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Polysulfide reduction using sulfate-reducing bacteria in a photocatalytic hydrogen generation system
Yui Takahashi1, Koichi Suto, Chihiro Inoue
1Department of Environmental Studies, Graduate School of Environmental Studies, Tohoku University, 6-6-20 Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan.
Journal of Bioscience and Bioengineering
|October 22, 2008
Summary
Sulfate-reducing bacteria (SRB) can regenerate hydrogen sulfide from polysulfides, enabling cyclic photocatalytic hydrogen generation. This biological regeneration process shows promise for sustainable hydrogen production using waste biomass.
Area of Science:
- Biotechnology
- Environmental Science
- Chemical Engineering
Background:
- Photocatalytic hydrogen generation offers a sustainable energy pathway.
- Cyclic operation requires efficient regeneration of hydrogen sulfide from polysulfide intermediates.
- Current regeneration methods may be energy-intensive or inefficient.
Purpose of the Study:
- To investigate the feasibility of using sulfate-reducing bacteria (SRB) for hydrogen sulfide regeneration in a photocatalytic system.
- To assess the impact of polysulfide concentration on SRB activity and hydrogen sulfide production.
- To explore the potential of utilizing waste biomass as an electron donor for SRB.
Main Methods:
- Batch cultivation of naturally sourced SRB using polysulfide-containing media.
- Analysis of hydrogen sulfide production from various polysulfide sources.
- Evaluation of SRB enrichment culture T2 for hydrogen sulfide generation efficiency.
- Assessment of organic matter utilization by SRB as electron donors.
Main Results:
- SRB successfully produced hydrogen sulfide from multiple polysulfide sources, including those from photocatalytic reactions.
- Hydrogen sulfide production rate and lag phase were influenced by initial polysulfide concentration.
- High polysulfide concentrations inhibited SRB activity.
- SRB enrichment culture T2 demonstrated high hydrogen sulfide production rates and utilized diverse organic matter.
Conclusions:
- Sulfate-reducing bacteria are effective in regenerating hydrogen sulfide, facilitating cyclic photocatalytic hydrogen generation.
- The process is sensitive to polysulfide concentration, with optimal ranges identified.
- Waste biomass sources like sewage sludge and garbage are potential low-cost electron donors for SRB in hydrogen generation systems.
- An SRB-based hydrogen generation system is deemed feasible, offering a sustainable approach to hydrogen production.
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