Reversible Liquid Carriers for an integrated Production, Storage and Delivery of

HydrogenBernie Toseland and Alan Cooper

Air Products and Chemicals, Inc.

May 21, 2009

# pd_38_toseland

This presentation does not contain any proprietary, confidential, or otherwise restricted information

2

Overview

• Start: Date 8/2005• Team Kickoff 10/2008• Project end March 2011• 49% Complete

• Barriers addressedE. Solid and Liquid Carrier TransportA. Hydrogen/Carrier and Infrastructure 

Options AnalysisF. Hydrogen Delivery Infrastructure Cost

• Total project $4,131,138– DOE share (75%)

– Contractor share (25%)

• Funding received in FY08: $1,971,670

• Funding for FY09 

Timeline

Budget

Barriers

• Pacific Northwest National Laboratory/Battelle

• United Technologies Research Center (UTRC)

• BMW Group

Partners

Approach

REFUELING STATION

ICE /Fuel CellHeat ExchangeReactor +

Catalyst

LiquidStorage

LQ*H2

PRODUCTION & DISTRIBUTION

DischargedFuel

Heat

Heat

Heat

LQ := liquid carrier

LQ

LQ*H2

LQ

H2

Electricity H2

Specific Project Approach

• Mobile Reactor initial focus– Rationale: This is the most constrained challenge. Data gathered will be applicable to all delivery modes, FC, ICE and forecourt, since reaction heat will be supplied by high temperature fluid stream for all reactor types. 

• N‐Ethyl Carbazole, while not suitable for commercial use is suitable as a test fluid.– Model compound allows reactor characterization, and economic studies but is not final material.

– Evaluate economic potential using N‐ethylcarbazole as a model compound

• Modeling will be used to simulate, optimize and evaluate each mode of hydrogen delivery

Collaboration• BMW

– Model integration of ICE and automobile– Testing prototypes

• Evaluate performance• Provide operational parameters

• UTRC– Model integration of FC and reactor.

• Forecourt• Automobile

• PNNL– Design of microreactors– Fabrication of prototype(s)

• AP– Testing of single microchannel reactors and packing for forecourt reactors– Providing materials– Testing prototypes (ICE)– Project Coordination

6

Technical Accomplishments

Microchannel Reactor Results

Single-tube microchannel reactors performed well– Stable catalyst coating method was established.– Reactor diameters from 2.55-0.5mm were demonstrated. (5 mm for

particles) – Single-pass conversions as high as 90% achieved.– Temperatures from 190-2500C were achieved.

Catalyst Feed Rate H2 Flow Conversion(ml/min.) (sccm) (% available H2)

Pt 0.1 52 800.4 193 741 421 65

Pd 0.1 23 350.4 50 201 75 12

Pd (particles) 0.1 59 911 458 71

Typical Results 2500C

Technical Accomplishments

Efficiencies of Microchannel ReactorsPd Catalyst microchannel Reactor shows low catalyst efficiency and little effect of reactor length.

Pt Catalyst microchannel Reactor shows low catalyst efficiency and little effect of reactor length.

0

50

100

150

200

250

300

350

400

450

220 230 240 250 260

Hyd

roge

n Fl

ow, s

ccm

Temperature, 0C

Expt. 15 mg Pt

Sim. 0.195 mg Pt

Expt. 7.5 mg Pt

Sim. 0.0975 mg Pt

Catalyst efficiency is 1.3% for both cases

05

101520253035404550556065

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8

Hyd

roge

n Fl

ow, s

ccm

Catalyst , Mg. Pd

Rate Calculated using Pd KineticsMeasured Rate ‐4 mg PdMeasure Rated ‐2 mg Pd

MeasuredRate4 mg. Pd

Measured rate2 mg. PdEfficiency‐ 15%

Efficiency =11%Calculated by comparingactual catalyst amountto that calculated from kinetics

What is Primary cause of low efficiency?

Technical Accomplishments

Kinetics Modeling• Dehydrogenation modeled 

adequately as three reactions in series.

• Batch experiments using slurry catalyst (small particles to eliminate mass transfer resistances) used for primary data.

• Activity of other catalyst forms done on the basis of the weight of the metal. (We expect some reduced efficiency when used in a thin film (typically 50% reduction based on APCI monolith experience))

• Kinetic expressions used in process models and to evaluate reactor performance or strategy. E.g., for Pd takes 40% more metal to go from 90 to 95 % conversion.  0

20

40

60

80

100

0 0.005 0.01 0.015 0.02

Con

vers

ion,

%

.

Pd vs. Pt 2500C and 0.25 ml/min.

Pd Catalyst

Pt catalyst

Weight of Metal, gms.

225

230

235

240

245

250

255

0200400600800100012001400160018002000

0 100 200 300 400

Tempe

rature (C

)

H2flo

w (sccm)

Time (min)

Fit

Data

Temp

Typical Fit to Slurry Data

Technical Accomplishment

CFD analysis of microchannel reactor flowRe-analysis of tubular flow pattern in microchannel

CFD Analysis of Liquid Distribution in Annular Microchannel Reactor

Region shown where liquid volume fraction

1

N‐ethylcarbazole conc. max = 0.01

Conclusion: Extremely low amount of liquid at Catalyst Surface limits catalyst efficiency 

Profile of liquid along a line  5 μm away from the Catalyst Surface (annular outer wall)

Liquid Volume Fraction at catalyst surface decrease dramatically along Tube LengthN‐ethylcarbazole conc.

min= 0.0

Increased calculation precision shoes liquid breaks up into droplets

Microchannel Dehydrogenation ReactorTechnical Approach

• Address the issue of low liquid volume at catalyst surface by :– Segregating gas from liquid within the reactor

– Keeping the catalyst wet and increasing liquid residence time

• Improve heat transfer to support endothermic reaction– Using laminate architecture

• Scale‐up by numbering up channelsHxr Fluid InHxr Fluid Out

ΔPflow ΔPcap

O ︵0.1 mm ︶

Catalytic wick

H2

Liquid HydrogenOrganic Carrier

(LOHC)Dehydrogenated liquid

H2 H2 H2

LOHC

Microchannel Dehydrogenation ReactorTechnical Progress and Path Forward

• Single Channel Microwick Reactor– Approx. 5 cm x 6 cm footprint– 1‐3 mm deep– Sapphire window to observe phase segregation– Heated with microchannels from below– Targets

• 1 mg Pt/cm2• ~60 We equivalent power (0.06 g H2/min)

• Initial results– Excellent gas‐liquid separation at room 

temperature– Discovered unexpected phenomena at > 100ºC

• ‘Free liquid’ forms stable liquid droplets• Liquid droplets become entrained in gas flow• Reduces wicking flow capacity

– 17% target catalyst loading– 2% H2 productivity

Single channel catalytic wick

LOHC drops

Flow direction

T = 25 °C

T = 210 °C

Technical AccomplishmentsIntegration ICE and Liquid Carriers

Defuel

ICE

Exhaust Gas

Option:Coolant

LOHC Core System Boundary

H2

Storage Dehydrogenation

ΔpExhaust

Refuel

Defuel

ICE

Exhaust Gas

Option:Coolant

LOHC Core System Boundary

H2

Storage Dehydrogenation

ΔpExhaust

Refuel

LOHC‐SystemSystem Objectives

Combining operating characteristics of ICEe.g. Exhaust gas conditions

H2‐consumption

Exhaust he

at

Texhaust

Performance Requirementse.g. Transient Run‐up of Reactor

Initial modeling has defined feasible operating points depending upon characteristic of liquid carriers

Steady‐State Operation of ReactorTDehydrogenation vs. ΔH

steady‐state operation feasible !

QExhaust > QDehydrogenation

TDehyd 3

ΔH3

TDehyd 2

ΔH2

TDehyd, 1

ΔH1

indifferent

QExhaust ~ QDehydrogenation

additional heat source required !

QExhaust < QDehydrogenation

< << <

010203040506070

0 2 4 6 8 10

Heat‐Flow[kW]

010203040506070

0 2 4 6 8 10

Heat‐Flow

[kW]

010203040506070

0 2 4 6 8 10

Heat‐Flow

[kW]

Exhaust

Reactor

Exhaust

Reactor

Exhaust

Reactor

H2‐Flow [kg/h] H2‐Flow [kg/h] H2‐Flow [kg/h]

steady‐state operation feasible !

QExhaust > QDehydrogenation

TDehyd 3

ΔH3

TDehyd 2

ΔH2

TDehyd, 1

ΔH1

indifferent

QExhaust ~ QDehydrogenation

additional heat source required !

QExhaust < QDehydrogenation

< << <

010203040506070

0 2 4 6 8 10

Heat‐Flow[kW]

010203040506070

0 2 4 6 8 10

Heat‐Flow

[kW]

010203040506070

0 2 4 6 8 10

Heat‐Flow

[kW]

Exhaust

Reactor

Exhaust

Reactor

Exhaust

Reactor

H2‐Flow [kg/h] H2‐Flow [kg/h] H2‐Flow [kg/h]

H2-F

eedf

low

Engi

neLo

ad, e

ff.

LOHC

-Rea

ctor

-Tem

p.<

Exha

ust-T

emp.

Tambient

Vehicle Parking Vehicle Driving

Exhaust‐Temp.

ICE  Load

H2 ‐Strom 

Reactor‐Temp.

TSt

atio

när.

TDe

hydr

gen.

LOHC‐PumpON

0 3 s 2‐3 min

H2-F

eedf

low

Engi

neLo

ad, e

ff.

LOHC

-Rea

ctor

-Tem

p.<

Exha

ust-T

emp.

Tambient

Vehicle Parking Vehicle Driving

Exhaust‐Temp.

ICE  Load

H2 ‐Strom 

Reactor‐Temp.

TSt

atio

när.

TDe

hydr

gen.

LOHC‐PumpON

0 3 s 2‐3 min

Tech Accomplishments/RelevanceEstimation of full‐size core reactor:• Target: 10 kg H2/h , 60 kW thermal• Heat transfer limiting reactor size

– Current reaction rate (no mass transfer issues) support  this– Case 1: Demonstrated in commercial‐ready devices – Case 2: Laboratory demonstrated

500 [m2 / m3] 1000 [m2 / m3]

60 [kW] 60 [kW]

Reactor Volume 2,8 [l] 1,4 [l]

Heat Exchange Area 1,4 [m2] 1,4 [m2]

Reactor Mass 11 [kg] 6 [kg]

Reactor Volume 0,5 [l] 0,2 [l]

Heat Exchange Area 0,24 [m2] 0,24 [m2]

Reactor Mass 2 [kg] 1 [kg]Oil

heat

ed

Demonstrated Laboratory

Gas

hea

ted

Conclusion:Reactor size estimations should be suitable for use in automobile

VolumeReactorAreaExchangeHeatHeat transfer limit

14

Leveraging UTRC Fuel Cell modeling (gPROMS), system models are being constructed to evaluate on‐board performance and apply waste heat sources to drive the dehydrogenation process at the forecourt.

Fuel Cell / Forecourt Integration Modeling

• On‐board– Extend Argonne National Lab on‐board analysis: 

modify configuration, incorporate PNNL reactor performance, conduct trade‐off studies (weight, volume, kinetics, efficiency).

• Forecourt baseline configuration– Burn H2 for dehydrogenation process

“System Level Analysis of Hydrogen Storage Options”,Ahluwalia, R.K. et al., 2007 DOE H2 Program Review,May 2007.

Reactor

Forecourt

Combustor

Working fluid

100% H2

100 + x%

x%

Q1 Q2

Th

Tank

Recuperator

LOHCH

LOHCDH

Air

Exhaust

15

Forecourt/FC Modeling

• Forecourt modeling: Several system configurations for hydrogen generation using the liquid carrier are being modeled leveraging existing models to improve heat utilization efficiency for the overall plant.

2

2

2

2:R32:R22:R1

HDCHCBHBA

+→+→+→

⎟⎟⎠

⎞⎜⎜⎝

⎛⎟⎟⎠

⎞⎜⎜⎝

⎛−=TT

RTE

kk ref

ref

iaoii 1exp ,,

Tref =  400 K

N

C2H5

N

C2H5

N

C2H5

N

C2H5

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 100 200 300 400

liqu

id m

ole

fract

ions

Time [min]

230

232

234

236

238

240

242

244

246

248

250

252

T [C]

A (left) B (left) C (left) D (left) T (right)

-20

-15

-10

-5

0

5

10

15

20

0 200 400 600 800 1000

Temperature [K]

Kca

l/mol

e

R1 dHR1 dGR2 dHR2 dGR3 dHR3 dG

ΔH, ΔG

• Reactor kinetics– Air Products model incorporated into UTRC gPROMS models

Implementation validated

Summary

• Microchannel reactors – Dehydrogenation successful over a variety of conditions– Low catalyst efficiency was traced tothe high gas flow rate.– Experimental work to separate gas flow and increase liquid 

contact is underway.• Modeling

– Forecourt/FC: We have begun building system models • to evaluate on‐board performance and • the dehydrogenation process at the forecourt.

– Initial modeling of ICE• determined that the reactor size should be feasible for an automobile• defined stable operating point depending upon the characteristics of the carrier fluid

Future Work

Project Overview• Reactor Testing

– Test novel catalyst forms (foams) for forecourt reactor – Improve the gas-liquid separation in a Microwick Reactor

• Modeling– Incorporate reactor models into Fuel Cell/ Forecourt

Modeling and perform trade-off analysis– Continue high-level system evaluation for ICE by adding

necessary components with the goal of evaluating dynamic system characteristics

• Supply– Provide hydrogenated feed for all partners– Scale up hydrogenation process

Future Work –Microchannel Reactor Development Milestones

Phase II

Phase I

2009

JvW, Oct 29 2008

2010`08

Microchannel

Oil heated

100 W

06/09PoP I ready

Microchannel

Oil heated

100 W

09/09PoP II ready

Microchannel

Gas heated

100 W

11/09PoP III ready

03/10Prototype ready

Microchannel

tbd.

1000 W

06/09GO / NO GO decision

Proof of Principles (P.o.P.s) Proof of Concept