RT journal article T1 Biogas upgrading with hydrogenotrophic methanogenic biofilms. A1 Maegaard, Karen A1 García Robledo, Emilio Guillermo A1 Kofoed, M. V. W. A1 Agneessens, L. M. A1 de Jonge, N. A1 Nielsen, J.L. A1 Ottosen, L. D. M. A1 Nielsen, L.P. A1 Revsbech, Niels Peter A2 Biología K1 Microsensor K1 Biofilm K1 CO limitation K1 Methane K1 Methanogenesis K1 Mass transfer AB Hydrogen produced from periodic excess of electrical energy may be added to biogas reactors where it is converted to CH4 that can be utilized in the existing energy grid. The major challenge with this technology is gas-to-liquid mass transfer limitation. The microbial conversions in reactors designed for hydrogenotrophic methanogenesis were studied with microsensors for H2, pH, and CO2. The H2 consumption potential was dependent on the CO2 concentration, but could partially recover after CO2 depletion. Reactors with 3-dimensional biofilm carrier material and a large gas headspace allowed for a methanogenic biofilm in direct contact with the gas phase. A high density of Methanoculleus sp. in the biofilm mediated a high rate of CH4 production, and it was calculated that a reactor filled with 75% carrier material could mediate a biogas upgrading from 50 to 95% CH4 within 24 h when an equivalent amount of H2 was added. PB Elsevier SN 0960-8524 YR 2019 FD 2019-09 LK http://hdl.handle.net/10498/35233 UL http://hdl.handle.net/10498/35233 LA eng DS Repositorio Institucional de la Universidad de Cádiz RD 13-nov-2026