title: Carbon dioxide reduction by mixed and pure cultures in microbial electrosynthesis using an assembly of graphite felt and stainless steel as a cathode.
abstract: Carbon dioxide (CO2) reduction to multi-carbon compounds at the cathode using chemolithoautotrophs is an emerging application of microbial electrosynthesis (MES). In this study, CO2 reduction in MES was investigated at hydrogen evolving potentials, separately by a mixed culture and Clostridium ljungdahlii, using a graphite felt and stainless steel assembly as cathode. The mixed culture reactor produced acetate at the maximum rate of 1.3 mM d(-1), along with methane and hydrogen at -1.1 V/Ag/AgCl. Over 160 days of run-time in four fed-batches, 26% of bicarbonate was converted to acetate between day 28 and 41, whereas in the late batches, methane production prevailed. Out of 45 days of run-time in the C. ljungdahlii reactor, 2.4 mM d(-1) acetate production was achieved at -0.9 V/Ag/AgCl in Batch 1. Simultaneous product degradation occurred when the mixed culture was not selectively enriched. Hydrogen evolution is potentially the rapid way of transferring electrons to the biocatalysts for higher bioproduction rates.
authors.affiliation: Separation & Conversion Technologies, Flemish Institute for Technological Research (VITO), Mol, Belgium; Sub-department of Environmental Technology, Wageningen University, Wageningen, The Netherlands.
authors.forename: Suman
authors.initials: S
authors.lastname: Bajracharya
authors.affiliation: Sub-department of Environmental Technology, Wageningen University, Wageningen, The Netherlands.
authors.forename: Annemiek
authors.initials: A
authors.lastname: ter Heijne
authors.affiliation: Separation & Conversion Technologies, Flemish Institute for Technological Research (VITO), Mol, Belgium.
authors.forename: Xochitl
authors.initials: X
authors.lastname: Dominguez Benetton
authors.affiliation: Separation & Conversion Technologies, Flemish Institute for Technological Research (VITO), Mol, Belgium.
authors.forename: Karolien
authors.initials: K
authors.lastname: Vanbroekhoven
authors.affiliation: Sub-department of Environmental Technology, Wageningen University, Wageningen, The Netherlands.
authors.forename: Cees J N
authors.initials: CJ
authors.lastname: Buisman
authors.affiliation: Sub-department of Environmental Technology, Wageningen University, Wageningen, The Netherlands.
authors.forename: David P B T B
authors.initials: DP
authors.lastname: Strik
authors.affiliation: Separation & Conversion Technologies, Flemish Institute for Technological Research (VITO), Mol, Belgium. Electronic address: deepak.pant@vito.be.
authors.forename: Deepak
authors.initials: D
authors.lastname: Pant
mesh_terms: D000085:Acetates / Q000378:metabolism; D052818:Autotrophic Processes; D001639:Bicarbonates / Q000378:metabolism; D001674:Bioelectric Energy Sources; D018441:Biofilms / Q000254:growth & development; D019149:Bioreactors; D002245:Carbon Dioxide / Q000378:metabolism*; D002384:Catalysis; D018929:Cell Culture Techniques / Q000379:methods*; D003013:Clostridium / Q000378:metabolism; D055664:Electrochemical Techniques; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D006859:Hydrogen / Q000378:metabolism; D010084:Oxidation-Reduction; D013193:Stainless Steel / Q000737:chemistry*
chemical_list: D000085:Acetates; D001639:Bicarbonates; D013193:Stainless Steel; D002245:Carbon Dioxide; D006108:Graphite; D006859:Hydrogen
keywords: Biocathode; Bioproduction; CO(2) reduction; Hydrogen evolution; Microbial electrosynthesis