同步脱氮除硫燃料电池的电化学特性研究

同步脱氮除硫工艺以硝态氮作为电子受体，硫化物作为电子供体，通过以废治废，去除氮硫污染物。本文构建了双室型微生物燃料电池（microbial fuel cell，MFC），将同步脱氮除硫工艺与MFC相结合，在处理废水的同时生产电能。与化学对照组相比，该同步脱氮除硫MFC具有高基质去除性能和产电性能。当进水硝态氮和硫化物的浓度分别为95.54和540 mg·L^-1，反应时间为20 h时，硝态氮和硫化物的去除率分别高达96.50%和99.64%；最大电流密度达457.20 mA·m^-2，稳定电流密度为30.33 mA·m^-2。通过循环伏安法、极化曲线法和电化学阻抗分析，探究了同步脱氮除硫MFC的电化学特性。结果表明，在同步脱氮除硫MFC电极上，同步发生了脱氮除硫反应，该MFC最大功率密度为75.70 mW·m^-3，内阻约为2 474 Ω，其对同步脱氮除硫MFC电化学性能具有制约作用。

Electrochemical characteristics of microbial fuel cells treating nitrate and sulfide simultaneously

In the process of simultaneous nitrate and sulfide removal, nitrate is used as electron acceptor along with sulfide as electron donor, which can realize controlling waste by waste, and remove pollutants containing nitrogen and sulfur at the same time. This paper presents an approach to construct dual-chamber microbial fuel cell (MFC), combining the process of simultaneous nitrate and sulfide removal, hance attaining wastewater treatment and power generation concurrently. Compared with the chemical control experiment, the MFC treating sulfide and nitrate simultaneously displays good performance of substrate removal and electricity production. When the influent concentration of nitrate and sulfide are 95.54 and 540 mg·L^-1, the removal percentages of nitrate and sulfide reach 96.50% and 99.64%, respectively, with the reaction time of 20 h. The maximum current density is as high as 457.20 mA·m^-2, while the stable current density is 30.33 mA^-1·m^-2. The electrochemical characteristics of the MFC are also evaluated by polarization curve, cyclic voltammetry and electrochemical impedance analysis. The results show that there is a simultaneous sulfide and nitrate removal reaction occurred on the electrode of the MFC. The maximum power density of the MFC is up to 75.70 mW·m^-3, and its internal resistance is about 2 474 Ω, the diffusion internal resistance is the electrochemical performance-limiting factor of the MFC.