Sulfide-Driven Microbial Electrosynthesis

Journal Article · Mon Dec 31 23:00:00 EST 2012 · Environmental Science and Technology

DOI:https://doi.org/10.1021/es303837j· OSTI ID:1211138

Gong, YM; Ebrahim, A; Feist, AM; Embree, M; Zhang, T; Lovley, D; Zengler, K

Microbial electrosynthesis, the conversion of carbon dioxide to organic molecules using electricity, has recently been demonstrated for acetogenic microorganisms, such as Sporomusa ovata. The energy for reduction of carbon dioxide originates from the hydrolysis of water on the anode, requiring a sufficiently low potential. Here we evaluate the use of sulfide as an electron source for microbial electrosynthesis. Abiotically oxidation of sulfide on the anode yields two electrons. The oxidation product, elemental sulfur, can be further oxidized to sulfate by Desulfobulbus propionicus, generating six additional electrons in the process. The eight electrons generated from the combined abiotic and biotic steps were used to reduce carbon dioxide to acetate on a graphite cathode by Sporomusa ovata at a rate of 24.8 mmol/day.m(2). Using a strain of Desulfuromonas as biocatalyst on the anode resulted in an acetate production rate of 49.9 mmol/day.m(2), with a Coulombic efficiency of over 90%. These results demonstrate that sulfide can serve effectively as an alternative electron donor for microbial electrosynthesis.

• Sponsoring Organization: USDOE Advanced Research Projects Agency - Energy (ARPA-E)
• DOE Contract Number: AR0000087; AR0000159
• OSTI ID: 1211138
• Journal Information: Environmental Science and Technology, Journal Name: Environmental Science and Technology Journal Issue: 1 Vol. 47; ISSN 0013-936X
• Country of Publication: United States
• Language: English