Reviewed by Holden Ranz

ChE 391: Independent Study

Advised by Professor Piergiovanni

Original Interest

Alternative energy Algae

What can be done to make

algae fuel more sustainable?

Biodiesel processing

generates residual glycerol

Certain unicellular organisms

can produce H2

○ Glycerol be used as substrate

for H2 production?

Fermentative Hydrogen

Dark Fermentation

glycerol

1,3-propanediol

+ hydrogen

Biological limitations

Require carbohydrates

Low yields of energy

Specific T, P, pH requirementsEnterobacter

Clostridium

Fermentative Hydrogen

Photofermentation

photosynthetic bacteria

(purple non-sulfur)Rhodopseudomonas Rhodobacter

Biophotolysis

Light-driven decomposition

of water

Direct Biophotolysis

green algae, cyanobacteria

Advantages:

○ High solar energy conversion

Disadvantages:

○ O2 inhibition

Biophotolysis

Indirect Biophotolysis

cyanobacteria

Advantages:

○ Able to fix N2 from atmosphere

Disadvantages:

○ Lower efficiency than direct

Biohydrogen Downfalls

Low yields

Inhibition of hydrogen production

Requires low levels of H2, O2

Gas separation needed

Biological sensitivity

Metabolic pathways for alcohol

formation

Evolved Interest

Hydrogenase enzymes Catalyzes redox: 2H+

H2

Can hydrogenases be used as electrocatalysts for fuel cell applications?

Surprising

amount of

development in

FC technology

and enzymes!

Hydrogenase Enzymes

Serve function that is closely related to needs for technological systems

Can be used in multiple alternative energy applications

Active Site

Nature uses nickel, iron, and sulfur for H2production/activation Fe-Fe (Clostridium)

Ni-Fe

Hydrophobic channels

Enzyme Electrodes

Anodes

Cathodes

Stability/structure

Adsorption to carbon

support

○ PGE, GCE, carbon felt

Encapsulation in polymeric

porous gels

○ Si-O-Si network

Progress of Enzyme Electrodes

CO poisoning not an issue

Energy conversion of enzyme electrode comparable to noble metal based commercial fuel electrode

Alternative for fuel cells and electrolysis

Continuing Research

Improving electrode

stability and activity

Doping of sol-gel

○ Methyl viologen

○ Carbon nanotubes

Integration of

photosystem

Porphyrin - TiO2

colloidal system

References

Adhikari, Sushil, Sandun Fernando, and Agus Haryanto. "Hydrogen Production from Glycerin by Steam Reforming over Nickel Catalysts." Renewable Energy 33 (2008): 1097-100. Web.

Demirbas, Ayhan. "Progress and Recent Trends in Biofuels." Progress in Energy and Combustion Science 33 (2007): 1-18. Web.

Ito, Takeshi, Yutaka Nakashimada, Koichiro Senba, Tomoaki Matsui, and NaomichiNishio.

"Hydrogen and Ethanol Production from Glycerol-Containing Wastes Discharged after Biodiesel Manufacturing Process." Journal of Bioscience and Bioengineering 100.3 (2005): 260-65. Web.

Liu, Fei, and Baishan Fang. "Optimization of Bio-hydrogen Production from Biodiesel Wastes by Klebsiella Pneumoniae." Biotechnology Journal 2 (2007): 374-80. Web.

Yang, Zhiman, Rongbo Guo, Xiaohui Xu, Xiaolei Fan, and Shengjun Luo. "Fermentative Hydrogen Production from Lipid-extracted Microalgal Biomass Residues." Applied Energy 88.10 (2011): 3468-472. Print.

Yu, J., and P. Takahashi. "Biophotolysis-based Hydrogen Production by Cyanobacteriaand Green Microalgae." Http://www.formatex.org/microbio/pdf/Pages79-89.pdf. 2007. Web. 19 Feb. 2012.

"Improvement of Fermentative Hydrogen Production: Various Approaches." Web.

http://www.fao.org/docrep/w7241e/w7241e06.htm

http://www.bw2e.com/images/dia2.gif

http://www.hielscher.com/image/biodiesel_process_chart_p0500.gif

http://www.theprofessionalgroup.com/Enterobacter.html

http://world.edu/wp-content/uploads/2011/12/cyanobacteria1.jpg

http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/wimsmall/green.html

Questions?