초록
<P><B>Summary</B></P><P>We report the first single‐chamber microbial electrochemical cell for conversion of CO<SUB>2</SUB> to CH<SUB>4</SUB>, with an average CH<SUB>4</SUB> production rate of 0.47 ± 0.05 mL day<SUP>−1</SUP> cm<SUP>−2</SUP> at an applied potential of 600 mV, utilizing a methanogenic microbial community collected from the formation water in the San Juan coal basin (Colorado, USA). CH<SUB>4</SUB> production was only observed at the graphite rod cathode after an electrochemical pre‐treatment that facilitates biofilm formation. The carbon contained within the CH<SUB>4</SUB> arose predominantly from the CO<SUB>2</SUB> source, as verified by experiments during which the CO<SUB>2</SUB> source was repeatedly turned off and on. Modest quantities of acetic acid and ethanol were also produced. DNA extraction and sequencing from the microbial community showed that from the Archaea kingdom, only 2 species survived prolonged exposure to CO<SUB>2</SUB> and CH<SUB>4</SUB> production, <I>methanobacterium sp</I>. (81.4%), and <I>methanoculleus sp.</I> (18.6%), while in the bacterial kingdom, <I>anaerobaculum thermoterrnum</I> (67.1%) was the predominant surviving species.</P>