General Update

Bojan Tamburic

Investigating the pO2/pH2 electrode

Max pO2 = 48.3%

Flush with He

Stop He flushing, min pO2 = 8.2%

Switch probe polarity to pH2

Sparge with H2 ≈ 30ml/min

Stop H2 sparging, pH2 = 10.1%

Stop He flushing, min pH2 = 7.3%

Natural rise up to pH2 = 23.0%

Switch probe polarity to pO2

Flush with He

Suspected temperature variations

pO2

pH2

Investigating the pO2/pH2 electrode

pO2

pH2

T stabilisation

Flush with He

pO2 recovery

Flush with He

pO2 recovery

Switch to pH2

Probe instability

Sparge H2

Sparge H2

Transfer report outline

Literature review• H2 production

• Photosynthetic H2 production• Parameters affecting algal growth• Parameters affecting H2 production• Photobioreactor systems

Experimental Method• Growing C.reinhardtii• Measuring growth and H2 production kinetics• Sartorius reactor: calibration and improvement• Sulphur deprivation procedure• Flat plate bioreactor design

Results• C.reinhardtii growth in the column reactors• Growth kinetics in the Sartorius reactor• Stirred-tank batch reactor H2 production results• Sartorius H2 production results

Research paper summary

Review of resultsHYSYDAYS Turin paperRewrite?

Photobioreactor design & Algal comparative studyLocked up with WHEC Essen abstractsRelease?

Good at:Controlling light intensity, agitation, spargingMeasuring OD, pH, pO2

Not good at:Measuring H2

Growth kinetics experiment

Growth kinetics experiment

Algal strain = CC-124 Temperature = 25°C

Agitation = 40%Light intensity = 20%

Algal strain = CC-124 under dilution Temperature = 20°C

Agitation = 50%Light intensity = 44%

K = 0.345r = 0.0720t0 = 29.3

K = 0.432 r = 0.0523t0 = 35.6

)tr(t 0e1KOD(t)

Growth kinetics experiment

CC-124 growthOD as a function of time at various light

intensities

Determine optimal ODOD as a function of light intensity

)tr(t 0e1KOD(t)

Growth kinetics experiment

CC-124 growthOD as a function of time at various

agitation rates

CC-124 growthOD as a function of time with and

without CO2 sparging

)tr(t 0e1KOD(t)

WHEC 2010 abstracts

Some unicellular green algae have the ability to photosynthetically produce molecular hydrogen using sunlight and water. This renewable, carbon-neutral process has the additional benefit of sequestering carbon dioxide during the algal growth phase. The main costs associated with this process result from building and operating a photobioreactor system. The challenge is to design an innovative and cost effective photobioreactor that meets the requirements of algal growth and sustainable hydrogen production. We document the details of a novel 1 litre vertical flat-plate photobioreactor that has been designed to accommodate green algal hydrogen production at the laboratory scale. Coherent, non-heating illumination is provided by a panel of cool white LEDs. The reactor body consists of two compartments constructed from transparent polycarbonate sheets. The primary compartment holds the algal culture, which is agitated by means of a recirculating gas flow. A secondary compartment is filled with water and used to control the temperature and wavelength of the system. The reactor is fitted with instruments that monitor the pH, pO2, temperature and optical density of the culture. A membrane inlet mass spectrometry system has been developed for hydrogen collection and in-situ monitoring. The reactor is fully autoclaveable and the possibility of hydrogen leaks has been minimised. The modular nature of the reactor allows efficient cleaning and maintenance.

Some unicellular green algae, such as Chlamydomonas, have the ability to photosynthetically produce molecular hydrogen under anaerobic conditions. They offer a biological route to renewable, carbon-neutral hydrogen production from two of nature’s most plentiful resources – sunlight and water. This process provides the additional benefit of carbon dioxide sequestration and the option of deriving valuable products from algal biomass. The aim of this study is to analyse the hydrogen production rates of green algae, focusing on multiple strains of Chlamydomonas, including several laboratory wild types, marine species and diverse mutant strains. Hydrogen production is initially screened by water displacement measurement in a 300ml batch photobioreactor with the aim of conducting a preliminary comparison and identifying promising strains for further study. Selected strains are analysed in a 3l tubular flow photobioreactor featuring a large surface-to-volume ratio and excellent light penetration through the culture. Key parameters of the hydrogen production process are continuously monitored and controlled; these include pH, pO2, optical density, temperature, agitation and light intensity. A membrane inlet mass spectrometry system has been developed for hydrogen collection and in-situ monitoring.

Design of a novel flat-plate photobioreactor system for green algal hydrogen production

B. Tamburic, F.W. Zemichael, G.C. Maitland, K. Hellgardt

A comparative study of hydrogen production by selected Chlamydomonas strains

B. Tamburic, F.W. Zemichael, S. Burgess, M. Boehm,K. Hellgardt, P.J. Nixon

Other issues

Flat plate reactorBase designPumpsMIMS system

HPLCDevelop organic acid methodologyMake standardsPurchase RI detector to measure ethanol

Filtration systemSet it up and test it

Purchase Hydrogen peroxide

Experimental Update

Palang

0 20 40 60 80 100 120 140 160

-10

-9

-8

-7

-6

-5

-4

-3

-2

-1

0

On Vitreous Carbon

-0.3V -0.4V -0.5V -0.6V -0.7V

t (s)

j (A/

m2)

0 2 4 6 8 10 12 14 16

-10

-8

-6

-4

-2

0

2

4

6

8

10

Grew on WO3 at -0.2V for 15s

t (s)

j (A/

m2)

0.2 0.4 0.6 0.8 1 1.2 1.4 1.6

-0.3

-0.2

-0.1

0

0.1

0.2

0.3

WO3-IrOx in 1M H2SO4

Bare WO3 Grew at -0.2V for 5s Grew at -0.2V for 15s

E (V) vs. SCE

j (A/

m2)

Experimental Update

Chris Carver

0 1 2 3 4 5 6 70

200

400

600

800

1000

1200TnO Voltage-Current Response

no membrane, single channel 100rpm

membrane, dual channel 200rpm

Voltage (V)

Curr

ent (

mA)

Model Update

Zachary Ulissi

Justification of Tafel Kinetics

Low Overpotential High Overpotential

Justification of Tafel Kinetics

Si-Doped Fe2O3, with and without Co-Phosphate catalyst

Gratzel Lab Si-Doped Fe2O3 films

Gratzel Lab Si-Doped Fe2O3 film supported on WO3 Substrate

Justification of Tafel Kinetics

Justification of Tafel Kinetics

Bubble Formation

Semiconductor transport important