Basualdo in 2012.This concept still needs a serious consideration since this

technology can produce H2 in decentralized manner for low and medium level

electricity needs.

5.3 National Status

In India, first dedicated pilot-scale bio-hydrogen production unit using

distillery effluent was reported by Shri AMM Murugappa Chettiar Research

Centre (MCRC) using defined bacterial co-culture. MCRC has developed a

biological process for generation of hydrogen from sugar and distillery wastes

using the effluents at M/s. E.I.D. Parry Ltd., at Nellikuppam, Tamilnadu.

MCRC has been working on scaling this technology using a 125 m3 bioreactor

which has produced 18,000 liters of total gas per hour with about 60%

hydrogen mixed largely with CO2 and CO. Indian Institute of Technology

Kharagpur was one of the leading institutions involved in bio-hydrogen

research for more than a decade. IIT Kharagpur demonstrated high rate of

hydrogen production in packed bed reactor configuration in a pilot scale unit.

Its main emphasis was on utilization of organic wastes for energy generation.

Under the leadership of IIT Kharagpur an attempt for commercialization of bio-

hydrogen production was envisioned through the mission mode project

“Biohydogen through Biological Routes” sponsored by MNRE. IIT Kharagpur

101

is also involved in development of novel and cheap media composition which

would make the product cost effective. It is mainly focused on the

identification of cheap nitrogen sources that can replace the need of yeast

extract and tryptone in the fermentation media. Moreover, it is also involved in

waste to energy concept. Use of distillery effluent, starchy wastewater and

lingocellulosic biomass as substrates are receiving more attention. Other

collaborators in this group include institutions with varied experiences in bio-

hydrogen production. Indian Institute of Chemical Technology, Hyderabad has

developed rapid screening methodology for selecting organic waste for bio-

hydrogen production. Jawaharlal Nehru Technological Institute, Hyderabad

has developed mixed consortia from mangroves sludge and hot spring for

hydrogen production. The Tata Energy Research Institute (TERI), New Delhi

has a well-established large scale bioreactor facility for bio-hydrogen

production. It is involved in thermophilic H2 production process. Banaras

Hindu University and Allahabad University were chosen for photo-

fermentation studies.

Under a Mission Mode Project on Biological Hydrogen Production

sanctioned by MNRE in 2009, two 10 m3 capacity reactors are under

installation at IIT Kharagpur and IICT Hyderabad using distillery effluent and

kitchen waste respectively. These bio-reactors are expected to produce 30-

50 m3 of hydrogen per day. In addition, technical document for setting up an

industrial level reactor will also be developed under this project. In

collaboration with IIT Kharagpur, Naval Material Research Laboratory

(NMRL), Mumbai has been planning to integrate bio-hydrogen with chemical

fuel cells for electricity generation. Other institutions/universities such as Anna

University, Institute of Genomics and Integrative Biology India, New Delhi, etc

are also actively involved in bio-hydrogen production.

The National Institute of Technology, Raipur recently started working

on the development of Microbial Electrolytic Cellfor economic and energy

efficient bio-hydrogen production from leafy biomass by electro-hydro-

genesis.

Indian Association for the Cultivation of Science, Kolkata is working on

the development of a bio inspired catalyst that would efficiently catalyse

hydrogen evolution and give better understanding about the mechanism of the

hydrogen evolution reaction (HER) by the [Fe-Fe]- Hydrogenase enzymes

which will in turn be helpful in the development of better HER catalyst in terms

of performance and turnovers. Novel hydrogenase model complexes

(catalysts) have been synthesized with a clickable alkyne group. For robust

and successful immobilization of the catalyst onto the electrode surface, the

graphene oxide is modified with aza-amine with azide group to get aza

terminated ITO supported graphene as electrode material and the alkyne end

102

of the catalyst is clicked onto electrode with Cu(I) as the catalyst. The

catalysts so developed will be used for production of H2 from H2O.

5.4 Action Plan and Suggestions

Hydrogen production through dark fermentation has certain limitations.

Gaseous energy recovery in terms of only H2 might not be sufficient to make

this process commercially viable. Only 20 to 30 % of total energy can be

recovered through H2 production. Even though integration with photo-

fermentation, theoretically, 12 moles of H2 /mole of glucose can be recovered

but due to scaling up problem of photo-fermentation such a two-stage process

is difficult to commercialise. To make the dark fermentative hydrogen

production worthy of commercialisation, it should be integrated with the bio-

methantion process. The spent media of the dark fermentation is rich in

volatile fatty acids that would be an ideal substrate for methanogens. Bio-

methantion technologies are well established and are easy to scale up. The

integration of these two processes might lead to 50-60% gaseous energy

recovery (Figure 5.2). Most attractive point of such a process is that the

reactor used for H2 production could be used for bio-methanation. So,

separate reactor is not required. This would lead to decrease in operational

cost of the entire process. Bio-hymet production could be envisioned as

renewable source of energy only when it would be produced from renewable

sources. Any organic compound which is rich in carbohydrates, fats and

proteins could be considered as possible substrate for bio-hymet production.

The advent of technology, such as fuel cell that converts hydrogen to

electricity has infused new life to the implementation of hydrogen based

economy. The path of hydrogen economy would be realized through the

implementation of fuel cell system with the bio-hydrogen production systems.

The efficient fuel cells, that would be able to perform at ambient temperatures

and would require minimum maintenance, are the major advantages towards

their commercialization. Till now very few steps have been taken on

demonstration of integration of bio-hydrogen production with fuel cells. It

would be interesting to see the performance of continuous bio-hydrogen

production when connected to fuel cells.

The bio-hydrogen setup should be put strategically near to those

places where supply of feedstock is cheap and easily available. The electricity

generated by such process could be helpful for rural electrification.

Development of such process would lead to decentralized use of hydrogen.

103

Figure 5.2 Bio-hymet Concept for Maximum Gaseous Energy Recovery

International and National status and gaps of technologies of bio-

hydrogen production routes have been compared in Table 5.1.

Table 5.1 Comparison of Bio-hydrogen Production Routes

Techno

logy

International

Status

National

status

Technology

Gaps

Suggestions

Direct

Biophotolysis

Techno-

logical

advancement

was not

encouraged

Techno-

logical

advancemen

t was not

encourage

Expensive and

difficulty in

scaling up of

photo-

bioreactor,

inhibition of H2

production

due to oxygen

toxicity,

H2 production

rate are not

encouraging

Development of

mutant strains

resistant to O2

toxicity,

Development of

cheap material of

construction for

photobioreactors

104

Indirect

Biophotolysis

Technological

advancement

was not

encouraged

Technologic

al

advancemen

t was not

encourage

Expensive and

difficulty in

scaling up of

photobioreact

ors,

H2 production

rate are not

encouraging

Development of

strains that are

more efficient in

starch

accumulation

and

fermentation,

Development of

cheap material of

construction for

photobioreactors

Photo-

fermentation

Scale up pilot

plant of 100 L

was

developed

Lab scale

stage

Expensive and

difficulty in

scaling up of

photobioreact

ors,

Shading effect

of pigments

produced by

the microbes,

poor

photosynthetic

efficiency,

H2 production

rate are not

encouraging

Development of

mutant strains

having low

pigment content,

heterologous

over expression

of

clostridialH2ase,

Development of

cheap material of

construction for

photobioreactors

Dark

fermentation

Pre

commercial

stage

Pre

commercial

stage

Scale up

problem,

development

of large scale

bioreactors,

screening of

potential

microbes, raw

material

availability,

Storage of H2,

Purity of H2

produced is

not sufficient

to be supplied

to fuel cells

Use of

customized

packed bed

reactor systems

for high rate of

H2 production,

Use of organic

industrial and

household waste

as feedstock,

Development of

cheap gas

scrubbing

technologies

such as water

scrubbing

105

HYDROGEN PRODUCTION THROUGH

THERMOCHEMICAL ROUTES

106

107

6.0 Hydrogen Production through Thermo-chemical Route

6.1 Introduction

Thermo-chemical splitting of water to produce hydrogen was

considered as one of the potential methods which can be scaled up for large

scale generation. In this context to provide quality heat for the process use of

energy sources such as nuclear and solar etc., was considered, as these

sources were being envisaged by these sources for input heat were

attracting worldwide attention. With regard to the choice of likely process

routes for development the iodine-sulfur (I-S) and copper-chlorine (Cu-Cl)

cycles were considered having potential for scale up hydrogen generation,

however, the process was complex and required multi-disciplinary approach

to develop suitable technology. Currently globally, these cycles are at different

stages of development and are yet to be commercially proven.

The iodine-sulfur (I-S) cycle is one of the most promising and efficient

thermo-chemical water splitting technologies for the massive production of

hydrogen. As competing processes, other options such as HTSE, hybrid

sulfur cycle and Cu-Cl cycle are also being studied for the production of

hydrogen.

Schematic of thermo-chemical water splitting cycle is shown in Figure

6.1.

Figure 6.1: Schematic of thermo-chemical water splitting cycle

Schematic and conditions of a typical Cu-Cl closed loop is shown in

Figure 6.2 and Figure 6.3.

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Figure 6.2: Schematic of a typical Cu-Cl closed loop

Figure 6.3 Schematic and conditions of a typical I-S closed loop

109

6.2 International Status

Integrated I-S loop cycle has been demonstrated in the following

countries:

Country Year

USA : 1980

European Union : NA

Canada : NA

Japan : 2004

South Korea : 2009

China : 2010

India : 2013

Country wise status and plan on I-S process is discussed below.

6.2.1 United States of America: The Nuclear Energy Research Initiative

(NERI) was established with the goal to demonstrate the commercial scale

production of hydrogen using nuclear energy by 2017. The modular helium

reactor (MHR) has been suggested as the Generation IV reference concept

for nuclear hydrogen generation on the basis of either the I-S thermo-

chemical cycle or HTSE.As part of the national hydrogen research

programme, the US DOE created the Nuclear Hydrogen Initiative (NHI) with

the objective to advance nuclear energy for the support of a future hydrogen

economy. The frame was widened with the start of the International Nuclear

Energy Research Initiative (I-NERI) for bilateral or multilateral international

cooperation supporting R&D activities for Generation IV reference concept of

the NHI and the advanced fuel cycle R&D. The objectives of I-NERI include

the development and demonstration of technologies which enable the nuclear

power based production of hydrogen by non-fossil based water splitting

hydrogen production processes. The I-S cycle development project has been

taken up by an international consortium led by General Atomics and

comprising also the Sandia National Laboratory (SNL), USA and the French

Commissariat of Atomic Energy (CEA). Between 2003 and 2008, the US

DOE promoted nuclear hydrogen programmes in the USA which concentrated

on:

- Hybrid sulphur thermo-chemical cycle development at the Savannah

River National Laboratory (SRNL);

- High temperature electrolysis development at the Idaho National

Laboratory (INL);

110

- I-S process development at the General Atomics.

Through a down selection activity led by INL and carried out in 2009to

systematically evaluate and select the best technology for deployment with

NGNP (Next Generation Nuclear Plant), the HTSE was adjudged as the most

appropriate advanced nuclear hydrogen production technology that presents

the greatest potential for successful deployment and demonstration at NGNP.

But it was also stated that both Westinghouse hybrid (HyS) and I-S processes

exhibit attractive attributes for hydrogen production, which supports not

abandoning either technology for future consideration.

6.2.2 European Union: High Temperature Thermo-chemical Cycles

(HYTHEC) was a STREP (Specific Targeted Research Project) with six

partners starting in 2004 and running over almost four years. Its main

objective was to evaluate the potential of thermo-chemical processes,

focusing on the I-S cycle to be compared with the HyS cycle.

Nuclear and solar were considered as the primary energy sources, with

a maximum temperature of the process limited to 950°C. A preliminary

reference sheet of the I-S cycle has been conceptualized and optimized to a

‘reference’ flow sheet by coupling to a single 600 MW indirect cycle Very-

High-Temperature Reactor (VHTR). The reactor, fully dedicated to hydrogen

production, is designed as a ‘self-sustaining concept” delivering both

electricity to meet the plant’s own total power demand and heat to run the

Hydrogen production process at a rate of 110 t/d and an overall plant

efficiency of ~35%.

A preliminary evaluation of the hydrogen production costs based on

solar, nuclear and hybrid operation led to following results: small plants are

powered most favorably by solar energy, while nuclear plants are most

economical at high power levels (> 300 MW(th)); hybrid systems may have

their niche in the midrange of 100 to 300 MW(th).

The 2015 targets defined for high temperature thermo–electrical–

chemical processes with solar–nuclear heat sources are reduction of CO2

emissions for fossil reforming by more than 25% and hydrogen production

cost of less than €2/kg

HycycleS is a new European project that started in 2008 involving nine

European and four associated international partners. Following in the

footsteps of the HYTHEC project, the three year project HycycleS (2008–

2010) was aimed at the qualification of ceramic materials and reliability of

components for the essential reactions in thermo-chemical cycles. The focus

was on the decomposition of sulphuric acid as the central step of the hybrid-

sulphur (HyS) cycle and the I-S cycle.

111

The final aim was to bring thermochemical water splitting closer to

realization by improving the efficiency, stability, practicability and economic

viability.

6.2.3 Canada: In close cooperation with the Argonne National Laboratory

(ANL) in the USA and the University of Ontario, Institute of Technology (UOIT)

and other universities, Atomic Energy of Canada Limited (AECL) is

investigating the copper–chlorine family of thermo-chemical cycles with

maximum temperatures that can be provided by the CANDU Mark 2 SCWR

(Super Critical Water Reactor). But apart from this cycle, AECL research

includes investigating the use of direct resistive heating of catalysts for SO3

decomposition in the I-S process.

6.2.4 Japan: In recent years, JAEA has undertaken extensive R&D on the

thermo-chemical cycles based on the UT-3 and I-S processes for H2

production. It is most advanced in the study of the I-S cycle, with the

successful operation of a bench-scale facility having achieved a hydrogen

production rate of 30 NL/h in continuous closed cycle operation over one

week. This process is now considered the prime candidate for the

demonstration of nuclear assisted hydrogen generation.

The next step, which started in 2005, is the design and construction of

a pilot plant with a production rate of 30 Nm3/h of H2 under the simulated

conditions of a nuclear reactor. While the efficiency was ~10% for the bench-

scale plant, the goal for the pilot plant is ~40%.

As a backup hydrogen production method, the high temperature

electrolysis has also been investigated, but has not yet gone beyond lab-scale

testing (Figure 6.4)

Figure 6.4: Plan of proposed R&D activities

6.2.5 South Korea: The projected hydrogen economy in the Republic of

Korea requires that 25 % of total hydrogen be supplied by advanced nuclear

112

reactors by 2040. This amount of hydrogen is around 3 Mt/year and it is

expected to be produced in 50 nuclear hydrogen units. The nuclear policy in

Korea is led by its Atomic Energy Commission (AEC) which collaborates with

the Korean Institute of Energy Research (KIER), Korean Atomic Energy

Research Institute (KAERI), and the Korean Institute of Science and

Technology (KIST).

Korea launched its nuclear hydrogen program in 2004 with two targets

as under:

(1) Generation of hydrogen for fuel cell applications such as electricity

generation, passenger vehicles, and residential power and heating,

and

(2) Lowering hydrogen costs and improving efficiency of the related

processes.

The following nuclear hydrogen programs were approved by AEC:

NHDD—“Nuclear Hydrogen Development and Demonstration” program

which started after 2011 and go up to 2030

(Milestones: 2022—prototype construction, 2026—technology

demonstration, 2030—technology commercialization).

Hydrogen production program with two phases:

– I: Hydrogen production from natural gas, petroleum naphtha, and

electricity (ending in 2025)

– II: Hydrogen production from coal, nuclear energy and renewable

energy (ending in 2040)

For the reference case design of the VHTR-H2 system, an underground

VHTR reactor of 200 MW thermal output will be coupled with an I-S

cycle to generate hydrogen from water

I-S cycle development. It runs in parallel with NHDD (Nuclear

Hydrogen Development and Demonstration) and GIF (Generation IV

International Forum) programs and it has two phases:

– I: 2006–2011 for development of key technologies

– II: 2012–2017 for performance improvement and validation

I-NERI-Korea participates in the I-NERI program of DOE with joint

projects with the Idaho Nuclear Laboratory and Argonne National Laboratory.

Korea also established two major joint research agreements, namely:

113

(1) Nuclear Hydrogen Joint Development Centre (NHDC) with General

Atomics,

(2) Nuclear Hydrogen Joint Research Centre with China (via INET).

6.2.6 China: R&D on hydrogen production through water splitting using

HTGR as a process heat source was initiated in 2005 as one component of

China’s HTR-PM (High Temperature Reactor – Pebble Module)

demonstration project. Both the I-S thermo-chemical cycle and high

temperature steam electrolysis have been selected as potential processes for

nuclear hydrogen production.

Beginning with preliminary studies, the R&D programme, now part of

the HTR-PM project, will be conducted in phases as under:

– Phase one (2005–2009): verification of nuclear hydrogen production;

– Phase two (2010–2012): bench-scale testing;

– Phase three (2013–2020): pilot-scale testing, R&D on coupling

technology with reactor, nuclear hydrogen safety;

– Phase four (after 2020): commercialization of nuclear hydrogen

production.

Other countries such as Italy, South Africa and France are also working

on different thermo-chemical cycles including I-S and Cu-Cl processes.

6.3 National Status

6.3.1 Work Done by Bhabha Atomic Research Centre

R & D for the Production of Hydrogen by Splitting Water using

nuclear Heat: Successful feasibility demonstration of cyclic operation of the

process provided fillip to intensify the development effort for tackling variety of

issues like efficient integrated process schemes, equipment, materials and

analytical techniques etc. Efforts are also on to demonstrate the operation

under prototypical conditions to generate data for assessing the viability of the

process for large scale deployment.

The road map for I-S process development is shown in Figure 6.5.

114

Figure 6.5: Road Map for I-S Process

High temperature reactor based iodine-sulfur (I-S) thermo-chemical

cycle offers a promising approach to the high efficiency production of large

volumes of hydrogen from water.

The I-S cycle consists of three sections as expressed in following

equations:

SO2 + I2 + 2H2O = 2HI + H2SO4 (25 – 120oC) -------- (i)

H2SO4 = H2O + SO2 + 0.5O2 (800 – 900 oC) -------- (ii)

2HI = H2 + I2 (350-450 o C) --------- (iii)

Pilot Scale Demonstration

13 M3

H2/Hr

Bench Scale Demonstration

150 Lit H2/Hr

Demonstration with 600 MWth

HTR

80,000 M3

H2/Hr

Experimental

Validation

Material Studies

Design and

Simulation

Research

and Development

115

The Equation (i) is the Bunsen reaction where water is split by sulphur-

dioxide (SO2) & iodine (I2) at relatively low temperature. Equation (ii) is the

highest temperature reaction of the cycle where high temperature is achieved

using Nuclear (High Temperature Reactors) / Solar heat. Equation (iii) is

hydrogen iodide (HI) decomposition reaction, where HI is decomposed into

hydrogen (H2) & iodine by heating at intermediate temperatures. The I-S

process is a closed loop process as the chemicals SO2 & I2 are recycled back

to the system, water & heat are the only input and the output is hydrogen (H2)

as product and oxygen (O2) as the by-product.

Initially Bunsen reaction studies were carried out at Chemical

Technology Division of BARC to study the overall reaction kinetics. A sketch

of the apparatus used in the experiments of SO2 chemical absorption in water

containing iodine is shown in Figure 6.6.

Figure 6.6: Schematic of Bunsen Reactor Setup

The experimental results for the SO2 absorption into aqueous solution

containing iodine are shown in Figures 6.7 & 6.8.

116

Figure 6.7: SO2 Inlet Partial Pressure Vs Absorption Rate

117

Figure 6.8: Batch Time (Experimental) Vs Batch Time (Calculated)

The other reactions of I-S process require catalyst. In house catalysts are

developed and tested in BARC. Chemistry Division, BARC has developed

catalyst for sulfuric acid decomposition and Heavy Water Division, BARC has

developed catalyst for HI decomposition reaction. The test facility and

characterization is shown in the Figure 6.9& 6.10.

118

Figure 6.9: HI Decomposition Test Facility and Catalyst Characterization

Figure 6.10: Catalyst Characterization for Sulfuric Acid Section

HI Catalyst Characterized and tested at 350°C

Catalysttemperature

HI decomposition fraction

423 K%

523 K 3 %

623 K 14 %

0.4

Cr0.2Fe1.8O3 more

active than Fe2O3

SO2 yield: as a function of acid flux

Fresh catalyst

Used catalyst

119

As a first step to demonstrate the I-S process and feasibility of closing

the loop, Chemical Technology Division, BARC has initiated the efforts for the

same. The I-S closed loop system has been worked out in glass/quartz

equipment, operating at atmospheric pressure and prototypical temperature

conditions.

Figure 6.11: Layout of Closed Loop Figure 6.12: Boxed up Arrangement

Glass System (CLGS) for CLGS.

The closed loop glass setup (Figure 6.11 and Figure 6.12) is divided into 3

sections as given below:

1. Bunsen Section

a. Bunsen Reaction

b. Liquid-Liquid Separation

c. Acid Purification

2. Sulfuric Acid Section

a. Sulfuric Acid Concentration

b. Sulfuric Acid Decomposition

3. HI Section

a. HIx Distillation

b. HI Decomposition and HI Recovery

c. Hydrogen Purification

The pictures of various equipment/systems during operation are given in

Figures 6.13 to 6.17.

120

Figure 6.13: Bunsen Reactor during Operation & Liquid- Liquid Phase

Separation

Interface of two phases

121

Figure:6.14 SO3 Decomposition Experiment

Figure 6.15: HIx Distillation Equipment

122

Fig 6.16: Sulfuric Acid Concentrator and Decomposer

Fig 6.17: HI Decomposition System

The closed loop glass system is operated continuously for a period of

20 hours at the hydrogen production rate of 30 lph. India is the 5th country in

123

the world to achieve I-S closed loop operation in glass system, after USA,

Japan, China and South Korea. The Chemical Technology Division, BARC is

also pursuing the studies on Bunsen reaction and phase separation at high

pressures in Metallic Bunsen System (MBS) and sulfuric acid decomposition

studies in High Pressure Sulfuric acid Decomposition System (HSDS). This

will give substantial inputs for the closed loop metallic system at higher

pressures (Figure 6.18 and Figure 6.19).

Figure 6.18: Reactor & Separation System

124

Figure 6.19: Feed System

Schematic of Operations Envisaged in Integrated Reactor of HSDSis

given in Figure 6.20.

125

Figure 6.20: Schematic of Operations Envisaged in Integrated Reactor

of HSDS

Cut View of Integrated Reactor of HSDSis shown in Figure 6.21.

126

Figure 6. 21: Cut View of Integrated Reactor of HSDS

Heavy Water Division, BARC is working on reactive distillation route to

produce hydrogen by splitting of HI acid. Desalination Division, BARC is

working on alternate route for HI decomposition section studies using electro-

electro dialysis for concentration and membrane reactor for decomposition of

HI to produce hydrogen.Alumina Supported Silica Membraneis shown in

Figure 6.22.

Figure 6.22: Alumina Supported Silica Membrane

Membrane Reactor for HI Decomposition is shown in Figure 6.23.

127

Figure 6.23: Membrane Reactor for HI Decomposition

Chemical Technology Division, BARC has taken the initiative to carry

out the I-S process demonstration in engineering material of construction. For

that purpose Atmospheric Metallic Closed Loop (AMCL) is being taken up by

the division. The P&ID is ready for the setup. Process designing for the setup

is underway.

The Chemical Engineering Division, BARC has started working on 3-

step Copper Chlorine (Cu-Cl) process. The Chemistry Division, BARC along

with Chemical Technology Division, BARC have started working on Hybrid

Sulfur (Hy-S) process.

6.3.2 Work Done by ONGC Energy Centre

ONGCEnergy Centre (OEC) is working on sections of I-S process

through IIT-Delhi, CECRI Karaikudi. ONGC is working on Cu-Cl process

through ICT-Mumbai. They have demonstrated proof of principle experiments

and are going ahead with design to demonstrate 25 NL/h Hydrogen

production capacity lab-scale unit. OEC started several sub-projects in

collaboration with some of the leading research institutions for research on the

initial proof of principle process development, which were to be followed up by

further development work to scale up the process.

128

In case of Cu-Cl cycle, the originally proposed five step cycle by

Argonne National Laboratories, USA has been modified and established.

Several novel designs especially in electrochemical section were made to

improve the system. The energy calculations showed that there is no

additional energy requirement in the modified cycle as compared to originally

reported ANL cycle and also reconfirmed that it is a non-catalytic process.

Efforts made to cross-confirm the data generated in electrochemical cell

parameters generated in the studies at ICT, Mumbai confirmed further that the

data is in the range reported in a parallel project study undertaken at CECRI,

Karaikudi.

Based on proof of concept studies, a conceptual closed-loop Cu-Cl

process for hydrogen generation@ 25L/h was developed to design and

fabricate a metallic lab-scale engineering process facility with indigenous

sources. A model metallic reactor fabricated initially helped freezing the

design and fabrication of hydrogen generation, CuCl2 hydrolysis,

decomposition and oxygen generation reactors. This approach has resulted in

considerable time and cost saving in the project besides instilling confidence

in indigenous capability development. A spray drier system was designed and

fabricated for drying CuCl2 to produce very fine and pure CuCl2 powder. The

electrochemical set up required in the integrated closed-loop operation was

developed using the data generated through series of electrochemical cells of

varying capacities viz., 2A, 5A, 12A finally leading to design/fabrication of 60

A stack with improved designs and indigenous fabrications using

commercially available materials viz., electrodes, membranes, cell materials

etc. During the studies, a novel method was developed for complete

conversion of CuCl after electrolysis reaction based on which a suitable

process gadget was designed to enable trouble free closed-loop operation of

the cycle.

In the integrated facility indigenously developed for closed-loop

operation all reactors viz., hydrogen, oxygen generation, CuCl2-hydrolysis and

decomposition along with electrochemical system were individually checked

for their performance and found to be working as per desired specifications.

Several facilities required for transfer of solids between individual units were

developed with a newly designed and fabricated flexible screw conveyor

along with provision for liquid transportation between various units across the

loop.

The engineering scale process plant, now installed at ICT, Mumbai is

proposed to be shifted to OEC project site in Panvel.

129

In the I-S cycle, electrochemical Bunsen reaction and electro dialysis

technique for HI enrichment were established at lab-scale with minimum

cross-contamination levels across membrane and without any side reactions.

Model codes were developed in simulation work undertaken to address

scaling up and issues related to integration with the remaining sections of the

cycle. In H2SO4 decomposition section of this cycle, a cost-effective, high

performing and highly stable non-Pt-based catalyst system was developed

and tested in an in-house designed, fabricated pilot scale metallic reactor

system equivalent to 150 L/h of H2 generation. Performance of selected

catalyst system under lab stage was evaluated further in this reactor at

900±50°C and 10-15 bars and found to be highly satisfactory. Mechanistic

studies on catalytic decomposition of H2SO4were completed. In HI

decomposition section, a highly performing transition metal based catalyst

system was developed that yields conversion being close to equilibrium

values at 500-550°C. The catalysts were stable for over 100 hrs. Through a

short study techno-economic feasibility of open loop I-S cycle was also

evaluated.

The research work performed by OEC and the collaborating

institutions have thus been able to successfully establish the proof of concept

for developing both Cu-Cl and I-S cycles and has led to setting up metallic

closed loop lab scale engineering facility in Cu-Cl cycle. These

accomplishments are major steps in technology development for these two

processes and achieved for the first time in the country.

ONGC Energy Centre has been able to successfully develop the

indigenous process, several process equipment and trained manpower in the

country. The collaborative R&D on both cycles has resulted in

publications/presentations of 46 technical papers in national / international

conferences and Journals. The research work has also resulted in filing of 7

Indian patents. In addition, keeping in view the recent international

developments in research in Cu-Cl cycle, which is considered most potential

for scale up, OEC has filed 3 international patents related to Cu-Cl cycle in six

countries (UK, USA, Canada, Japan, Korea and China). In the last few

months USA and Japan have accepted our patent application on multi-step

Cu-Cl cycle and patent has been granted in these two countries.

Scheme of R&D activities related to I-S cycle at OEC, Mumbai is given

in Figure 6.24.

130

Figure 6.24 Scheme of R&D activities related to I-S cycle at OEC, Mumbai

6.3.3 Highlights of the R&D Work

The OEC had planned to implement the project work in two distinct

stages viz., establish the proof of concept, followed by the lab-scale

development in association with collaborative research group for the

selected process route and thereafter, setting up of the pilot plant at OEC

premises at appropriate time to transform the developed knowledge and

expertise to further scale up. In this context, a total of 16 collaborative sub-

projects and 1 in-house project were undertaken as per details given below:

8 sub-projects to establish proof of principle of both the Cu-Cl and I-S

cycles

131

3 sub-projects to establish alternate paths for these cycles

1 sub-project to establish closed-loop operation of Cu-Cl cycle

1 sub-project to establish techno-economic feasibility of open-loop

cycle

3 sub-projects to addresses various issues related to simulations /

modeling, scale up / bridging the gaps for achieving closed loop

operations

1 In-house sub-project on simulation of I-S and Cu-Cl Cycle

The details of various collaborative sub-projects / in-house projects

undertaken in line with the scope of the work are given in Table 6.1:

Table 6.1 List of Collaborative Sub- projects in I-S and Cu-Cl Cycles

1 Proof of Principle of Cu-Cl Cycle (3 Sub-projects)

Sl.

No

Title of the Project

Duration / Start

Date / End Date

Institute Amount

committed

(Rs Lakh)

Amount

Released

(Rs Lakh)

Status

1.1 Preliminary process

analysis for copper-

chlorine (Cu-Cl)

thermochemical

hydrogen

production process

42 months /

01.07.07 /

31.12.10

ICT,

Mumbai

80.40 80.40 Completed

1.2 Experimental data

collection on

oxidation of CuCl

and recovery of Cu

10 months /

28.04.08 / 28.02.09

CECRI,

Karaikudi

6.23 6.23 Completed

1.3 Studies on the

electrolysis of CuCl

& recovery of Cu –

Energy

Optimisation –

Phase II

9 months / 27.02.10

CECRI,

Karaikudi

10.70 10.70 Completed

132

/ 26.11.10

Sub Total-1 97.33 97.33

2 Proof of Principle of I-S Cycle (5 Sub-projects)

2.1 Studies on the

catalytic

decomposition of

Sulfuric acid in the

I-S process for

Hydrogen

production

57 months /

11.01.08 / 11.10.12

IIT-Delhi 107.74 107.74 Completed

2.2 Studies on Bunsen

reactor for

production of

sulfuric acid and HI

using

electrochemical

cell48 months /

21.01.08 / 21.01.12

IIT-Delhi 102.77 102.77

Completed

2.3 Concentration of

HIx Solution Using

Electroelectrodialys

is

48 months /

21.01.08 / 21.01.12

IIT-Delhi Completed

2.4 Catalytic

Decomposition of

Hydrogen Iodide

(HI) into I2 and H2

57 months /

29.09.08 / 30.06.13

IIT-Delhi 45.63 45.63 Completed

2.5 Development of

Hydrogen

Transport

Membrane

Reactors for

Hydrogen Iodide

decomposition

followed by

hydrogen removal

36 months /

29.09.08 / 28.09.11

IIT-Delhi 31.64 31.64 Completed

133

Sub Total -2 287.78 287.78

3 Simulation of I-S Cycle (1 Sub-project)

3.1 Simulation studies

on the sulphur-

iodine (I-S cycle)

closed loop

thermochemical

process for

production of

hydrogen using

suitable simulation

and application

software

24 Months /

15.12.09 /15.12.11

Dr.

Babasaheb

Ambedkar

Univ.Loner

e,

Maharashtr

a (BATU)

4.09 4.09 Completed

Sub Total -3 4.09 4.09

4 Design, Installation and Lab Scale Demonstration of Closed Loop

Operation (1 Sub-Project)

4.1 ICT – OEC Process

for Copper-Chlorine

(Cu-Cl) Thermo-

chemical Hydrogen

Production –

Phase-II

30 months /

23.02.12 / 22.08.14

ICT,

Mumbai

767.87 767.87 Completed

Sub Total -4 767.87 767.87

5 Additional Studies / Alternate paths in Cu-Cl Cycle and I-S Cycles

Cu-Cl Cycle (1 Sub-Project)

5.1

Electrolysis of CuCl

– HCl system for

the preparation of

CuCl2& H2 - A

Feasibility Study

23 months /

05.04.10 / 04.03.12

CECRI,

Karaikudi

25.91 25.91 Completed

Sub Total -5 25.91 25.91

I-S Cycle (2 Sub-Projects)

5.2 Experimental

Studies for

Reaction of Metals

with HI 1.5 months

ICT,

Mumbai

2.20 2.20 Completed

134

/ 10.01.11 /

23.02.11

5.3 Experimental

Studies for

Reaction of Metals

with Hydroid Acid

&Detailed Studies

on Decomposition

of Certain

Transition Metal

Iodides

5 months /

14.09.11 / 13.02.12

ICT,

Mumbai

9.85 9.85 Completed

Sub Total -6 12.05 12.05

Techno-economical Studies on Partially Open-loop I-S Cycle (1 Sub-

project)

5.4 Techno Economic

Feasibility of Open

Loop Thermo-

chemical S–I cycle

of H2S split for

Carbon-Free

Hydrogen

Production in

Petroleum Refinery

4 months / 10.01.12

/ 09.05.12

CSIR-IIP,

Dehradun

13.47 13.47 Completed

Sub Total -7 13.47 13.47

Additional studies to address scaling up issues in I-S Cycle (2 Sub-

projects)

5.5 Modeling of

Membrane

Electrolysis Cell for

Bunsen Reaction

and Electro-

Electrodialysis Unit

for concentration of

Hix Solution

9 Months / 08.02.13

/ 07.11.13

IIT, Delhi 10.86 7.61 Completed

135

5.6 Mechanistic

Studies on the

Catalytic

Decomposition of

Sulfuric Acid in the

I-S Cycle for

Hydrogen

Production

12 months /

25.02.13 /

24.02.14

IIT, Delhi 17.48 11.19 Completed

Sub Total -8 28.34 18.80

Grand Total (Sub

Total 1-8)

1236.84 1236.84

6.0 Simulation Studies

on Thermochemical

Iodine-Sulfur&

Copper-Chlorine

Cycle for Hydrogen

Production

5 Years / May

2010 – Sept. 2015)

OEC

(In-house)

- - Completed

The linkage between various sub-projects is shown in Figure 6.25.

136

Figure 6.25 Linkage between various sub-projects

6.3.4 Highlights of the R&D Work

(i) Cu-Cl Cycle

The proof of principle experiments for all reactions of Cu-Cl cycle have

been successfully completed, using a combination of thermo-chemical

and electrochemical routes. This has resulted in development of a ICT-

OEC modified and patented Cu-Cl cycle.

In modified cycle; hydrolysis step was suitably modified to overcome

problems faced in formation and characterization of copper

oxychloride.

Detailed thermo-chemical calculations of the modified route indicated

that there is no excess heat demand in the modified route.

Analytical test methods and procedures to facilitate trouble free

operations during closed-loop operations have been standardized

In the electrochemical reaction, based on a novel cell design 2A cell

has been fabricated. It resulted in low cell voltage of 0.7 ± 0.1V along

137

with >90% current efficiency, 5-10μ particle size of copper generated in

the process under operating conditions that could be directly used as

feed / reactant in the Cu-HCl-Hydrogen generation reaction.

Kinetic studies for all reaction steps of the Cu-Cl cycle have been

performed and from the activation energy value it has been confirmed

that this is a non-catalytic reaction process.

Based on the experimental data generated in the proof of principle

experiments, a basic flow sheet has been initially developed for the

closed-loop experiment to generate hydrogen @ 2.73 liters per hour

(lph), subsequently revised to 5 L/h and finally to @ 25 L/h to align

with market supply of various process gadgets.

Detailed studies on flow simulations, cold flow experiments etc., have

been performed to finalize the reactor configuration.

A 5 Ampere electrochemical cell has been fabricated. The

performance of the cell showed that cathodic current density of

133mA/cm2 at a cell voltage of 0.7 ± 0.1 V.

Further scale up to a 12A electrochemical system was done with

improved design. A cathodic current density of 187 mA/cm2 at 0.7 ±

0.1V could be achieved.

Aerial oxidation of CuCl solutions has been found to be a major issue in

electrochemical step. A novel method has been developed for

complete conversion of CuCl after electrolysis reaction. Accordingly a

suitable process gadget has been designed and fabricated for onsite

application during closed-loop operation.

Based on the outcome of electrochemical studies, a 60A stack has

been developed to integrate with thermal reactors.

Initially a representative metallic model reactor system for hydrogen

generation @ 25 L/h has been designed and fabricated to study all

thermal reactions based on which design /fabrication of all the other

reactors viz., hydrolysis, decomposition and oxygen generation

reactors has been taken up. This approach has helped in reducing the

cost and meeting the project time line.

Hydrogen generation @ 27 L/h in the hydrogen generation reactor has

been achieved under specified operating conditions.

Hydrolysis reactor has been operated at 450°C and the reactor is

behaving ideally. When the oxygen generation reactor was run at

500°C; the experimental data indicated oxygen production @ 13.7 L/h.

CuCl2 decomposition reactor has yielded fine CuO powder and Cl2 gas

at 475oC.

138

Experimental runs on commissioned spray drier system have been

performed for drying CuCl2 at 140°C and the units have delivered

desired results. Data generated on the dryer unit have resulted in

encouraging results in which very fine and pure CuCl2 powder has

been obtained as confirmed by UV-Visible spectroscopy, iodometric

and titrimetric methods.

Simulations / Modeling studies in Cu-Cl cycle have been performed on

Aspen Plus simulator. Flow sheets for individual sections/ process

leading to integrated system / process have been developed. Energy

balance and mass balance has been calculated and compared with

theoretical values.

Proof of principle of alternate electrochemical reaction pathway has

been established at CECRI, Karaikudi. The studies have shown that

100% efficiency at low cell voltage (0.8V) and 250A/m2 current density

at 80°C under ambient pressure conditions could be achieved. Based

on lab studies, a 25A scale electrochemical cell has been designed to

work under specified operating conditions. The study has enabled

further modification in Cu-Cl cycle in reducing number of steps/

processes.

Solid handling problems in various sections for transfer of solid copper

and copper oxide between individual units have been achieved with a

newly fabricated flexible screw conveyor based on a novel ICT- design.

Provision for liquid transportation between various units across the

loop. Facility for Integration of various individual reactors leading to

form a closed-loop has been completed.

The details the reactions in ICT-OEC route of Cu-Cl cycle is given in

Table 6.2:

Table 6.2: The ICT-OEC route of Cu-Cl cycle

S. No. Reactions ICT-OEC route : Cu-Cl Cycle

1 Hydrogen Generation 2Cu(s) + 2HCl(g) → 2CuCl(l) + H2(g)

2 Electrochemical 4CuCl(l) → 2CuCl2(aq) + 2Cu(s)

3 Drying 2CuCl2(aq) → 2CuCl2(s)

4 Hydrolysis CuCl2(s)+H2O(g) → CuO(s)+ 2HCl(g)

5 Decomposition CuCl2(s) → CuCl(l)+½ Cl2(g)

6 Oxygen Generation CuO(s)+½ Cl2(g) → CuCl(l) +½ O2(g)

139

(ii) I-S Cycle

Proof of concept of complete cycle has been established using a

combination of electrochemical and thermo-chemical reactions.

Bunsen reaction has been successfully carried out at lab-scale using a

two-compartment membrane electrolysis cell consisting of graphite

electrodes and Nafion-117 membrane.

Excess iodine used could be reduced by 75% compared to direct

contact mode. The current efficiency close to 100% has been achieved

and absence of side-reactions has been confirmed

Cross-contamination has been found to be much lower than the direct

contact mode; loss of sulfate ions to HIx section (~12%) has been

noticed due to limitation on membranes.

Electro-Electro Dialysis (EED) technique has been established and

demonstrated in lab-scale to concentrate HIx solution beyond its

azeotropic concentration.

Only Nafion membranes have been found useful In electrochemical

work

Model codes for simulation work on electrochemical Bunsen and EED

sections for I-S cycle has been successfully developed to address

scale-up issues and integration with the remaining sections of the

cycle.

In H2SO4 decomposition study, a lab-scale model quartz reactor

system has been designed and assembled to screen various catalysts.

Several transition metal/metal oxide based catalysts viz., Fe2O3/Al2O3,

Fe2O3/ZrO2, CoO/Al2O3, CuO/ZrO2, Fe2O3, Cr2O3, CuFe2O4, ZnCr2O4,

FeCr2O4, NiCr2O4, CuxCr3-xO4 etc. were screened and relative

performance of some of these catalysts were determined.

Detailed kinetic and thermodynamic studies have been performed on

promising catalyst systems. Based on the studies, a cost-effective, high

performing and highly stable non-Pt-based catalyst system for catalytic

decomposition of H2SO4 has been developed.

For the decomposition of H2SO4, High Temperature-High Pressure

(HTHP) bayonet type metallic reactor for pilot scale operation

equivalent to 150 mph in terms of H2 generation was successfully

designed, fabricated & commissioned at IIT-Delhi using in-house

expertise and indigenous resources.

The proven catalyst system under lab-stage evaluation has been

further evaluated under high pressure (10-15 bars) - high temperature

(900±50°C) experimental conditions for 24hrs. Results of this study

140

have indicated encouraging trend with the conversions in the order of

~90%.

The developed catalyst has been found to be stable for longer

durations under the actual operating conditions. It is relatively cost-

effective and superior to the available products reported. Data

generated for high pressure high temperature (HP-HT) operation is

suitable for onsite application and integration in closed loop operation.

Mechanistic studies on catalytic decomposition of H2SO4 have been

completed to address scaling up issues and integrate this step with

remaining sections of the cycle.

A lab-scale model quartz reactor system has been designed and

assembled to screen various catalysts under operating conditions of HI

decomposition.

Several transition metal (Fe, Co, Ni) based catalysts and mixed metal

catalysts like Pt-Ni combinations have been synthesized and screened

over various catalyst beds viz., Alumina, Vanadia, Molybdina, Zirconia,

Activated Carbon, and SiC in the temperature range 400-550°C.

The generated data have indicated that nickel based catalysts worked

better with the conversion being close to equilibrium values (~22%) at

500-550°C.The catalyst deactivation studies performed over 100 hrs

also indicate a marginal decrease of nickel based system activity to

~20% at the end of the test.

Studies on alternate pathways in I-S cycle for HI decomposition

involving Metal – HI reaction has also been established to explore the

possibility of ease of operation by avoiding less energy efficient

distillation processes.

Techno economic feasibility of open loop thermo-chemical I-S cycle

has been successfully evaluated.

Simulation / modeling studies of I-S open/closed-loop cycle and

alternate routes have been successfully carried out using Aspen

simulator. Individual flow-sheets have been developed leading to

Integration of different sections with one another. Energy requirement

based on theoretical basis and efficiency calculations has been

performed.

Cu-Cl Cycle, I-S Cycle and I-S Cycle Open Loop for Hydrogen

Generation are compared in Table 6.3.

141

Table 6.3. Comparison of Cu-Cl Cycle, I-S Cycle and I-S Cycle Open Loop

for Hydrogen Generation

Sl.

No.

Attributes Cu-Cl Cycle I-S Cycle I-S Cycle

Open Loop

1 No. of Steps 6 Step Process

(Combination of

Electrochemical &

Thermochemical

Reactions)

3 Step Process

(Combination of

Electrochemical

&

Thermochemical

Reactions)

2 Step Process

(Combination of

Classical

Bunsen & Hi

Decomposition

of HI with

Reactive

Distillation step)

2 Establishment

of Proof of

Concept

Proof of concept

for all 6 steps

have been

established (OEC

and Collaborators)

Proof of concept

for all 3 steps

have been

established

(OEC and

Collaborators)

Collaborative

Work is in

Progress

3 Maximum

Temperature

Encountered

550°C

(O2 Generation)

900°C

(H2SO4 Section)

500°C

(Oxidation of

H2S)

4 Total Energy

Requirement

668 kJ/molH2 675 kJ/molH2 562 kJ/mol

5 MoC Relatively Lower

Temperature (Max

5500 C)

Higher

Temperature

(Max 9000 C)

Relatively Lower

Temperature

(Max 5000 C)

6 Catalyst Not catalytic

process

Catalysts

required for both

H2SO4 and HI

Decomposition

Catalysts

required for HI

Decomposition

7 Separation Solid – Liquid

Liquid – Liquid

Gases Separation

Liquid – Liquid

Separation of

complex

azeotrope

Separation by

Reactive

distillation in HI

decomposition

step

8 Membranes Imported

(Required in

electrochemical

step)

Imported

(Required for

EBR and EED

steps)

Not Required

(when Classical

Bunsen

Reaction is

followed)

9 Electrodes Required Required Not Required

142

(when Classical

Bunsen

Reaction is

followed)

10 Process

Efficiency

5 Step = 52.57%

4 steps

Nuclear Energy:

Generation IV

Supercritical

Water Cooled

Reactor (SCWR)

= 51%

Solar Energy:

Using molten salt

= 70%

3 Step = 40%

Using Reactive

distillation = 51%

(GA)

EBR & EED

(Ideal case) =

46.5%

51%

11 By-products /

Wastes

No waste as all

products are

recycled

No waste as all

products are

recycled

H2SO4 which

can be sold for

industrial use

7. Indigenous Equipment Development

Hydrogen Generation Reactor System is shown in Figure 6.26.

Figure 6.26: Hydrogen Generation Reactor System

143

12A Electrochemical Cell with perforated Pt plate as anode is shown in

Figure 6.27.

Figure 6.27: 12A Electrochemical Cell with perforated Pt plate as anode

Spray Dryer System is shown in Figure 6.28.

144

Figure 6.28 Spray Dryer System

CuCl2 Decomposition Reactor is shown in Figure 6.29 and Hydrolysis

Reactor is shown in Figure 6.30.

Drying

Chamber

(Borosilicate

glass)

Cyclones

(Borosilicate

glass)

Scrubber

(SS 316)

Control

Panel

Pump

Spray Nozzle:

Hastelloy C

Blower

145

Figure 6.29: CuCl2 Decomposition Reactor

Figure 6.30: Hydrolysis Reactor

Oxygen Generation Reactor is shown in Figure 6.31.

146

Figure 6.31: Oxygen Generation Reactor

Cu-Cl closed loop facilty is shown in Figure 6.32.

Figure 6.32:. Cu-Cl closed loop facilty

High Temperature-High Pressure Reactor for H2SO4 Decomposition is

shown in Figure 6.33.

147

Figure 6.33: High Temperature-High Pressure Reactor for H2SO4

Decomposition

H2SO4 pilot plant facility is shown in Figure 6.34.

Figure 6.34: H2SO4pilot plant facility

148

149

HYDROGEN PRODUCTION BY

PHOTO-ELECTROCHEMICAL WATER

SPLITTING

150

151

7.0 Hydrogen Production by Photo-electrochemical Water

Splitting

7.1 Introduction

The ever increasing energy demands and rapid consumption of fossil

fuels has triggered urgent need of sustainable and renewable sources of

energy. A lot of research and its commercialization have already been done in

the areas of solar photovoltaic, however, it requires storage of energy due to

its limited operation in day-time only. Hydrogen is one of the most promising

fuels due to its highest energy density (120 MJ/Kg). Environment and energy

crisis issues can be addressed if Hydrogen can be produced in a clean and

efficient manner. Steam methane reforming is most commonly used for

Hydrogen production in industries. Source for methane reforming is a fossil

fuel and moreover CO2 gas is emitted as shown in reaction 1 & 2.

CH4 + H2O → CO + 3H2 ------- (1)

CO + H2O → CO2 + H2 -------- (2)

Renewable production of Hydrogen through solar energy is essential

considering environmental issues and can also cater to the energy needs.

There are several ways of Hydrogen production through solar energy.

However water splitting is considered as the “Holy Grail” of sustainable

hydrogen economy. Water splitting phenomenon was first observed by

Researchers in Kanagawa University, Yokohamaduring1972 where TiO2

electrode was irradiated with UV light and Hydrogen was produced by

reduction reaction at cathode and oxygen is produced at anode by oxidation

reaction.

University of Notre Dame, Notre Dame, Indiana worked on

photocatalytic water splitting. Photocatalytic water splitting consists of a

powder catalyst dispersed in water or in some suitable solution. Catalyst used

in this process needs to be photoactive and should be capable of generating

necessary charge particles to activate redox reactions. Minimum bandgap

required to split water can be calculated from the relation in between Gibbs

free energy and potential as given below:

ΔG =-nFE

Where ΔG is the change in Gibbs free energy, n is number of electrons

transferred in chemical reaction, F is faraday constant and E is the bandgap.

For water splitting, ΔG = 237KJ/mol, n=2 and F=96500 C/mol. Therefore “E =

1.23V”, is the minimum potential and hence minimum bandgap of 1.23eV is

required to split water. Thermodynamic bandgap requirement for water

splitting

152

Figure 1: Thermodynamic bandgap requirement for water splitting.

Solar hydrogen production from direct photo electrochemical (PEC)

water splitting is the ultimate goal for a sustainable, renewable and clean

hydrogen economy. In PECwater splitting, hydrogen is produced from water

using sunlight and specialized semiconductors called photo electrochemical

materials, which use light energy to directly dissociate water molecules into

hydrogen and oxygen. This is a long-term technology pathway, with the

potential for low or no greenhouse gas emissions. While there are numerous

studies on solving the two main photo-electrode (PE) material issues i.e.

efficiency and stability, there is no standard photocell or photoreactor used in

the study. The main requirement for the photocell or photo-reactor is to allow

maximum light to reach the PE.

The PEC water splitting process uses semiconductor materials to

convert solar energy directly to chemical energy in the form of hydrogen. The

semiconductor materials used in the PEC process are similar to those used in

photovoltaic solar electricity generation, but for PEC applications the

semiconductor is immersed in a water-based electrolyte, where sunlight

energizes the water-splitting process. PEC reactors can be constructed in

panel form (similar to photovoltaic panels) as electrode systems or as slurry-

based particle systems, each approach with its own advantages and

challenges. To date, panel systems have been the most widely studied, owing

to the similarities with established photovoltaic panel technologies.

Photo-electrochemical process consists of an electrode of

semiconductor material, which is photoactive and is capable of generating

electron hole pair when light (photons) is incident on its surface. One of the

advantages of photo-electrochemical cells is reduction and oxidation reaction

happens at different electrodes eliminating the need for separation of gases.

153

However, chemical stability of materials inside electrolyte solution or water is

a challenging issue.

Schematic diagram of a typical photo-electrochemical cell consisting of

n-type semiconductor photoanode, reference (SCE) and metal cathode for

water splitting is shown in Figure 2.

US DoE has set following benchmarks for commercialization of PEC

water splitting technology for hydrogen production.

Criteria 1: 10% Solar to Hydrogen conversion efficiency.

Criteria 2: Stability against Chemical, electrochemical and photo-

corrosion. Working time of at least 1000-hour without significant

degradation.

Criteria 3: Cost of hydrogen production should be economical.

Figure 2: Schematic diagram of a typical photo-electrochemical cell

consisting of n-type semiconductor photoanode, reference

(SCE) and metal cathode for water splitting.

7.2 Process of water splitting

The crux of water splitting process lies in the redox reaction with the

participation of generated charge carriers through solar radiation at catalyst

surface (or active sites). Materials used for catalysts or electrode preparation

are semiconductor in nature. Therefore, they have a defined band gap which

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is a result of the separation of conduction and valence band. Moreover band

edges also play an important role in the selection of the material. Conduction

band edge should be more negative than the reduction potential of the

hydrogen and valence band edge should be more positive than the oxidation

potential of oxygen for water splitting. When light of a particular wavelength is

incident on the catalyst, electron-hole pair is generated only if the photon

energy is more than the band gap of the material. Electron is then migrated to

the conduction band leaving a hole in the valence band.

Next step is separation of charge carriers and their movement to the

surface of the catalyst. For an efficient process, mean life time of the

generated carriers should be high or recombination rate should be low.

Recombination rate in a semiconductor material is affected largely by crystal

defects. Crystal defects acts as electron traps which neutralizes holes. To

inhibit recombination of electron-hole pair, a co-catalyst is generally used.

Generally used co-catalysts are platinum, nickel, ruthenium, rhodium,

palladium, iridium and rhodium. Another requirement of co-catalysts is to

impede the back reaction in between hydrogen and oxygen. However, in

photo-electrochemical, charges are separated by putting a separate electrode

of aforementioned noble metals.

A research group in Kyoto University, Kyoto, Japan worked on the non-

equilibrium interfacial phenomena occurring under microgravity in water

electrolysis. Once separated electron and hole pair is available, redox

reaction can be conducted on the surface of catalyst/co-catalyst. Hydrogen

ion is reduced to hydrogen gas by the transfer of trapped electron and

hydroxyl ion is reduced to oxygen gas by neutralizing the hole in valence

band. Oxidation reaction in water splitting is a 4-electron transfer process and

therefore, valence band has to be deep enough for transfer of charges.

Reduction at cathode: 2 H+(aq) + 2e− → H2(g)

Oxidation at anode: 2 H2O(l) → O2(g) + 4 H+(aq) + 4e−

7.3 Evaluation Parameters

Evaluation of a water splitting system is done on the basis of amount of

gas (hydrogen and oxygen) evolved in due course of time. Amount of gas is

measured in moles and therefore unit for rate of evolution is mol per unit time

(for instance; µmol/hour). Parameter Quantum Yield can be used to compare

different photoactive material under similar operating conditions (Modern

Aspects of Electrochemistry, New York).

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Number of reacted electrons

Quantum Yield = x 100%

Number of absorbed photons

Actual quantum yield is usually more than the quantum yield mentioned

above. This difference can be computed if the incident light spectrum and

absorption spectrum of the material is known. Overall efficiency can be

computed on the basis of total input energy versus total output energy. In

case of solar hydrogen production, input energy is the incident Sun’s energy

and output energy is the energy content of evolved hydrogen gas.

Output energy of hydrogen

Solar to hydrogen efficiency = x 100%

Energy of incident solar light

(mol H2/s) x (237kJ/mol)

= x 100%

(Inc Power W/m2) X Area (m2)

In photo-electrochemical, another term specified as ‘applied bias

photon to current efficiency’ is more suitable as an external source is usually

required for transfer of charge particles from main electrode to counter

electrode.

Applied Bias solar to hydrogen efficiency

Current density (mA / cm2) x (1.23 – Vbias) (V)

= x 100%

Ptotal (mW/cm2) at AM 1.5G

7.4 National and International Status

Photo-electrochemical water splitting for hydrogen generation is based

on solar energy and water, both of which are renewable sources. Energy for

stationary and transportation applications can be retrieved from hydrogen with

low carbon foot print and climate impact. Ever since in the first report,

Researchers in Kanagawa University, Yokohamaduring1972 demonstrated

the feasibility of hydrogen generation via photo-electrochemical splitting of

water, lot of efforts have been made by different workers across the globe to

exploit this process for commercial production of hydrogen. Main focus of this

research has been to search for an ideal semiconductor that can be used as

efficient photo-electrode in this process. However, the long cherished goal of

reaching at least 10% conversion efficiency has so far remained unachieved.

Working at this efficiency, with photo-current generation at the rate 10-15 mA

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cm-2, would imply that the cost of hydrogen production would be economical.

This would be a cost competitive against the existing costs of conventional

fuels and would make this process commercially viable. Another issue

important in the process is of semiconductor material durability in contact with

PEC cell electrolyte. It is desired that the material should remain stable at

least for 2000 working hours.

Researchers in Yerevan State University, Armeniain2005 has

concluded that among different semiconductors used for PEC water splitting,

the best efficiency is detected in metal oxide photo-electrodes, which were

partially reduced and contained an optimal concentration of impurities. In the

ongoing search for a material with above desired characteristics, in recent

years several new dimensions have been added (plate 1). Use of mixed

oxides, Combinatorial approach and designing of high throughout fast

screening procedures, adoption of density functional theory to screen the

materials, Use of phosphides, Selenides, Graphene and CNT based systems

and layered structure are some recent developments in this field of research.

Besides above mentioned work, research pertaining to geometry orientation

and shaping of nanomaterial (by orthogonalizing direction of light absorption,

charge collection, charge separation/ transportation), exploring bandgap and

band alignment as a function of composition, doping and morphology for

engineering structures, which have features favorable for water photolysis,

are also being explored.

Few of the promising material(s) system for application in PEC water

splitting are given in Plate 1.

The Institute of Minerals and Materials Technology (IMMT),

Bhubaneswar developed functional hybrid nano structures for photo

electrochemical water splitting. The different photo-catalytic materials

developed for hydrogen production through water splitting, which were

continuously operated for 6-7 hours. Among the developed materials like CdS

photo-electrodes and CdS nano-crystal powder photo-catalysts with yield of

800-1000 mg/batch, 0.28 wt% P3HT modified CdS with yield of 4087 µmol/h/g

and CdS-NaNbO3 core-shell nano-rods with yield of 11,901 µmol/h/g, the

CdS-NaNbO3 core-shell nano-rods was found to give maximum hydrogen

production.

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Plate 1: Few of the promising material(s) system for application in PEC

water splitting

7.5 Action Plan

Action plan consists of two main activities: (i) basic R & D towards the

identification, synthesis and laboratory-scale PEC measurements on

prospective materials/material systems; (ii) up-scaling of the

materials/systems found promising with respect to their solar-to-hydrogen

conversion efficiency and stability under longer illumination time. Research

will be conducted under following lines:

I. Laboratory-scale studies on prospective materials and their

performance evaluation

Core activity 1: Exploration on promising semiconductors/systems

Extensive R & D is required to be undertaken concerning the photo-

electrochemical measurements for hydrogen generation via photo-splitting of

water by employing the promising semiconductors. Thin films of the

semiconductors would be converted into electrode by adopting the standard

procedure and used in PEC water splitting studies. For converting films into

electrode, initially an electrical contact would be generated using silver paint

and copper wire. The Ohmic contact so prepared and all the sides of film

Properties required?

Band gap energy ≈ 2 eV

Strong optical absorption

Long life time of charge

carriers

Conduction and Valance

band edges to straddle water

redox potentials

High Stability in electrolytes

Non Toxic & Economical

PEC

Water

Splitting

Material

Issues

Strategies being

tried

Doping

Surface

Modifications

Layered

Structures

Dye

Sensitization

Swift Heavy

Ion irradiation

Mixed Oxides

Systems Investigated:

ResultHighlights

New concepts/ Emerging Trends ………..

Fe2O3-

Graphene

Nano-

composite

Bio-inspired Co-

catalyst CoPi on

the surface

CdSe QD electro-

deposited on α-Fe2O3

films

ZnO modified

with Cu ion

implantation

Nanocomposites Quantum

Dots

Bio inspired

catalysts

Metal Ion

Implantatio

n

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(except the front side) would be sealed with the coating of an opaque and

non-conducting epoxy. So prepared thin film working electrodes would be

used as photo-sensitive working electrode, in conjunction with platinum

counter electrode and saturated calomel electrode (SCE, as reference

electrode), at varying electrolyte conditions. Nature and concentration of the

electrolyte and its pH would also be varied in order to optimize the conditions

of hydrogen evolution. Current (I) – Voltage (V) characteristics of PEC cell

would be studied, both under darkness and illumination. By observing the I-V

plots, onset voltage for photo-current would be determined, and based on

these measurements the performance of PEC cell would be evaluated. As

mentioned above this constitutes the core activity in the proposal. The

sustained R & D effort in this direction by the investigators for the past 15

years has led to few of the promising material-options in this regard that need

to be tested at the next level, which involves their integration with pilot-scale

hydrogen generation reactor and the performance evaluation of such reactors

both under controlled conditions as well under real-time solar illumination.

However, as is evident from the literature survey and the recent emerging

trends in this vital area of research, the material issue is yet not finally settled.

As a matter of fact, each of the existing material-options has its own

drawbacks and the researchers are trying to crack those issues.

Core Activity 2: Scale-up studies and related issues

Moving towards solar energy fed pilot-scale hydrogen generation

reactors such that it can perform efficiently under field conditions, this core

activity has been chalked out. The above mentioned two semiconductor

systems would be investigated for this purpose in the beginning. However,

any new material/ system that promises to be even better as observed under

core activity 1, would also be incorporated in the work-plan under this activity.

Key work elements involved, especially pertaining to the synthesis of large

area electrodes would be as:

Suitable synthesis methods as described in objectives to be used for

preparation of electrodes.

First-level up-scaling studies with existing facilities at Dyalbagh

Educational Institute, Agra. Electrodes of at least 3 different

dimensions to be fabricated and tested under controlled laboratory

conditions.

Scaling of electrodes from 1cm2 to 150 cm2 active area. Feasibility of

maximum area of electrode (150 cm2) to be determined by conducting

experiments. These experiments will be conducted with state of the art

instruments at IOC-R&D which is a part of the procurement activity of

the present project plan. Two routes of large area electrodes shall be

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explored – one having single large area electrode and the other –

several small electrodes connected in suitable configuration so as to

result into large area exposure

Empirical modeling of performance versus increase in the area of

electrodes. Determining maximum feasible size of the electrode that

can be incorporated in the reactor.

Study on scaling of counter electrode with respect to increase in the

area of working electrode.

Optimization of interconnection design for working and counter

electrodes.

II. Studies on reactor design and fabrication.

Core Activity 3: Designing the Reactor

Designing reactor: Theoretical modeling and testing

Study of different losses associated with electrode and electrolyte

interfaces.

Qualitative and quantitative study of electrolyte and electrode

resistance components.

Study on feasibility of packaging electrodes in parallel connections,

their associated losses and optimum size possible for a reactor.

Core Activity 4: Fabrication of Reactor

Actual design of the reactor will be taken up after study on electrodes.

Key step of the work planned are mentioned below:

A lab scale reactor will be fabricated to support scale-up activities for

performance evaluation of electrodes of different sizes. Basic design

would be similar to that of a twin compartment reactor. Separate

compartments will be available for working and counter electrode. This

will eliminate need for the separation of evolved gases (hydrogen and

oxygen). Moreover, reactor will be air tight and provision will be made

to sample evolved gases for analysis. Furthermore, an additional

provision will be provided to input feed without opening the reactor or

without interrupting the ongoing process.

An electronics circuit will be designed to supply constant external bias

to the electrodes. Initially battery will be used for supply and

subsequently efforts will be laid to try to use photovoltaic panel for

supplying external bias to electrodes.

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A bigger bench scale reactor will also be fabricated as a part of the

project. This bench scale reactor will exhibit a maximum active area of

~ 900cm2. All the challenges faced in the lab scale reactor will be

addressed in the design of this reactor. Bench scale reactor will also

have the provision of two compartments wherein both the hydrogen

and oxygen gases can be separated. Benchmark data will be

generated by controlled indoor testing with large area illumination

continuous light solar simulator.

Core Activity 5: Fabrication of Reactor

Performance evaluation

Under controlled laboratory conditions

It is proposed to set up a continuous solar simulator in laboratory which

can illuminate electrodes up to a maximum area of~ 900 cm2.

Under real-time solar illumination outdoor field conditions

Real-time testing will be taken up after laboratory testing. Performance

will be evaluated with respect to the real time data obtained from a

weather station already in place at IOC-R&D.

7.6 Summary and Recommendations

Among the various material groups for the photo-electrodes,

semiconductor metal oxides are relatively inexpensive and have a better

photo-chemical stability, many metal oxides have been extensively studied

and significant progress has been achieved in past two decades both

nationally and internationally.

Among the metal oxides; Iron, copper, bismuth vanadium and zinc

have been researched globally for their performance in photo water splitting.

Promising results have been achieved with aforementioned metal oxides;

nano-wire arrays of hematite has shown a promising current density of 3.44

mA/cm2, oxides of Bismuth has been reported with current density up to 2.3

mA/cm2, current density of the order of 2.34 mA/cm2 for Cu2O sample (1 at. %

Ag) under visible light illumination at 0.8 V/SCE has been reported.

While the search for new and more efficient semiconductor

materials/systems for above application would continue, studies are also

needed on up scaling the device by initiating R & D efforts in this direction.

Metal oxides, viz. Fe2O3, TiO2, ZnO, CuO, Cu2O, SrTiO3, BaTiO3 etc are

important class of semiconductors, viewed largely as prospective material

systems for PEC applications. Further, in order to overcome certain limitations

associated with these metal oxides, these were subjected to various

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modifications viz. doping, swift heavy ion irradiation, dye sensitization etc.,

yielding varied improvements on their performances. Nanocomposites, bio-

inspired systems, quantum dots, and ion implantation are amongst the

different newly emerged concepts that have drawn the attention of

researchers and are being investigated with lot of hope and expectations.

Research on scale-up and reactor is equally important as that of the

material research. Efficient and reliable materials need to be studied further

for scalability. Demonstration at lab scale and pilot scale can be significant

towards realizing the ultimate potential of the technology.

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163

HYDROGEN PRODUCTION

BY OTHER TECHNOLOGIES

164

165

8.0 Hydrogen Production by Other Technologies

8.1 Hydrogen Production by non-thermal plasma assisted direct

decomposition of hydrogen sulphide

8.1.1 Hydrogen Sulfide is an inorganic compound that causes severe odor

problems. The emission of Hydrogen Sulfide from petroleum industry, coal

gasification and animal industry has to be regulated as the odor threshold for

Hydrogen Sulfide is 1 ppbv. Hydrogen sulphide occurs as a by-product in the

production of coke form sulfur- containing coal, the refining of Sulphur-

containing crude oils, the production of carbon disulphide, the manufacturer of

viscose rayon, and in the Kraft process for producing wood pulp. Hydrogen

sulphide is the most dangerous of the gases produced by the anaerobic

decomposition of manure. Large amounts of Hydrogen Sulfide are produced

worldwide, mostly from natural gas production and oil refining. Yearly

tonnages of H2S can be deprived from sulfur production, 14.4 million tons

from sour gas and 9.6 from refineries, worldwide. This sour gas potentially

contained about 342, 000 tons (3.8 billion cubic meters) of hydrogen. Oil

refineries and upgraders use hydrogen as well as make H2S, and for this

reason constitute a logical location for a H2S dissociation plant.

Conventional methods to controls hydrogen Sulfide include absorption

(wet scrubbing), absorption, incineration (thermal and/or catalytic), and bio-

filtration. The widely employed Claus method is based on partial combustion

of hydrogen sulfide into sulfur dioxide followed by the catalytic conversion of

H2S + SO2 mixture into elemental sulfur and water. Earlier methods were

focused on recovery of elemental sulfur, however the desired reaction would

be the production of hydrogen by direct oxidation of hydrogen Sulfide, which

is endothermic and thermodynamically unfavorable.

An alternative approach is to use Non-thermal Plasma (NTP)

generated at atmospheric pressure and room temperature. NTP, the fourth

state of the matter consists of energetic electrons, radicals, atoms and

molecules. At low consumption of energy, NTP produces highly energetic

electrons that initiate the chemical reaction leaving the background gas nearly

at room temperature. Recently dielectric barrier discharge (DBD) reactor with

catalytic sintered metal fibre (SMF) electrode has been tested for the

abatement of volatile organic compounds. It was demonstrated that the metal

oxide modified SMF electrodes, performance of the NTP technique could be

improved.

8.1.2 International Status

It is known since long that strong healing decomposes hydrogen

sulphide. Thermal decomposition has recently been implemented at the pilot

166

scale at a gas plant in Alberta. Conversions close to equilibrium have been

observed. An economic study showed that costs for thermal decomposition

would be close to those for conventional processes. Improvements in

separation technologies are needed to enable commercial implementation of

thermal decomposition.

As of today there is no commercial technology for the production of

hydrogen from hydrogen sulphide. The conventional method for hydrogen

sulphide removal is the Claus process, which produces sulfur and water

instead of hydrogen and sulfur that are beneficial. Besides sulfur recovery

limitations, major disadvantage of the Claus process is that the valuable

product hydrogen is converted into water. Moreover, the cost of tail gases

cleanup from Claus plant can exceed the value of sulfur recovered if the

environmental regulations become more stringent. Regarding the catalytic

process, only limited information has been reported, where none of the

catalysts was promising. One of the reasons could be the severe reaction

conditions like high operation temperature (>2000K). Among the several

techniques tested for the production of hydrogen, Idemitsu Kosan Hybrid

(IKC) electrolysis process has been considered as feasible. It is based on

absorption of hydrogen sulphide by Ferric chloride aqueous solution followed

by electrolysis to generate hydrogen and sulfur. IKC process consumes 3.6

kWh/Nm3 hydrogen, whereas steam reforming of methane, the traditional

approach for hydrogen production demands still higher energy of 4.3

kWh/Nm3hydrogen. Like-wise, 40% conversion of hydrogen sulphide by

thermal decomposition can be achieved at temperature ~ 1500K, which is

equivalent to 2.76kWh/Nm3 of hydrogen. At this temperature considerable

amount of by-products like SH were produced. Formation of pure Sulphur and

hydrogen was observed only above 2273K. The practical limitation of this

technique is the operating conditions and separation of products at this

temperature. The main advantage of carrying out hydrogen sulphide

decomposition in the novel DBD reactor is the production of hydrogen in an

economically feasible manner under ambient conditions.

8.1.3 National Status

Most of the research in this area has been focused on

catalytic/photocatalytic decomposition of hydrogen sulphide. However, in both

the cases, catalyst deactivation due to the deposition of sulphur decreases

the efficiency. But, photocatalytic decomposition of hydrogen sulphide to

hydrogen and sulphide offers some promise. Hydrogen sulphide under visible

light to generate hydrogen is an attractive route of solar energy conversion,

because hydrogen is 100% environmentally clean chemical fuel in its cycles

of generation and utilization. Although hydrogen generation from water in

visible light represents a potentially viable route of solar energy conversion, till

date only marginal conversion efficiency has been achieved (5.1% quantum

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yield with sacrificial agents and 2.5 % from pure water. Obviously, the

difficulty in achieving high efficiency is attributed to the involvement of many

high energetic reactive species in the thermodynamically uphill water spilling

reaction.

The Indian Institute of Technology Hyderabad developed the process

of non-thermal plasma assisted direct decomposition of hydrogen sulphide

into hydrogen and sulphur. This process is feasible and advantageous over

Claus process where sulphur alone is recovered from hydrogen sulphide. It is

possible to achieve hydrogen production at about 160 kJ/mole that

corresponds to energy conversion of 2 kWh/Nm3 of hydrogen, which is less

than the energy required for hydrogen production from SMR (about 346

kJ/mole of hydrogen). A packed bed configuration with glass tubes reactor

showed best performance of the reactor which was attributed to the change in

discharge properties. MoOx supported on Al2O3 catalysts showed better

conversion compared to CoOx and NiO due to deactivation of CoOx and NiO

quickly due to sulphur poisoning. Hydrogen production of 0.5 litre/minute was

achieved in the laboratory.

The NTP technology is environmentally friendly and operationally

simple. Another advantage of the suggested process is that the hydrogen

produced is free from impurities, hence secondary purification can be

avoided. The reaction conditions can be still improved to decrease the energy

consumption.

8.2 Hydrogen Production by Photo-splitting of Hydrogen Sulphide

8.2.1 Hydrogen sulphide is a toxic gas occurs widely in natural gas fields and

is produced in large quantities as a byproduct in the coal and petroleum

industry. Currently this toxic gas is converted into sulphur using Claus’s

process or released into the atmosphere. Photo-splitting of hydrogen sulphide

into hydrogen can be an attractive option by conventional the Claus’s process.

Hydrogen sulphide Cleavage process might be used in industrial procedures

where hydrogen sulphide or sulphides are formed as a waste whose rapid

removal and conversion into hydrogen is desired. Currently, for this

application oxide catalysts have been studied but due to certain limitations,

researchers are trying to develop catalyst which can absorb maximum part of

solar radiation and are active under natural solar light. Extensive work has

been carried out for the development of ultraviolet driven photocatalyst for

water and hydrogen sulphide splitting. However, there is a demand for highly

efficient photocatalyst for production of hydrogen under visible light irradiation.

Stability and efficiency of these catalysts still low and need improvement.

There is need to develop prototype photo reactor for hydrogen production

from hydrogen sulphide using solar energy and field trials using gas emitted at

refinery sites using a batch type photoreactor.

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8.2.2 International Status

Semiconductors mediated heterogeneous photocatalysis has become

an attractive technology for environmental pollution remedy, particularly due

to its potential to degrade a wide range of inorganic and organic compounds

in both waste gases and water. The initial reaction step consists of of

electron-hole pair’s production by irradiating the semiconductor with light

having an energy content equal to or higher than the band-gap of

semiconductor. After separation of photogenerated electrons and holes due to

trapping by species adsorbed on the semiconductor, redox reactions occur

between trapped electrons and holes and adsorbate. Most of the

semiconductor photocatalysts investigated are metal oxides (e.g. TiO2, ZnO,

SnO2, WO3) and chalcogenides (e.g. CdS, ZnS, CdSe, ZnSe, CdTe) [1-5]. As

hydrogen-based power and transportation technologies develop the need for

an effective hydrogen source to power fuel cells in the hydrogen economy.

Hydrogen from photo-electrochemical cells is believed to offer the prospect of

such a source. Photocatalytic splitting of water using n-type TiO2 under UV

illumination was first reported over 30 years ago by Researchers in Kanagawa

University, Yokohama. Since then a number of photocatalytic compounds

have been investigated with the aim of improving catalyst activity and stability

in the irradiated aqueous environment. In 2001 Zou et al. first demonstrated

the direct splitting of water by visible light over an In1.xNixTaO4 photocatalyst.

As energy conversion devices, water-splitting photo-electrochemical cells

convert photon energy to the Gibbs free energy of hydrogen and Oxygen via

excited electron states in the photocatalyst. These excited electron states

result from the promotion of valance band electron to a level above the

conduction band edge on the absorption of an incident photon. In practice,

any energy in the excess of the bandgap energy will be dissipated as heat

since electrons promoted to higher states readily thermalise to the conduction

band edge. Internationally, the research on hydrogen generation from

hydrogen sulfide and water is still at academic level. No commercial process

has been developed yet. Many groups in Japan, Korea, U.S, Europe is

working on development of active photocatalysts for hydrogen generation

under visible light irradiation. University of Tokyo, Japan has done extensive

work on photocatalysts for water splitting and recently has reported many UV

and visible light catalysts.

Considering the depletion of other energy sources, it is quite essential

to develop new sources of energy. Development of active photocatalyst for

photo-hydrogen generation will be advantageous for future energy demand.

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8.2.3 National Status

In India, large number of groups is working on photocatalytic

decomposition of organic waste and toxic materials. Very few groups are

working on photocatalytic splitting of water and hydrogen and hydrogen

sulphide into hydrogen under visible light. Few research group in BARC are

working on photocatalytic degradation of nuclear waste as well as water

purification. Some research teams in IISc, Bangalore are working on TiO2

based photocatalysts for organic waste degradation. In addition to this, some

researchers in IIT, Mumbai and Madras, CECRI, Karaikudi, IICT, Hyderabad

and few universities in India are working on photodecomposition of organic

pollutants. But the photo catalysis work has not crossed the development of

other possible new active photocatalyst other than TiO2andCdS. The current

trend in the country is only the degradation of waste or organic using TiO2/Cds

photocatalyst. Only C-MET Pune is working on hydrogen generation by

photocatalytic decomposition of toxic hydrogen sulphide. In India, the

development of active photocatalyst for pure hydrogen generation by water

and hydrogen sulphide splitting is still at academic level. It is essential to

develop catalysts useful under solar light for the decomposition of

water/hydrogen sulphide into hydrogen. The hydrogen sulphide from the

refinaries and mines is continuously emitted into the atmosphere as a result

air in the bin such areas is highly polluted. C-MET is developing new class of

photocatalysts which are stable and active under sunlight.

The Centre for Materials for Electronics Technologies (C-MET), Pune

has developed the prototype photo reactor for hydrogen production from

hydrogen sulphide at the rate of 8182.8 and 7616.4 µmol/h/g was obtained

from nanostructured ZnIn2S4 and CdIn2S4, respectively under Natural Sunlight

(UV optical absorption edge at 557nm for ZnIn2S4 and 576nm for CdIn2S4).

The reactor has been designed for the facile operation and considering the

safety aspects. The sparger was fixed as a H2S distributer, which also acts as

a particle disperser. This design is useful for continuous operation at large

scale.

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171

ACTION PLAN

172

173

9.0 Action Plan

9.1 Hydrogen is a byproduct along with the production of caustic soda and

chlorine in the Chlor-Alkali units. These units are continuously working

towards better utilization of hydrogen and have succeeded in achieving 90%

utilization during 2014-15. The remaining hydrogen amounting to around

6600 tonnes may be utilized in energy related applications, since it emits no

pollution except water and heat. This hydrogen may be used directly for the

generation of power / in transportation applications (vehicles) based on IC

engine technology. For fuel cell application, hydrogen may further be purified

(if required), for use in stationary power generation and on-board application

in vehicles / material handling systems (based on fuel cell technology), etc.

9.2 Hydrogen has been produced from the conventional sources i.e.

carbonaceous fuels like natural gas, coal etc. For small capacities hydrogen

production by electrolysis, methanol or ammonia cracking for small, constant

or intermittent requirements of hydrogen in food, electronics and

pharmaceutical industries and for larger capacities steam reforming of

hydrocarbons / syngas are preferred. These sources release CO2 in the

atmosphere. The average rate of growth of CO2 in the atmosphere is around

2.1 ppm per year and its concentration in air has increased from 381.90 ppm

in 2006 to 398.55 ppm in 2014. India has proposed to reduce emissions by

33-35% by 2030 over the 2005 levels by boosting clean (non-fossil &

including renewable) energy in electricity generation to 40% (at least another

150GW) and by adding sinks through trees and forests. Renewable-based

processes like solar- or wind-driven electrolysis and photo-biological water

splitting hold great promise for clean hydrogen production; however,

advances must still be made before these technologies can be economically

competitive. Thus, hydrogen production may be continued from the

conventional (carbonaceous) fuels through the most competitive process

namely auto-thermal reforming (steam reforming and partial

oxidation)process till the technologies for hydrogen production from

renewable sources become economically competitive.

9.3 Biomass has been identified as potential renewable source for

hydrogen production. It is carbonaceous source and produce CO2, which is

released to the atmosphere. Biomass is gasified to hydrogen rich syngas,

which may be reformed and purified to yield pure / near pure hydrogen. The

technology is being developed in the country by IISc, Bangalore. Some other

institutes like NIT, Rourkela and NIT Cochin have also been engaged in R&D

work for hydrogen production through gasification of biomass. IISc developed

a prototype for production of 2 kg/h hydrogen through Oxy-steam gasification

process with hydrogen yield of 100 gm/kg of biomass used.

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9.4 Electrolysis is a method by which hydrogen may be obtained in pure

form. This hydrogen may be used directly in the fuel cells applications. The

cost of hydrogen production by this method is high due to high capital

investment and operating cost (i.e. electricity consumption). Electricity

generated by the solar energy / wind energy / hydro resource may be used to

nullify carbon emission in the atmosphere, but these technologies require high

capital investment. The electrolyser system consists of various subsystems

like electrochemical stack, power rectifiers, control systems, instrumentation

for monitoring various processes, water purification, pumps, multistage

compressors, pressure vessels, and multiple number of other engineering

subsystems involved and requires integration as per customer requirements

to develop complete system. Except an electrochemical stack, India has core

strength for manufacturing majority of aforementioned subsystems and very

much capable in system engineering. Imported electrolyser stacks in different

combinations may be used and integration can be carried in the country. The

institutions / industry may be identified to work in PPP Model for

commercialization of the balance of plant and simultaneously, the technology

for the production of stack may be procured or developed indigenously.

9.5 Solid polymer electrolyser (SPE) with 20,000 hours of operation are

desirable. SPE is either acid or alkali based, the acid based electrolysis

system requires noble metal catalysts, and alkaline membrane based

electrolysis require cheaper electro catalyst like Nickel. It is ideal to have

membranes based alkaline water electrolysis system integrated with solar

photovoltaic system. However, alkaline based SPE faces numerous

challenges such as chemical stability in the electrochemical device. These

challenges are lesser for either phosphoric acid based electrolysis cells or

alkali based electrolysis systems using diaphragm. Due to these problems,

the following steps are suggested in the sequential order:

(i) Deployment of solar energy powered

a. Acid based electrolysis system

b. Alkali based electrolysis system

for immediate onsite hydrogen production using available technology.

(ii) Development of ectrolysers based on indigenous acid based SPE

(iii) Development of alternate alkaline membrane

(iv) Development of alkaline SPE based electrolyte system

(v) Replacement of old systems by the newly developed systems

9.6 Hydrogen may be produced through dark and photo-fermentation

process. The dark fermentation has certain limitations and can yield hydrogen

in terms of energy recovery ranging 20 to 30 % of total energy. This process

175

may be integrated with photo fermentation, but such a two-stage process is

difficult to commercialise. However, theoretically, 12 moles of H2 /mole of

glucose can be recovered. If the dark fermentation followed by bio-methantion

process may lead to gaseous energy recovery ranging from 50 to 60%. In this

process the same reactor may be used for H2 production and later for bio-

methanation, which would curtail the operational cost. The mixture of

hydrogen and methane so produced is called bio-hymet. The production bio-

hymet could be envisioned as renewable source of energy only when it would

be produced from renewable sources. Any organic compound which is rich in

carbohydrates, fats and proteins could be considered as possible substrate

for bio-hymet production. Another path of hydrogen economy has been

suggested by the integration of fuel cell system with the bio-hydrogen

production system. Such setups may be put strategically near to those places

where supply of feedstock is easily available in adequate quantities. The

electricity generated by such system may electrify villages in a decentralized

manner.

9.7 Bhabha Atomic Research Centre has successfully demonstrated I-S

process in closed loop operation in glass/quartz material in the laboratory. It is

further planned to demonstrate closed loop operation in metallic construction.

Other institutes / organisations will also be roped in depending upon their

capabilities. The broad plan is given below:

(i) Design and demonstration of atmospheric pressure operation all metal

closed loop system (AMCL).

(ii) High pressure operation Bunsen reactor system has been designed

and its commissioning is underway.

(iii) Design and demonstration of high pressure sulfuric acid

decomposition system.

(iv) Design and demonstration of hydroiodic acid distillation and

decomposition system.

(v) Integration of all three high pressure systems to demonstrate, high

pressure closed loop process.

The following challenges have been envisaged for the metallic system,

which are to be dealt with in this endeavor:

(i) Fabrication of exotic material based equipment, such as Tantalum,

Hastelloy, Silicon Carbide etc.

(ii) Development of special seals, compatible for high temperature, high

pressure and corrosive chemicals for metallic system.

(iii) Development of special instrumentation and controls for metallic

system.

176

9.8 ONGC Energy Centre (OEC) is of the view that three potential thermo-

chemical processes (Cu-Cl closed loop cycle, I-S closed loop cycle and I-S

open loop cycle) first be studied at engineering scale and compared before

deciding to take up at the commercial level. The OEC has planned to study

and evaluate alternative materials used in process and plant design, keeping

in view the corrosive nature and use of expensive materials in the process.

The following work has been undertaken by the Centre:

(i) Indigenous membranes are being developed with CSMCRI, Bhavnagar

and expected to be completed by January, 2018.

(ii) Development of partially open-loop I-S cycle involving H2S incineration,

experimental studies on Bunsen reaction and HI decomposition would

be completed within two years with IIP Dehradun.

(iii) Work on “Prolonged stability tests of catalysts for HI decomposition

reaction of I-S cycle have recently been taken-up jointly with IIT-Delhi.

(iv) Suitable materials for design and development of process reactors for

I-S cycle are being identified. The work is in progress.

The OEC has planned to start research on identification, development

and testing of suitable materials for design and construction of large size

indigenous reactors for Cu-Cl process, keeping in view the corrosive nature of

materials used in the Cu-Cl process.

9.9 Photo-electrochemical Water Splitting

Indian Oil Corporation Limited Research and Development Centre,

Faridabad made a plan to conduct laboratory-scale studies on prospective

materials and their performance evaluation. The details are given below:

Core activity 1: Exploration on promising semiconductors/systems:

Extensive R & D is required to be undertaken concerning the photo-

electrochemical measurements for hydrogen generation via photo-splitting of

water by employing the promising semiconductors. Thin films of the

semiconductors would be converted into electrode by adopting the standard

procedure and to be used in PEC water splitting studies. These thin film

working electrodes would be used as photo-sensitive working electrode, in

conjunction with platinum counter electrode and saturated calomel electrode

(SCE, as reference electrode), at varying electrolyte conditions. Current (I) –

Voltage (V) characteristics of PEC cell would be studied, both under darkness

and illumination. The performance of PEC cell would be evaluated. Promising

material-options in this regard that need to be tested at the next level, which

would be involved their integration with pilot-scale hydrogen generation

reactor and the performance evaluation of such reactors both under controlled

conditions as well under real-time solar illumination.

177

Core Activity 2: Scale-up studies and related issues: Solar energy fed

pilot-scale hydrogen generation reactors to perform efficiently under field

conditions will be developed. The above mentioned two semiconductor

systems would be investigated. New promising material/ system would also

be incorporated in the work-plan under this activity. Key work elements

involved the synthesis of large area electrodes including suitable synthesis

methods for preparation of electrodes. First-level up-scaling studies with

existing facilities at Dyalbagh Educational Institute, Agra will be done.

Electrodes of different dimensions need to be fabricated and tested.

Feasibility for scaling of electrodes from 1cm2 to 150 cm2 active area is to be

determined by conducting experiments with state of the art instruments at

IOCL - R&D. Two routes of large area electrodes shall be explored – one

having single large area electrode and the other – several small electrodes

connected in suitable configuration. Empirical modeling of performance

versus increase in the area of electrodes will be done. Maximum feasible size

electrode will be determined that can be incorporated in the reactor. Study on

scaling of counter electrode with respect to increase in the area of working

electrode and optimization of interconnection design for working and counter

electrodes would be done.

III. Studies on reactor design and fabrication.

Core Activity 3: Designing the Reactor: Theoretical modeling of reactor will

be designed and tested. Different losses associated with electrode and

electrolyte interfaces will be studied. Qualitative and quantitative study of

electrolyte and electrode resistance components will be taken up. Feasibility

of packaging electrodes in parallel connections, their associated losses and

optimum size possible for a reactor will be studied.

Core Activity 4: Fabrication of Reactor: Actual design of the reactor will be

taken up after study on electrodes. A lab scale reactor with a twin

compartment reactor will be fabricated to support scale-up activities for

performance evaluation of electrodes of different sizes. Separate

compartments will separate the evolved gases (hydrogen and oxygen).An

electronics circuit will be designed to supply constant external bias to the

electrodes. Initially battery will be used for supply and subsequently efforts will

be laid to try to use photovoltaic panel for supplying external bias to

electrodes. A bigger bench scale reactor having the provision of two

compartments will also be fabricated with a maximum active area of ~

900cm2. Benchmark data will be generated by controlled indoor testing with

large area illumination continuous light solar simulator.

Core Activity 5: Fabrication of Reactor: Performance is to be evaluated

under controlled laboratory conditions. It is planned to set up a continuous

178

solar simulator in laboratory which can illuminate electrodes up to a maximum

area of~ 900 cm2.

Under real-time solar illumination outdoor field conditions testing will be

taken up after laboratory testing. Performance will be evaluated with respect

to the real time data obtained from a weather station at IOCL-R&D.

9.10 Presently, Hydrogen Production by non-thermal plasma assisted direct

decomposition of hydrogen sulphide is at research and development stage

and no commercial technology is available. Electrolysis process consumes

3.6 kWh/Nm3 hydrogen, whereas steam reforming of methane, the traditional

approach for hydrogen production demands still higher energy of 4.3

kWh/Nm3 hydrogen. 40% conversion of hydrogen sulphide by thermal

decomposition can be achieved at temperature ~ 1500K. Nationally, most of

the research in this area has been focused on catalytic/ photocatalytic

decomposition of hydrogen sulphide. Hydrogen sulphide under visible light to

generate hydrogen is an attractive route of solar energy conversion, because

hydrogen is 100% environmentally clean chemical fuel. The Indian Institute of

Technology Hyderabad developed the process of non-thermal plasma

assisted direct decomposition of hydrogen sulphide into hydrogen and

sulphur. Hydrogen production of 0.5 litre/minute was achieved in the

laboratory. The reaction conditions can be still improved to decrease the

energy consumption. Further R&D is required in this area.

9.11 For the photo-splitting of hydrogen sulphide into hydrogen, extensive

work has been carried out in the development of ultraviolet driven

photocatalyst for water and hydrogen sulphide splitting. There is need to

develop prototype photo reactor for hydrogen production from hydrogen

sulphide using solar energy and field trials using gas emitted at refinery sites

using a batch type photoreactor. The research on hydrogen generation from

hydrogen sulfide and water is still at research level. No commercial process

has been developed yet. Nationally, very few groups are working on

photocatalytic splitting of water and hydrogen and hydrogen sulphide into

hydrogen under visible light. Few research group in BARC are working on

photocatalytic degradation of nuclear waste as well as water purification.

Some research teams in IISc, Bangalore are working on TiO2 based

photocatalysts for organic waste degradation. In addition to this, some

researchers in IIT, Mumbai and Madras, CECRI, Karaikudi, IICT, Hyderabad

and few universities in India are working on photodecomposition of organic

pollutants. The Centre for Materials for Electronics Technologies (C-MET),

Pune is working on hydrogen generation by photocatalytic decomposition of

toxic hydrogen sulphide. C-MET is developing new class of photocatalysts

which are stable and active under sunlight. C-MET, Pune has developed the

prototype photo reactor for hydrogen production from hydrogen sulphide at

179

the rate of 8182.8 and 7616.4 µmol/h/g was obtained from nanostructured

ZnIn2S4 and CdIn2S4, respectively under Natural Sunlight. This design is useful

for continuous operation at large scale. There is a scope to carry R& D in this

area.

9.12 The Institute of Minerals and Materials Technology (IMMT),

Bhubaneswar developed functional hybrid nano structures for photo

electrochemical water splitting. The different photo-catalytic materials

developed for hydrogen production through water splitting, which were

continuously operated for 6-7 hours. Among the developed materials like CdS

photo-electrodes and CdS nano-crystal powder photo-catalysts with yield of

800-1000 mg/batch, 0.28 wt% P3HT modified CdS with yield of 4087 µmol/h/g

and CdS-NaNbO3 core-shell nano-rods with yield of 11,901 µmol/h/g, the

CdS-NaNbO3 core-shell nano-rods was found to give maximum hydrogen

production. Research & Development may be continued in this area.

180

181

FINANCIAL PROJECTIONS AND TIME

SCHEDULE OF PROJECT ACTIVITIES

182

183

10.0 Financial Projections

10.1 Hydrogen Production from Carbonaceous Feed-stock like Natural Gas,

Coal etc. using Thermo-chemical Route

(i) Mission Mode Projects: Scaling-up of the process of partial

reforming of natural gas for the production of H-CNG for the use in

vehicles (upto 2019) - Rs.40 Crore

(ii) Research and Development Projects: Development &

demonstration of hydrogen production by auto-thermal process

(upto 2020) - Rs. 20 Crore

(iii) Basic / Fundamental Research Projects: Dissociation of

gaseous hydrocarbon fuels to hydrogen using solar energy (upto

2022) - Rs. 10 Crore

10.2 Hydrogen Production from Carbonaceous Source like Biomass Feed-

stock as Renewable Source using Thermochemical Route

(i) Mission Mode Projects: Research and development for hydrogen

production by gasification of biomass, including demonstration of

technology at pilot scale (upto 2020) - Rs. 10 Crore

(ii) Research and Development Projects: Hydrogen production by

reformation of bio-oil obtained from fast pyrolysis of biomass (upto

2022) - Rs.5 Crore

10.3 Hydrogen Production using Electrolytic Processes - Low and High

Temperature Electrolysers

(i) Research and Development Projects: Development &

demonstration of 1 Nm3/hr high temperature steam electrolyser

and 5 Nm3/hr indigenously developed solid polymer water

electrolyser (upto 2020) - Rs. 10 Crore

(ii) Research and Development Projects: Development &

demonstration of efficient alkaline water electrolyser (upto 2018)

- Rs. 10 Crore

(iii) Research and Development Projects: Development and

demonstration of clean and sustainable hydrogen production by

splitting water using renewable energies such as solar energy,

wind energy and hybrid systems. This also includes electrolysis,

photo-catalysis and photo-electro-catalysis (upto 2022)

-Rs. 10 Crore

iv) Integration of large capacity electrolysers with wind / solar power

units when there are not in a position to evacuate power to grid for

providing hydrogen (upto 2022). -Rs. 5 Crore

184

10.4 Bio-Hydrogen Production

i) Mission Mode Projects: Development and demonstration of

biological hydrogen production from different kinds of wastes like

effluents from distillery, brewery, paper mills, wastewater from city,

dairy, tannery, slaughter house, chemical & pharmaceutical

industries, agro / food processing industry residues like cane

molasses, noodle and potato processing, poultry litter, de-oiled

algal cakes, food (canteen) waste through dark or/and photo

fermentation. Demonstration of prototypes at various levels

followed by bench scale and pilot plant. After successful

demonstration commercial production may be commenced (Upto

2022) -Rs.20 Crore

ii) Mission Mode Projects: Hydrogen production by water splitting

using photolysis using solar energy (Upto 2022) -Rs.40 Crore

iii) Research and Development Projects: Hydrogen production

together with methane through biological processes from different

kinds of organic wastes, including industrial effluent. Energy

balance and process economic aspects may also be studied (Upto

2019) - Rs.10 Crore

iv) Research and Development Projects:Development of

technology for production of syn-gas (CO+H2)and hydrogen from

reformation of natural gas / biogas using solar energy (up to 2022.

- Rs.5 Crore

10.5 Hydrogen Production through Thermochemical Cycles

Mission Mode Projects: Hydrogen production by water splitting using

thermo-chemical route (open / closed loop Iodine-Sulphur cycle and

Copper – Chlorine cycle) using solar / nuclear heat (upto 2022)

- Rs.50 Crore

10.6 Other innovative method for hydrogen production such as hydrogen

production by non-thermal plasma assisted direct decomposition of

hydrogen sulphide, Photo-splitting of Hydrogen Sulphide including

developmental effort for reduction in energy consumption for hydrogen

production (up to 2022). -Rs.20 Crore

10.7 Projects for utilization of byproduct hydrogen at Chlor-Alkali units /

refineries: Development and demonstration of prototype systems for

purification of by-product hydrogen from Chlor-Alkali units / refineries

for the use in fuel cells to generate power for captive use or its

185

compression for filing in cylinders to use them on-board in hydrogen

fueled vehicles / material handling systems (based on fuel cell

technology) (Upto 2019) - Rs.20 Crore

_______________

Total requirement (Upto 2022) -Rs.285 Crore

______________

186

ACTIVITIES ON HYDROGEN PRODUCTION

MMP: Mission Mode Projects; RD&DP: Research & Development Projects; B/FRP: Basic / Fundamental Research Projects

Sl.

No. Category of Projects

Time Frame (Year) Financial

Outlay

(Rs. in Crore) 2016 2017 2018 2019 2020 2021 2022

1

Mission Mode Projects

20

40

20

40

50

Setting-up of purification unit / compression

system to fill cylinders to utilize surplus

hydrogen from the Chlor-Alkali Units /

Refineries

Scaling-up of the process of partial reforming of

natural gas for the production of H-CNG

Demonstration of closed loop operation of I-S in metallic reactor and both I-S open & closed loop process and Cu-Cl cycle using solar / nuclear heat

SUB-TOTAL 170

Development and demonstration of biological hydrogen production from different kinds of wastes

Phase I Bench Scale

Phase II Pilot Scale

Phase III Commercial Production

Hydrogen production by water splitting through photolysis using solar energy

187

2

Research, Development

& Demonstration

20

10

10

10

10

10 5

5 5

Hydrogen production by gasification of biomass including

demonstration of technology at pilot scale

Development, and demonstration of

electrolyser with indigenous acid based SPE &

alternate alkaline membrane and its

deployment to replace old systems

Development and demonstration of alkaline 1 & 5 Nm3/h high temperature

steam solid polymer water electrolyser and its deployment to replace old

systems

Hydrogen production by Auto-thermal Process

Development of technology for production of syn-gas (CO+H2) and hydrogen from

reformation of natural gas / biogas using solar energy.

Integration of large capacity electrolysers with wind / solar power units, which is not in a

position to evacuate power to grid, for generation of hydrogen and its storage

SUB-TOTAL 85

Development and demonstration of Hydrogen production by splitting water using

renewable energies

Hydrogen production by reformation of bio-oil obtained from fast pyrolysis of biomass

Development & demonstration of

efficient alkaline water electrolyser

188

3.

Basic / Fundamental

Research Projects

10

20

Other innovative method for hydrogen production like hydrogen production by non-

thermal plasma assisted direct decomposition of hydrogen sulphide, Photo-splitting of

Hydrogen Sulphide including developmental effort for reduction in energy consumption

for hydrogen production

SUB-TOTAL 30

GRAND TOTAL 285

Dissociation of gaseous hydrocarbon fuels to hydrogen using solar energy

189

CONCLUSIONS AND

RECOMMENDATIONS

190

191

11.0 Conclusions and Recommendations

11.1 Conclusions

11.1.1 Hydrogen has been widely used in chemical industries to manufacture

fertilizers, chemicals, ammonia, saturated fatty acids (vanaspati ghee), etc. Its

use in non-energy applications is expected to increase further in coming years

substantially. It is an energy career and not a primary source of energy. It is

gaining importance as a futuristic clean (pollution free) and sustainable (on

the basis of its production from renewable sources of energy) fuel for

stationary power generation and transportation. Hydrogen may be produced

from direct or indirect source of energy and hydrocarbon. The fossilized

carbonaceous feed stocks, like natural gas, naphtha or coal, etc., (source of

hydrocarbon and chemical energy) are being used for producing hydrogen

through steam reforming, plasma reforming, coal gasification, partial

oxidation, and co-conversion using steam. Hydrogen is also being produced

from electrolysis of water.

11.1.2 The conventional carbonaceous feed stocks are limited. The non-

fossilized renewable carbonaceous materials, such as biomass, agro-waste,

rubber wastes, urban solid waste, de-oiled seed cakes, waste cooking oil etc.

contain carbon and may be used for producing hydrogen. All these feed-

stocks emit CO2 (a greenhouse gas) and other polluting gases. Hydrogen is

also produced through low or high temperature electrolysis of water, which is

abundantly available on earth. The electricity used for this process may be

generated using fossil fuels or through the use of solar energy / wind energy.

11.1.3 In view of the current developments and efforts at the national level for

the deployment of fuel cells as the back-up power system for the telecom

towers and demonstration of vehicles based on the hydrogen IC engine

technology as well as fuel cells, it is the right time to set-up hydrogen

production facilities on small, medium and large scales to derive meaningful

insights regarding realisation and management of hydrogen energy

infrastructure in the country.

11.1.4 Substantial quantity of surplus hydrogen is available as byproduct

hydrogen. It may be tapped to meet immediate requirement for research,

development and demonstration of various hydrogen based projects. The

Government may consider extending support to create facilities for tapping

this hydrogen. In India, currently the byproduct hydrogen amounting to around

6600 tonnes hydrogen (10% of total byproduct hydrogen) is available as

unutilized with the Chlor-Alkali units. This hydrogen may be further purified (if

required), compressed, bottled and transported to the sites for use in

stationary power generation and on-board application in vehicles / material

192

handling systems, etc. This surplus volume of by-production hydrogen is,

however, quite small to meet the future needs of the gas for energetic uses. A

concerted effort is required to transform the laboratory results into hydrogen

production facilities.

11.1.5 Biomass can be processed (pyrolysed / gasified) for obtaining

hydrogen rich syn-gas. The hydrogen needs to be separated out and purified

to different levels of purity depending on the application needs from the

hydrogen rich syn-gas. The biomass is considered to be easily available in

large quantities. The research outcome of biomass gasification suggests

addressing to the need of hydrogen generation from biomass through the

thermo-chemical conversion process. The R&D experience in the country on

the biomass gasification is rich and can be utilized for technology

development of hydrogen production. Internationally, hydrogen generation by

gasification is being pursued and shortlisted as an economical way to address

to hydrogen production problem.

11.1.6 Water can be decomposed into hydrogen and oxygen through

electrolysis. It is an energy intensive process. The available technologies in

the world’s market are alkaline and solid polymer electrolyte (SPE) based

water electrolyser. Alkaline water electrolysis is cheaper due to use of nickel

catalysts, but efficiency is lower (60-75%) than that (65–90%) of SPE water

electrolysers, which are expensive due to the use of noble metal catalyst (e.

g. platinum) and are operated at higher current densities. The SPE water

electrolysers are possibly, capable of producing cheaper hydrogen, if its

production is taken up on large scale. The efficiency of SPE water electrolyser

is more at higher temperature and pressure (around 120-200 bar). In high

pressure electrolysis external hydrogen compressor is eliminated and hence

around 3 % as average energy consumption for compression of hydrogen is

saved. This SPE based electrolysis process can also be operated with the

electricity generated from the solar photovoltaic systems or wind mills, which

have large potential. Several large installations coupling solar energy or wind

farms with water electrolysers have come up world over. Most of these are

implemented through consortium of several companies. SPE technology up

to 1 Nm3/h has been developed indigenously and its technology has been

transferred to industry.

11.1.7 The thermo-chemical cycles are processes, where water is

decomposed into hydrogen and oxygen via a series of chemical reactions

using intermediates, which are recycled. As the heat can be directly used,

these cycles have the potential of a better efficiency than alkaline electrolysis.

The required energy can be either provided by nuclear energy / solar energy.

The iodine-sulfur closed & open loop (I-S) cycle and Cu-Cl closed loop cycle

are most promising and efficient thermo-chemical water splitting technologies

193

for the massive production of hydrogen. BARC has successfully demonstrated

in the I-S closed loop operation in glass / quartz materials in the country. It

has been planned to take-up demonstration of the same process in metal

construction. The ONGC Energy Centre (OEC) has set-up an engineering

scale plant for Cu-Cl closed loop cycle process, which will be operated for one

year and alternative materials for platinum as electrode has been undertaken

for development at this plant. OEC is also working with CSMCRI, Bhavnagar

on indigenous development of polymeric charged membranes for

thermochemical hydrogen generation processes; with IIP, Dehradun for the

development of partially open-loop I-S cycle involving H2S incineration &

experimental studies on Bunsen reaction and HI decomposition and with IIT

Delhi on prolonged stability tests of catalysts for HI decomposition reaction of

I-S cycle. OEC has also planned to carry out research on identification,

development and testing of suitable materials for design and construction of

large size indigenous reactors for Cu-Cl process, keeping in view the

corrosive nature of materials used in the Cu-Cl process.

11.1.8 Hydrogen can be produced from dark fermentation (equivalent to 20 to

30% of the total energy content of the feed). This process followed by photo

fermentation, 12 moles of H2 /mole of glucose can be recovered theoretically,

but it is difficult to integrate the two processes for commercialization. The

dark fermentation can be integrated with the bio-methantion process (to yield

50-60% gaseous energy recovery), where methane may be produced from

the spent media of the dark fermentation, which is rich in volatile fatty acids

that is an ideal substrate for methanogens. The most attractive point of such

a process is that both the processes may be carried out one after the other in

the same reactor (H2 production followed by bio-methanation. So, separate

reactor is not required. This would lead to decrease in operational cost of the

entire process. Bio-hythane production may be envisioned as renewable

source of energy only when it would be produced from renewable sources.

Any organic compound which is rich in carbohydrates, fats and proteins could

be considered as possible substrate for bio-hymet production.

11.1.9 Steam-methane reforming (SMR) and coal gasification are the

technologies established globally for hydrogen production. They are

commercially ready, though the cost is high. Still there is scope for carrying

out R&D activities for coming out with cheaper catalysts and efficient

reforming units.

11.1.10 Auto-thermal reformers (ATRs) combine some of the best features of

steam reforming and partial oxidation systems. Several companies are

developing small auto-thermal reformers for converting liquid hydrocarbon

fuels to hydrogen for the use in fuel cell systems. The auto-thermal reformer

requires no external heat source and no indirect heat exchangers. Heat

194

generated by the partial oxidation is utilized to drive steam reforming reaction.

This is more compact than steam reformers, and it will have a lower capital

cost and higher system efficiency than partial oxidation systems. Auto-thermal

reformers are being developed for PEMFC system by a number of groups.

11.1.11Solar hydrogen production from direct photo electrochemical (PEC)

water splitting is the ultimate goal for a sustainable, renewable and clean

hydrogen economy. In PEC water splitting, hydrogen is produced from water

using sunlight and specialized semiconductors called photo electrochemical

materials, which use light energy to directly dissociate water molecules into

hydrogen and oxygen. Indian R & D organisations are engaged in the

extensive R & D of photo-electrochemical technology.

11.1.12 The efforts are required to develop other/new innovative method for

hydrogen production, like hydrogen production by non-thermal plasma

assisted direct decomposition of hydrogen sulphide, Photo-splitting of

Hydrogen Sulphide including developmental effort for reduction in energy

consumption for hydrogen production

11.1.13 To start with, the country may adopt technologies from abroad,

especially to build large installations, for which we may not have the expertise

straightaway. For medium and small installations, Indian R & D organisations

and industries could chip in well.

11.1.14 The Ministry may constitute a group of experts, which may review

from time to time, the plan and actual development and deployment of

hydrogen based systems and devices in the field in order to assess the future

hydrogen requirement. The group will then suggest ways and means to fulfil

hydrogen requirement through various technologies being developed in the

country or to be imported from abroad.

11.2 Recommendations

11.2.1 India has announced its Climate Action Plan for reduction of emissions

by 33-35% by 2030 over the 2005 levels, boosting clean (non-fossil &

including renewable) energy in electricity generation to 40% (at least another

150GW), while adding carbon sinks — tree and forest cover to remove carbon

dioxide from the atmosphere — amounting to 2.5-3 billion tonnes of CO2 by

2030. Thus, the country has targeted to enhance nuclear power from 5 GW

to 63 GW by 2032 and doubling wind capacity to 60 GW by 2022, solar

capacity from 4 GW to 100 GW by 2022.

11.2.2 In view of the India’s Climate Action Plan, the technologies for

hydrogen production may be targeted accordingly. The first target may be

195

focused on the efficient utilization of byproduct hydrogen of the Chlor-Alkali

units. At the end of the financial year 2014-15, only 10% of byproduct

hydrogen is available. Remaining 90% byproduct hydrogen is being utilized,

~40% in chemical industries,~37% as fuel in boiler heating for captive use and

~13% being bottled for sale.After utilization of surplus un-utilized 10%

byproduct hydrogen, next target may be made to utilize ~37% hydrogen

efficiently, which is currently being used as fuel in boiler heating for captive

use. Alternate sources may be used for heating purpose. In-house stationary

power generation may be one of the most effective ways of utilizing hydrogen.

The government may consider incentivizing this application of hydrogen for its

cost effective utilization.

11.2.3 The present facilities of hydrogen production may be utilized to supply

hydrogen for purpose of carrying out the activities on the research,

development and demonstration for hydrogen production and its applications

for stationary power generation and vehicles.

11.2.4 From the gap between international and national state of art of

technologies, it has been visualized that India has to take a leapfrog to come

at par with the international level. This gap is to be planned in time bound

project mode (with foreign collaboration, if required) and therefore, the

projects may be classified in the following three categories viz. National

Mission Projects, Research & Development projects and Basic / Fundamental

Research projects:

11.2.5 The National Mission Projects may cover projects with the participation

of the industry for the technologies, which are mature or near maturity for

commercialization after the short development time and those may be taken

up on large scale demonstration. Such projects would be multi-disciplinary in

nature. These projects may involve more than one institution (with a lead

institution), which are already involved in the implementation of research &

development activities. The outcome of such projects should be a compact,

comprehensive, marketable and user friendly product. The resources and the

infrastructure facilities of the involved institutions may be pooled together to

achieve the common goal.

11.2.6 The Research & Development projects may include the projects in

which the technology is at the stage of prototype development and its

demonstration as a proof of concept. Industry participation should be

preferred for these projects. Such projects may be undertaken on different

subjects like design, research & development of the individual system

components, sub-systems, integration of systems after the basic research has

shown encouraging results. Engineering research and development must be

a part of such projects.

196

11.2.7 The Basic / Fundamental Research projects will cover search /

development of new materials for the development of components, catalysts

and new processes in the area of hydrogen production.

11.2.8 These categories may be further elaborated as under:

a) Mission Mode Projects

(i) Development and demonstration of biological hydrogen

production from different kinds of wastes like effluents from

distillery, brewery, paper mills, wastewater from city, dairy,

tannery, slaughter house, chemical & pharmaceutical

industries, agro / food processing industry residues like cane

molasses, noodle and potato processing, poultry litter, de-

oiled algal cakes, food (canteen) waste through dark or/and

photo fermentation. Demonstration of prototypes at various

levels followed by bench scale and pilot plant. After

successful demonstration commercial production may be

commenced.

(ii) Research and development for hydrogen production by

gasification of biomass, including demonstration of

technology at pilot scale.

(iii) Hydrogen production by water splitting using photolysis and

thermo-chemical route using solar and nuclear heat.

b) Research and Development Projects

(i) Hydrogen production together with methane through

biological processes from different kinds of organic wastes,

including industrial effluent. Energy balance and process

economic aspects may also be studied.

(ii) Development & demonstration of 1 Nm3/h high temperature

steam electrolyser (HTSE) and 5 Nm3/h indigenously

developed solid polymer water electrolyser (SPWE).

(iii) Development & demonstration of efficient alkaline water

electrolyser.

(iv) Development and demonstration of clean and sustainable

hydrogen production by splitting water using renewable

energies such as solar energy, wind energy and hybrid

systems. This also includes electrolysis, photo-catalysis and

photo-electro-catalysis.

197

c) Basic / Fundamental Research Projects

(i) Dissociation of gaseous hydrocarbon fuels to hydrogen using

solar energy.

(ii) Any other innovative method for hydrogen production, like

hydrogen production by non-thermal plasma assisted direct

decomposition of hydrogen sulphide, Photo-splitting of

Hydrogen Sulphide, including developmental effort for

reduction in energy consumption for hydrogen production

(d) Projects for Utilization of Byproduct Hydrogen at Chlor-Alkali

Units / Refineries

Development and demonstration of prototype systems for

purification of by-product hydrogen from Chlor-Alkali units /

refineries for the use in fuel cells to generate power for captive

use or its compression for filing in cylinders to use them on-

board in hydrogen fueled vehicles / material handling systems

(based on fuel cell technology).

198

199

BIBLIOGRAPHY

200

201

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12.3 Hydrogen Production using Electrolytic Processes - Low and High

Temperature Electrolysers

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3. Smitha, B., Sridhar, S., and Khan, A. A., Journal of Membrane

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1753, 1999.

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205

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242, 2002.

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11. Rikukawa, R., and Sanui, K., Progress Polymer Science, vol. 25,

pp. 1463-1502, 2000.

12. Genies, C., Mercier, R., Sillion, B., Corner, N., Gebel, G. and

Pineri, M., Polymer, vol. 42, pp. 359-373, 2001.

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18. Haubold, H. G., Vad, T., Jungbluth, H., and Hiller, P., Electrochim

Acta, Vol. 46, pp. 1559-1563, 2001.

12.4 Bio-Hydrogen Production

1. Armor, J. N., “The Multiple Roles for Catalysis in the Production of

H2”, Applied Catalysis A: General. 1999; 176: 159-176.

2. Benemann J R. Hydrogen Biotechnology: Progress and Prospects.

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Production by Clostridium thermolacticum during Continuous

Fermentation of Lactose, Int J Hydrogen Energy. 2004; 29(14):

1479-1485.

5. Oh, Y. K., Kim S. H., Kim, M. S., and Park, S., Thermophilic

Biohydrogen Production from Glucose with Trickling Biofilter.

Biotech Bioengineering. 2004; 88(6): 690–698.

6. Potential for Wastewater Treatment Systems Based on Microbial

Fuel Cells and Biological Hydrogen Production. ACS, Division of

Environmental Chemistry - Preprints of Extended Abstracts. 2004;

44(2):1474-1477.

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Unsaturated, Packed-bed Bioreactor. ACS National Meeting Book

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of Abstracts 2004: 228(1); 300. Abstracts of Papers - 228th ACS

National Meeting; Philadelphia

8. Degliuomini L.N., Biset S., Luppi P., Marta S. Basualdo, A Rigorous

Computational Model for Hydrogen Production from Bio-ethanol to

Feed a fuel Cell Stack, Int J Hydrogen Energy. 2012; 37(4): 3108-

3129.

9. Vatsala, T.M., Raj, M., Manimaran, A., A Pilot-scale Study of

Biohydrogen Production from Distillery Effluent using Defined

Bacterial Co-culture. Int J Hydrogen Energy. 2008; 33(20): 5404-

5415.

12.5 Hydrogen Production through Thermochemical Cycles (Iodine-

Sulphur Cycle)

1. Zhang, P., et al., Overview of Nuclear Hydrogen Production

Research through Iodine-Sulfur Process at INET, International

Journal of Hydrogen energy, 35 (2010 ) 2883 – 2887.

2. IAEA Nuclear Energy Series, No. NP-T-4.2 Hydrogen Production

Using Nuclear Energy, 2013

3. Status of HTTR Project in JAEA, Hirofumi OHASHI, Technical

Meeting on the Safety of High Temperature Gas Cooled Reactors in

the Light of the Fukushima Daiichi Accident, 8 - 11 April 2014, IAEA

Headquarters, Vienna, Austria

4. Greg F. Naterer, Ibrahim Dincer, Calin Zamfirescu Hydrogen

Production from Nuclear Energy, Springer, 2013

12.6 Hydrogen Production by Photo-electrochemical Water Splitting

1. Kudo, A., Miseki, Y. Heterogeneous photocatalyst materials for

water splitting. Chem. Soc. Rev. 2009, 38, 253–278.

2. Kamat, P.V. Graphene-based nano architectures. Anchoring

semiconductor and metal nano particles on a two-dimensional

carbon support. J. Phys. Chem. Lett. 2010, 1, 520–527.

3. H. Matsushima, T. Nishida, Y. Konishi, Y. Fukunaka, Y. Ito and K.

Kuribayashi, Electrochim. Acta, 48 (2003) 4119.

4. Guttman F and Murphy OJ, Modern Aspects of Electrochemistry.

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207

ANNEXURE

208

209

ANNEXURE

13.0 Publications and Patents pertaining to Hydrogen

Production through Thermochemical Routes

(I-S & Cu-Cl)

13.1 Publications

1. G. D. Yadav, P.S. Parhad, A. B. Nirukhe and S. B. Kamble. Study of

Hydrogen Generation using Copper and Hydrochloric Acid. Presented at

Chemcon-2008, IIChE Annual congress held in Chandigarh, India

during December 27-30, 2008.

2. D. Parvatalu, A. Bhardwaj and B.N. Prabhu.Technical challenges in

generation of Hydrogen through thermo-chemical processes: ONGC

perspective. Poster paper presented at PETROTECH-2009 held in

Delhi, India during January 11-15, 2009.

3. A. Bhardwaj, D. Parvatalu, and B.N. Prabhu. Closed-loop Thermo-

chemical Cycles for Hydrogen Production: Fuel for Tomorrow. Poster

paper presented PETROTECH-2009 held in Delhi, India during

January 11-15, 2009.

4. A. Bhardwaj, D. Parvatalu, and B.N. Prabhu. Hydrogen Production by

Closed-loop Thermo-chemical Cycles: A Review of S-I Process. Paper

presented at the National Conference on Energy held at Punjab

University, Chandigarh, India during March, 2009.

5. V. Immanuel, K. U. Gokul, S. Sant and A. Shukla. Membrane Electrolysis

of Bunsen Reaction. Presented at CHEMCON-2009, IIChE annual

congress held in Visakhapatnam, India duringDecember 27-30,

2009,

6. D. Parvatalu, A. Bhardwaj and B. N. Prabhu. Electrochemical Routes

Need Better Understanding in Managing Closed- loop Hybrid Thermo-

chemical Hydrogen Generation Cycles. Paper presented at 15th National

convention of Electrochemists held at VIT-University, Vellore, India

during February18-19, 2010.

7. A. Bhardwaj, D. Parvatalu, and B.N. Prabhu. Study of the Alternate

Route in Closed-loop Thermo-chemical Cycles for Hydrogen Production:

fuel for tomorrow. Poster presentation at PETROTECH-2010 held in

Delhi, India during October 31-November 4, 2010.

210

8. A. Bhardwaj, D. Parvatalu, B.N. Prabhu and N.J. Thomas. Future Energy

and Hydrogen. Oral presentation at 17th IORS, held in Mumbai, India

during September 9-10, 2010.

9. D. Parvatalu, Anil Bhardwaj and B.N. Prabhu. Impact of Electrochemical

Routes on thermochemical Hydrogen Generation Technologies. Poster

presentation at ISAEST-9, held in Chennai, India during December 2-

4, 2010.

10. V. Immanuel, K. U. Gokul and A. Shukla. Membrane Electrolysis of

Bunsen Reaction for the Iodine-Sulfur Process for Water Splitting.

Presented at ISAEST-9, held in Chennai, India during December 2-4,

2010.

11. P. K. Sow and A. Shukla. Investigations on Electro-electrodialysis Cell

for Concentration of HIx. Presented at ISAEST-9, held in Chennai, India

during December 2-4, 2010.

12. G. D. Yadav, A. B. Nirukhe and P.S. Parhad. Kinetic Study of Hydrolysis

of Cupric Chloride in Cu-Cl Thermochemical Hydrogen Production.

Presented at CHEMCON-2010, IIChE annual congress held at

Annamalai University, Chidambaram, India during December 27-29,

2010.

13. G. D. Yadav, P.S. Parhad and A. B. Nirukhe. Study of Electrolysis of

Cuprous Chloride. Presented at CHEMCON-2010, IIChE annual

congress held at Annamalai University, Chidambaram during

December 27-29, 2010.

14. P. K. Sow, S. Santand A. Shukla. EIS Studies on Electro-electrodialysis

Cell for Concentration of Hydroiodic Acid. Int J Hydrogen Energy, 2010;

35: 8868–8875.

15. D. Parvatalu, Anil Bhardwaj and B.N. Prabhu. Development of

thermochemical Hydrogen Production by Closed-loop Cycles: ONGC

initiatives. Oral presentation at ICRE-11 held at CNRE, Univ.

Rajasthan, Jaipur, India during January 17-21, 2011.

16. D. Parvatalu, A. Bhardwaj and B.N. Prabhu. Gearing up for Large Scale

Thermochemical Hydrogen Generation Technologies: ONGC Initiatives.

Oral presentation at ICSN 2011 held at Univ. Mumbai, Mumbai, India

during February 14-16, 2011.

17. D. Parvatalu, A. Bhardwaj and B.N. Prabhu. Opportunities and

Challenges Associated with Thermochemical Hydrogen Generation

Technologies: A Perspective in Indian Context. Presented at ICAER

211

2011 held at IIT-Bombay, Mumbai, India during December 9-11,

2011.

18. D. Parvatalu, A. Bhardwaj and B.N. Prabhu. Application of

Electrochemical Technologies in Establishing Closed-loop

Thermochemical Hydrogen Generation Cyclic Processes: ONGC

Initiatives. Oral Presentation at NCE-16 (National Convention of

Electrochemists) held at P.S.G.R.K. College, Coimbatore, India

during December 15-16, 2011.

19. K. Kondamudi, P. Kotari and S. Upadhyayula. Numerical Study of

SulfurtriOxide Decomposition over Complex Catalyst Shapes and Sizes

in S-I Cycle for Hydrogen Production. Presented at Europacat X held at

University of Glasgow, Glasgow, UK during August 28 – September

2, 2011.

20. K. Kondamudi, A.N. Bhaskarwar, S. Upadhyayula, B.N. Prabhu, Anil

Bhardwaj and D. Parvatalu. Kinetic Studies of Sulfuric Acid

Decomposition over Alumina Supported Iron (III) Oxide Catalyst in the SI

Cycle for Hydrogen Production. Presented at ICRE-2011, held in

Jaipur, India during January 17-21, 2011.

21. K. U. Gokul, V. Immanuel, S. Sant and A. Shukla. Membrane Electrolysis

for Bunsen Reaction of S-I Cycle. J. Membr. Sci., 2011, 380, 13-20.

22. V. Immanuel, K. U. Gokul and A. Shukla. Membrane Electrolysis of

Bunsen Reaction in the Iodine – Sulfur Process for Hydrogen Production.

Presented at ICRE-2011 held in Jaipur, India during January 17-21,

2011

23. P. K. Sow and A. Shukla. Electro-Electrodialysis for Concentration of

Hydroidic Acid. Presented at ICRE-2011 held in Jaipur, India during

January 17-21, 2011.

24. K. Kondamudi and S. Upadhyayula. Kinetic Studies of Sulfuric Acid

Decomposition over AL–Fe2O3 Catalyst in the Sulfur-iodine Cycle for

Hydrogen Production. Int. J. Hydrogen Energy, 2012, 37(4), 3586–

3594.

25. P. K. Sow and A. Shukla. A Chronopotentiometry based Identification of

Time-varying Different Transport Resistances of Electro-electrodialysis

Cell used for Concentration of HIx Solution. Int. J. Hydrogen Energy.

2013, 38, 3154-3165

26. P.K. Sow, D. Parvatalu, A. Bhardwaj, B. N. Prabhu and A. N.

Bhaskarwar. Impedance spectroscopic determination of effect of

temperature on the transport resistances of an electro-electrodialysis cell

212

used for concentration of Hydroidic Acid. J. Applied Electrochem, 2012,

43 (11) 31-41.

27. P. K. Sow and A. Shukla. Effect of Asymmetric Variation of Operating

Parameters on EED Cell for HI Concentration in I-S Cycle for Hydrogen

Production. Int. J. Hydrogen Energy, 2012, 37(19), 13958-13970.

28. V. Immanuel, D. Parvatalu, A. Bhardwaj, B. N. Prabhu, A. N.

Bhaskarwar and A. Shukla. Properties of Nafion 117 in Highly Acidic

Environment of Bunsen Reaction of I-S Cycle. J. Membr. Sci., 2012,

409-410, 137-144.

29. V. Immanuel and A. Shukla, “Effect of Operating Variables on

Performance of Membrane Electrolysis Cell for Carrying Out Bunsen

reaction of I-S Cycle” Int. J. Hydrogen Energy, 2012, 37, 4829-4842.

30. P. K. Sow and A. Shukla. Electro-electrodialysis for Concentration of

Hydroidic Acid. Int. J. Hydrogen Energy, 2012, 37, 3931-3937.

31. V. Immanuel, K. U. Gokul and A. Shukla. Membrane Electrolysis of

Bunsen Reaction in the Iodine-Sulfur Process for Hydrogen Production.

Int. J. Hydrogen Energy, 2012, 37, 3595-3601.

32. P. K. Sow and A. Shukla. A Chronopotentiometry based Identification of

Time-varying Different Transport Resistances of Electro-electrodialysis

Cell Used for Concentration of HIx Solution. Int. J. Hydrogen Energy,

2013, 38(8), 3154-3165.

33. D. Parvatalu, S. Banerjee and B.N. Prabhu. Envisaged Technical

Barriers in Converting Electrochemical Solutions to Hybrid-

Thermochemical Technologies: ONGC Perspective. Paper presented at

ISAEST-10held in Chennai, India during January 28-30, 2013.

34. A.B. Nirukhe, P.S. Parhad, A. Bhardwaj, D. Parvatalu and G. D. Yadav.

Hydrogen Production by Non-Catalytic Decomposition of Hydroidic Acid.

Paper accepted for presentation at the International Conference on

Advances in Chemical engineering (ICACE-2013)to be held at NIT,

Raipur, India during March, 8-9, 2013.

35. S. Kamini, S. Banerjee, D. Parvatalu and B.N. Prabhu. Hydrogen

Production by Thermochemical Iodine-Sulfur Cycle: Process Simulation

Studies of Bunsen Section. Paper presented at the International

Conference on Advances in Chemical engineering (ICACE-

2013)held at NIT, Raipur, India during April 5-6, 2013.

36. K. Kondamudi and S. Upadhyayula, “Decomposition of Sulfuric Acid

over Mixed Metallic Oxides - A Comparative Study for Oxygen Evolving

213

Step in S-I Cycle for Hydrogen Production”, EUROPACAT XI

Conference, LYON, France, September 1-6, 2013.

37. D. Parvatalu and B.N. Prabhu. Material Issues Dictate Hydrogen

Generation by Thermochemical Water Splitting Technologies: ONGC

Energy Center Perspective. Presented at CORCON-2013, New Delhi.

38. D. Parvatalu, S. Banerjee and B.N. Prabhu. Recent Developments in

Hydrogen Generation using Iodine- Sulfur Thermochemical Water

Splitting Cycle: ONGC Energy Center efforts, PETROTECH-2014held in

Delhi, India during January 12-15, 2014.

39. D. Parvatalu. Development of Thermochemical Hydrogen Generation

Technologies using Water Splitting Processes: ONGC Energy Center

Perspective. Invited lecture at National workshop on “Fuel Cell

Technology: Basic science to Application” held at MANIT, Bhopal

during March 24-25, 2014

40. D. Parvatalu. Hydrogen is the Key to Success of Renewable Energy

Campaign: ONGC Energy Centre perspective. Invited talk at the

National Seminar during 17-18th November 2014 at Univ. Kerala,

Trivandrum organized by Indian Association for Hydrogen Energy and

Advanced Materials

41. Kamini Shivakumar, S. Banerjee and D. Parvatalu. Simulation studies

on HI Decomposition in Thermochemical Iodine-Sulfur Cycle. Paper

presented at CHEMCON-2014, the 67th Annual Session of the Indian

Institute of Chemical Engineers to be held at Punjab University,

Chandigarh, from 27th – 30th December, 2014.

42. D. Parvatalu, An Overview of Material Requirements for Copper-Chlorine

Thermochemical Cycle: ONGC Energy Centre Perspective. Paper

published in Society for Materials Chemistry Quarterly Bulletin

issued by BARC, 2014

43. D. Parvatalu. Development of Closed-loop Thermochemical Water

splitting Processes for Hydrogen Generation: ONGC Energy Centre

Initiatives. Presentation at 3rd International Conference on Hydrogen

and Fuel Cell during 7-9 December 2014 at Udaipur.

44. D. Parvatalu. Role of Catalysts in the Development of the Iodine-

Sulfur and Copper-Chlorine Thermochemical Hydrogen Generation

Technologies. Presented at 22nd National Symposium on Catalysis

(CATSYMP 22) during 7-9.01.2015 at CSMCRI Bhavnager.

45. N. Sathaiyan, V. Nandakumar, G. Sozhan, J. Ghandhiba Packiaraj, E.T.

Devakumar, D. Parvatalu, Anil Bhardwaj and B.N. Prabhu. Hydrogen

214

Generation through Cuprous Chloride-Hydrochloric Acid

Electrolysis. International Journal of Energy and Power Engineering, 27

January 2015. [Pages 15-22]

13.2 Details of Patents

Sl.

No.

Patent title Institutions Patent Details

1 Hydrogen Production Method by

Multi-Step Copper-Chlorine

Thermochemical Cycle

OEC and ICT,

Mumbai

National and

International*

2 Electrochemical Cell Used for the

Production of Copper Using Cu-Cl

Thermochemical Cycle

OEC and ICT,

Mumbai

National and

International*

3 Effect of Operating Parameters on

the Performance of

Electrochemical Cell in Copper-

Chlorine Cycle

OEC and ICT,

Mumbai

National and

International*

4 High Performance Supported

Metallic/Mixed Metallic Catalyst

for Sulfuric Acid Decomposition in

Sulfur-Iodine (SI) Cycle for

Hydrogen Production

OEC and IIT,

Delhi

National*

5 Process for Catalytic

Decomposition of Sulfuric Acid

over High Performance Supported

Metallic/Mixed Metallic Catalyst in

SI Cycle

OEC and IIT,

Delhi

National*

6 Highly active supported bimetallic

(Ni-Pt) catalyst for hydrogen

iodide (HI) decomposition and

synthesis procedure thereof

OEC and IIT,

Delhi

National*

7 Vanadia supported Pt catalyst

and use thereof for hydrogen-

iodide decomposition in sulfur-

iodine (I-S) cycle for hydrogen

production.

OEC and IIT,

Delhi

National*

The US and Japan patents on “Hydrogen Production Method by Multi-Step

Copper - Chlorine Thermochemical Cycle” have been granted.

*********