Anaerobic Hydrogen Production

Anaerobic hydrogen production proceeds from photofermentation as well as without the presence of light. Anaerobic bacteria use organic substances as the sole source of electrons and energy, converting them into hydrogen. 

The reactions involved in hydrogen production (Eqs. 6.3 and 6.4) are rapid and these processes do not require solar radiation, making them useful for treating large quantities of wastewater by using a large fermenter. 

Since they cannot utilize light energy, the decomposition of organic substrates is incomplete. Further decomposition of the acetic acid is not possible under anaerobic conditions. Nevertheless, these reactions are still suitable for the initial steps of wastewater treatment and hydrogen production, followed by further waste treatment stages. 

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Schematic of ZECA process the anaerobic hydrogen production and fuel cell system. Material flows are idealized to predominant components.

Chen, C. C., Lin, C. Y., and Lin, M. C. 2002. Acid-base enrichment enhances anaerobic hydrogen production process. Appl. Microbiol. Biotechnol., 58, 224-228. 

The iron-hydrogenase of Thermotoga maritima utilizes ferredoxin and NADH synergistically a new perspective on anaerobic hydrogen production. 

Biofuel generation from sweet sorghum Fermentative hydrogen production and anaerobic digestion of the remaining biomass. Biores. Technol. 99 (1), 110-119. 

The formation of hydrogen is accompanied with VFAs or solvent production during an anaerobic digestion process. Therefore, the distribution of VFA concentrations and their finctions is a usefiil indicator for monitoring hydrogen production. Fig. 3 shows the variations in alcohol and VFAs. Most of the VFAs were analyzed as acetate and butyrate, and most of the alcohols were analyzed as ethanol. The propionate concentration was below the analytical limit. It indicates that the anaerobic pathway in the reactor is not propionic-type fermentation but but5nrate-type fermentation. Clostridium butyricum is considered to be the dominant... 

S. Kawamura, J. G. O Neil, J. F. Wilkinson (1983) Hydrogen production by methylotrophs under anaerobic conditions. J. Ferment. Technol., 61 151-156... 

The majority of microbial hydrogen production is driven by the anaerobic metabolism of pyruvate, formed during the catabolism of various substrates. The breakdown of pyruvate is catalyzed by one of two enzyme systems ... 

Long-term aim of our project is the construction of a biomolecular device for hydrogen production in combination with light-driven water-splitting as it occurs in the natural process of photosynthesis in plants. Such a semiartificial device should combine the best suited components found in various native systems which - up to now - cannot be found in an individual native system due to incompatibilities and/or different origin (pro- and eukaryotic, meso- and thermophilic, aerobic - anaerobic environment). Advantage of such a system is... 

In some anaerobic microorganisms, production of hydrogen serves as a mechanism to get rid of excess reducing potential, while in many others hydrogen consumption is coupled... 

Hydrogenase was named by Stephenson and Stickland in 1931, discovered in their experiments using anaerobic colon bacterium Escherichia Coli that evolved hydrogen [144-146]. Hydrogenase enzymes are metalloproteins that contain sulfur and nickel and/or iron [147]. To date over 80 hydrogenase enzymes have been identified. These enzymes reversibly catalyze hydrogen production/uptake reactions ... 

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