title: Improved hydrogen production in the microbial electrolysis cell by inhibiting methanogenesis using ultraviolet irradiation.
abstract: Methanogenesis inhibition is essential for the improvement of hydrogen (H2) yield and energy recovery in the microbial electrolysis cell (MEC). In this study, ultraviolet (UV) irradiation was proposed as an efficient method for methanogenesis control in a single chamber MEC. With 30 cycles of operation with UV irradiation in the MEC, high H2 concentrations (>91%) were maintained, while without UV irradiation, CH4 concentrations increased significantly and reached up to 94%. In the MEC, H2 yields ranged from 2.87 ± 0.03 to 3.70 ± 0.11 mol H2/mol acetate with UV irradiation and from 3.78 ± 0.12 to 0.03 ± 0.004 mol H2/mol acetate without UV irradiation. Average energy efficiencies from the UV-irradiated MEC were 1.5 times of those without UV irradiation. Energy production from the MEC without UV irradiation was a negative energy yield process because of large amount of CH4 produced over time, which was mainly attributable to cathodic hydrogenotrophic methanogenesis. Our results clearly showed that UV irradiation could effectively inhibit methanogenesis and improve MEC performance to produce H2.
authors.affiliation: Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University , Guangzhou 510275, China.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Hou
authors.forename: Haiping
authors.initials: H
authors.lastname: Luo
authors.forename: Guangli
authors.initials: G
authors.lastname: Liu
authors.forename: Renduo
authors.initials: R
authors.lastname: Zhang
authors.forename: Jiayi
authors.initials: J
authors.lastname: Li
authors.forename: Shiyu
authors.initials: S
authors.lastname: Fu
mesh_terms: D000085:Acetates / Q000378:metabolism; D001419:Bacteria / Q000254:growth & development / Q000528:radiation effects; D001674:Bioelectric Energy Sources; D056804:Biofuels / Q000382:microbiology; D018533:Biomass; D002245:Carbon Dioxide / Q000378:metabolism; D015169:Colony Count, Microbial; D004560:Electricity; D004566:Electrodes; D004572:Electrolysis; D006859:Hydrogen / Q000378:metabolism*; D008697:Methane / Q000096:biosynthesis*; D014466:Ultraviolet Rays
chemical_list: D000085:Acetates; D056804:Biofuels; D002245:Carbon Dioxide; D006859:Hydrogen; D008697:Methane