何丹,张尔翼,杨祖洁,余林鹏,周顺桂.甲烷生物燃料电池的产电影响因素及机制研究[J].环境科学学报,2021,41(9):3446-3456
甲烷生物燃料电池的产电影响因素及机制研究
- Research on the influencing factors and mechanisms of electricity generation of methane-driven microbial fuel cell
- 基金项目:国家自然科学基金(No.42077284,41701270);福建省自然科学基金(No.2019J01394);福建农林大学杰出青年科研人才计划项目(No.xjq201906)
- 何丹
- 福建农林大学资源与环境学院, 福州 350002
- 张尔翼
- 福建农林大学资源与环境学院, 福州 350002
- 杨祖洁
- 福建农林大学资源与环境学院, 福州 350002
- 余林鹏
- 福建农林大学资源与环境学院, 福州 350002
- 周顺桂
- 福建农林大学资源与环境学院, 福州 350002
- 摘要:考察了阳极电极材料、电极面积、电极电位、pH、阴极电子受体对甲烷生物燃料电池(MFC)产电性能的影响,并通过高通量测序、循环伏安法(CV)分析了其可能的电催化机制.结果表明,透气布/碳布(GTC)复合材料为阳极时产电性能(1251.3 mA·m-2)最佳,分别是石墨烯/中空纤维膜(G-HFM)阳极(34.8 mA·m-2)和碳布(CC)阳极(3.21 mA·m-2)的36倍和390倍;阳极面积越大,MFC启动时间越快,电流密度越大;当电极恒电位为0.1 V (vs.SHE)时,其产电能力较-0.1、+0.3及+0.5 V时高;pH=7最有利于产电;溶解氧为MFC阴极电子受体时,最大功2率密度(703.9 mW·m-2)优于铁氰化钾(457.2 mW·m-2)、空气阴极(124.2 mW·m-2)和高锰酸钾(20.7 mW·m-2)作为电子受体的MFC.阳极室微生物群落结构分析显示,电活性细菌Geobacter(17.14%)和Desulfovibrio(8.51%)为优势种,其产电机理可能是甲烷氧化菌(Methanobacterium、Methylomicrobium等)与电活性细菌协同氧化甲烷驱动MFC产电.添加NO气体、N-乙酰蛋氨酸和蛋白酶K均可明显抑制阳极生物膜的电化学活性,表明其胞外电子传递过程依赖细胞色素c、Ni-Fe氢酶及与电极接触的外膜蛋白的介导作用.
- Abstract:The effects of anode material, electrode area, electrode potential, pH and cathode electron acceptor on the electricity generation of methane-driven microbial fuel cell (MFC) were investigated in this paper, and cyclic voltammetry (CV) and high-throughput sequencing were performed to reveal the possible electrocatalytic mechanisms. The results showed that the gas diffusion cloth/carbon cloth (GTC) composite anode showed the best performance (1251.3 mA·m-2), which was 36 times and 390 times higher than that of graphene/hollow fiber membrane (G-HFM) anode (34.8 mA·m-2) and carbon cloth (CC) anode (3.21 mA·m-2), respectively. The larger the anode area, the higher the current density generated and the faster the reactor started up. When the electrode potential was poised at 0.1 V (vs. SHE), the power generation was the highest than those with potentials poised at -0.1 V, +0.3 V and +0.5 V. The most favorable pH for power generation was 7. When dissolved oxygen was served as the electron acceptor, the maximum power density (703.9 mW·m-2) was much higher than those with potassium ferricyanide (457.2 mW·m-2), air cathode (124.2 mW·m-2) and potassium permanganate (20.7 mW·m-2) as electron acceptors. The microbial community structure in anode chamber was dominated by Geobacter (17.14%) and Desulfovibrio (8.51%). Thus, the mechanism of electricity generation in MFC was speculated to be the synergistic cooperation between methanotrophs (Methanobacium, Methylomicrobium) and electroactive bacteria. The addition of NO gas, N-acetylmethionine and proteinase K could significantly inhibit the electrochemical activity of the anodic biofilm, indicating that the extracellular electron transfer process was mainly mediated by cytochrome c, Ni-Fe hydrogenase and outer membrane proteins contacted with anode.