微生物燃料电池处理含柠檬酸钠废水的研究

Study of wastewater containing sodium citrate degraded by microbial fuel cell

柠檬酸钠由于其优良的性质被广泛应用于食品、医药、化工等诸多领域,越来越广泛的应用导致工业和市政污水中柠檬酸钠的含量升高,加剧了水体的富营养化。将柠檬酸钠作为微生物燃料电池(microbialfuelcell,MFC)阳极底物,研究得到了柠檬酸钠单独作为混合菌种MFC底物时的产电性能。结果显示,与乙酸钠和葡萄糖相比,以柠檬酸钠为底物的MFC(Na3C6H5O7-MFC)获得的最大功率密度为742.96mW·m^-2,是乙酸钠(NaAc-MFC)和葡萄糖(Glu-MFC)的1.77倍和1.12倍。NaAc-MFC和Glu-MFC的启动时间分别约为Na3C6H5O7-MFC(57h)的1.8倍和2.9倍。同时,Na3C6H5O7-MFC对COD的去除率为87.65%,与NaAc-MFC和Glu-MFC相差不大。Na3C6H5O7-MFC的库仑效率高达61.31%,明显优于NaAc-MFC和Glu-MFC。实验结果表明MFC可以有效地降解柠檬酸钠,能够处理含柠檬酸钠废水,并为柠檬酸钠单独作为底物应用于MFC提供了依据。

Sodium citrate (Na3C6H5O7) is widely used for food, medicine, chemical industry and many other fields due to its excellent performance. The extensive application has resulted in an increase of sodium citrate in industrial and municipal sewage and it aggravates the eutrophication of the water body. In this study, sodium citrate is applied as substrate for the anode electricigens and with which microbial fuel cell (MFC) represents good electricity generation performance. The results show that Na3C6H5O7-MFC achieves a maximum power density of 742.96 mW·m^-2, which is 1.77 and 1.12 times of that of sodium acetate (NaAc-MFC) and glucose (Glu-MFC), respectively. The start-up time of NaAc-MFC and Glu-MFC are about 1.8 and 2.9 times of that of Na3C6H5O7-MFC (57 h). The Coulombic efficiency of Na3C6H5O7-MFC is 61.31%, which is obviously superior to NaAc-MFC and Glu-MFC. This indicates that MFC can degrade sodium citrate in wastewater effectively, which provides a possibility of sodium citrate alone as substrate for MFC research.