title: Effect of the anode feeding composition on the performance of a continuous-flow methane-producing microbial electrolysis cell.
abstract: A methane-producing microbial electrolysis cell (MEC) was continuously fed at the anode with a synthetic solution of soluble organic compounds simulating the composition of the soluble fraction of a municipal wastewater. The MEC performance was assessed at different anode potentials in terms of chemical oxygen demand (COD) removal efficiency, methane production, and energy efficiency. As a main result, about 72-80% of the removed substrate was converted into current at the anode, and about 84-86% of the current was converted into methane at the cathode. Moreover, even though both COD removed and methane production slightly decreased as the applied anode potential decreased, the energy efficiency (i.e., the energy recovered as methane with respect to the energy input into the system) increased from 54 to 63%. Denaturing gradient gel electrophoresis (DGGE) analyses revealed a high diversity in the anodic bacterial community with the presence of both fermentative (Proteiniphilum acetatigenes and Petrimonas sulphurifila) and aerobic (Rhodococcus qingshengii) microorganisms, whereas only two microorganisms (Methanobrevibacter arboriphilus and Methanosarcina mazei), both assignable to methanogens, were observed in the cathodic community.
authors.affiliation: Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185, Rome, Italy, marco.zeppilli@uniroma1.it.
authors.forename: Marco
authors.initials: M
authors.lastname: Zeppilli
authors.forename: Marianna
authors.initials: M
authors.lastname: Villano
authors.forename: Federico
authors.initials: F
authors.lastname: Aulenta
authors.forename: Silvia
authors.initials: S
authors.lastname: Lampis
authors.forename: Giovanni
authors.initials: G
authors.lastname: Vallini
authors.forename: Mauro
authors.initials: M
authors.lastname: Majone
mesh_terms: D001419:Bacteria / Q000737:chemistry* / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism*; D044822:Biodiversity; D001674:Bioelectric Energy Sources / Q000382:microbiology*; D057919:Biological Oxygen Demand Analysis; D004560:Electricity; D004566:Electrodes / Q000382:microbiology*; D004572:Electrolysis; D008697:Methane / Q000378:metabolism*; D062065:Wastewater / Q000737:chemistry / Q000382:microbiology
chemical_list: D008697:Methane; D062065:Wastewater