title: Bio-Electrocatalytic Application of Microorganisms for Carbon Dioxide Reduction to Methane.
abstract: We present a study on a microbial electrolysis cell with methanogenic microorganisms adapted to reduce CO2to CH4with the direct injection of electrons and without the artificial addition of H2or an additional carbon source except gaseous CO2. This is a new approach in comparison to previous work in which both bicarbonate and gaseous CO2served as the carbon source. The methanogens used are known to perform well in anaerobic reactors and metabolize H2and CO2to CH4and water. This study shows the biofilm formation of those microorganisms on a carbon felt electrode and the long-term performance for CO2reduction to CH4using direct electrochemical reduction. CO2reduction is performed simply by electron uptake with gaseous CO2as the sole carbon source in a defined medium. This "electrometabolism" in such microbial electrolysis cells depends strongly on the potential applied as well as on the environmental conditions. We investigated the performance using different adaption mechanisms and a constant potential of -700 mV vs. Ag/AgCl for CH4generation at 30-35 °C. The experiments were performed by using two-compartment electrochemical cells. Production rates with Faradaic efficiencies of around 22 % were observed.
authors: Linz Institute for Organic Solar Cells, Johannes Kepler University Linz, Altenbergerstraße 69, 4040, Linz, Austria.
authors: Stefanie
authors: http://orcid.org/0000-0003-4948-0837
authors: S
authors: Schlager
authors: acib GmbH, Linz, Austria.
authors: Marianne
authors: M
authors: Haberbauer
authors: PROFACTOR GmbH, Steyr, Austria.
authors: Anita
authors: A
authors: Fuchsbauer
authors: acib GmbH, Linz, Austria.
authors: Christine
authors: C
authors: Hemmelmair
authors: Linz Institute for Organic Solar Cells, Johannes Kepler University Linz, Altenbergerstraße 69, 4040, Linz, Austria.
authors: Liviu Mihai
authors: LM
authors: Dumitru
authors: Linz Institute for Organic Solar Cells, Johannes Kepler University Linz, Altenbergerstraße 69, 4040, Linz, Austria.
authors: Gabriele
authors: G
authors: Hinterberger
authors: Linz Institute for Organic Solar Cells, Johannes Kepler University Linz, Altenbergerstraße 69, 4040, Linz, Austria.
authors: Helmut
authors: H
authors: Neugebauer
authors: Linz Institute for Organic Solar Cells, Johannes Kepler University Linz, Altenbergerstraße 69, 4040, Linz, Austria.
authors: Niyazi Serdar
authors: NS
authors: Sariciftci
mesh_terms: D001674:Bioelectric Energy Sources / Q000382:microbiology*; D018441:Biofilms; D002245:Carbon Dioxide / Q000378:metabolism*; D002384:Catalysis; D004563:Electrochemistry; D004579:Electron Transport; D008697:Methane / Q000378:metabolism*
chemical_list: D002245:Carbon Dioxide; D008697:Methane
keywords: biosynthesis; electrochemistry; enzyme catalysis; fuel cells; reduction