混合菌群生物燃料电池的产电机理与特性

Mechanism and Characteristics of Electricity Generation in Microbial Fuel Cells Catalyzed by Mixed Culture

利用厌氧污泥为接种源构建双室微生物燃料电池(Microbial fuel cell,MFC),研究其电子传递机制,并考察其底物利用谱及阴极电子受体对产电性能的影响.结果表明:该MFC主要通过生物膜机制实现电子从有机物到固体电极的传递过程.该混合菌MFC的底物利用谱范围广泛,单糖、二糖、小分子有机酸等有机物均可作为电子供体产电,其中以蔗糖和乳糖为底物产电效果较好,最大功率密度分别为69.69 mW/m2和60.75 mW/m2;而以乙醇为底物时,COD负荷最高,达123.55 mg L-1d-1.阴极不同电子受体对混合菌群MFC的产电性能也有显著影响,其中以KMnO4为电子受体电池性能最好,最大功率密度达1 396.74 mW/m2.

Dual-chamber microbial fuel cells（MFCs） were constructed by inoculating anaerobic sludge.The extracellular electron transfer mechanism of mixed bacteria in MFC anode chamber,the utilization of substrates and cathodic electron acceptors were investigated.The results showed that the mixed bacteria formed thick biofilm on carbon felt anode to facilitate the electron transfer between organic matter and MFC anode.Additionally,the MFC was capable of using a wide variety of organic compounds as electron donors for power generation,including monosaccharide,disaccharide as well as several types of small molecular organic fatty acid and ethanol.While sucrose and lactose as electron donors,the maximum power densities of the MFCs reached 69.69 mW/m2and 60.75 mW/m2,respectively.The highest COD loading of 123.55 mg L-1d-1was attained with ethanol as electron donor.Acidic permanganate as the cathodic electron acceptor could greatly increase power production with the maximum power density of 1 396.74 mW/m2.