Abstract:Steroid estrogens (SEs) are a kind of emerging and harmful pollutants that have garnered worldwide attention. Traditional wastewater treating methods generally fail to eliminate them entirely. Humic acid (HA), as an electron transport mediator, can significantly improve the electron transport efficiency of extracellular respiration during microbial metabolism. In view of the special electrochemical properties of HA, its application to microbial fuel cell (MFC) systems is expected to achieve efficient degradation of SEs with low energy consumption. In this study, the MFC anode was modified with a metal compound (HA@Fe3O4) formed by HA and strong capacitive nano-Fe3O4 particles. 17α-ethynylestradiol (EE2) was selected as the representative SEs to evaluate the degradation performance of the modified MFC anode. The results showed that the presence of HA not only increased electron transfer efficiency between microorganisms and the anode, but also enhanced the electric production performance by improving the anode"s capacitance. The maximum power density in the MFC system increased to 522.32 mW/m2 after the combination of HA. Also, the anode modified with HA@Fe3O4 could significantly improve the degradation efficiency of EE2 by MFC. Additionally, EE2 at low concentrations promoted the performance of MFC, but inhibited the activity of microorganisms and reduced the electricity generation efficiency of MFC at high concentrations. This study provided a certain research basis for the effective application of MFC in actual wastewater.