Source of methane and methods to control its formation in single chamber microbial electrolysis cells

摘要：

Methane production occurs during hydrogen gas generation in microbial electrolysis cells (MECs),particularly when singlc-chamber systems are used which do not keep gases generated at the cathode separate from the anode.Few studies have examined the factors contributing to methane gas generation or the main pathway in MECs.It is shown here that methane generation is primarily associated with current generation and hydrogenotrophic methanogenesis and not substrate (acetate).Most methane was produced at the end of a batch cycle when hydrogen and carbon dioxide gases were present at the greatest concentrations.High applied voltages reduced methane production.Little methane (＜4%) accumulated in the gas phase at an applied voltages of 0.6 to 0.9 V over a typical 24 h cycle.However,when the applied voltage was decreased to 0.4 V,there was a greater production of methane than hydrogen gas due to low current densities and long cycle times. These results demonstrate that methane production in single chamber ME Cs is primarily associated with hydrogen gas production,and not acetoclastic methanogenesis.Methane generation will therefore be difficult to control in mixed culture MECs that produce high concentrations of hydrogen gas.By keeping cycle times short,and using higher applied voltages (≥0.6 V),is possible to reduce methane gas concentrations (＜4%) but not eliminate methanogenesis in MECs.

关键词： hydrogen microbial electrolysis cell (MEC) methane single chamber ezoelectrogenic

作者: Aijie Wang Wenzong Liu Shaoan Cheng Defeng Xing Bruce E.Logan

作者单位: State Key Lab of Urban Water Resource and Environment (SKLUWRE,HIT),Harbin 150090,P.R.China Department of Civil and Environmental Engineering,The Pennsylvania State University,Pennsylvania 168

会议类型: 国际会议

会议名称: 第二届中国微生物燃料电池研讨会(The 2nd Symposium on Microbial Fuel Cell in China)

会议地点: 北京

会议语种:英文

页码: 122-125

在线出版日期: 2009-11-13（万方平台首次上网日期，不代表论文的发表时间）