title: Electricity generation and microbial community analysis of alcohol powered microbial fuel cells.
abstract: Two different microbial fuel cell (MFC) configurations were investigated for electricity production from ethanol and methanol: a two-chambered, aqueous-cathode MFC; and a single-chamber direct-air cathode MFC. Electricity was generated in the two-chamber system at a maximum power density typical of this system (40+/-2 mW/m2) and a Coulombic efficiency (CE) ranging from 42% to 61% using ethanol. When bacteria were transferred into a single-chamber MFC known to produce higher power densities with different substrates, the maximum power density increased to 488+/-12 mW/m2 (CE = 10%) with ethanol. The voltage generated exhibited saturation kinetics as a function of ethanol concentration in the two-chambered MFC, with a half-saturation constant (Ks) of 4.86 mM. Methanol was also examined as a possible substrate, but it did not result in appreciable electricity generation. Analysis of the anode biofilm and suspension from a two-chamber MFC with ethanol using 16S rDNA-based techniques indicated that bacteria with sequences similar to Proteobacterium Core-1 (33.3% of clone library sequences), Azoarcus sp. (17.4%), and Desulfuromonas sp. M76 (15.9%) were significant members of the anode chamber community. These results indicate that ethanol can be used for sustained electricity generation at room temperature using bacteria on the anode in a MFC.
authors.affiliation: Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: Jung Rae
authors.initials: JR
authors.lastname: Kim
authors.forename: Sok Hee
authors.initials: SH
authors.lastname: Jung
authors.forename: John M
authors.initials: JM
authors.lastname: Regan
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Logan
mesh_terms: D011211:Electric Power Supplies; D004560:Electricity; D000431:Ethanol / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D000431:Ethanol