Effect of Fe/HA modified anode on MFC power generation and nitrogen removal performance

Abstract

Iron humic acid complex (Fe/HA) was selected as the anode material for its good redox activity,and the effect of Fe/HA modified anode on the power generation and nitrate degradation performance of MFC was investigated.Fe/HA modified anode was prepared by electrodeposition method.The surface morphology and active functional groups of the prepared anode were measured by scanning electron microscopy and flourier transform infrared spectroscopy;cyclic voltammetry curve,tafel curve,and electrochemical impedance spectroscopy curve were used to investigate the electrochemical performance of Fe/HA modified anode;and the performance of MFC was investigated with the synthetic nitrate wastewater.Results showed that Fe/HA modified anode has a loose cluster structure and redox-active functional groups;compared with the control anode,the charge transfer amount,exchange current density and charge transfer impedance of the Fe/HA modified anode improved by 75.82%,14.95% and 17.60%;compared with the control anode MFC,the maximum average output voltage and denitrification efficiency of Fe/HA modified anode MFC were increased by 16.52% and 6.47%.The Fe/HA modified anode has effectively increased the number of redox-active functional groups and the area of microbial attachment on the anode surface,thereby improving the electron transfer efficiency and further achieving the enhancement of the MFC power generation and nitrogen removal efficiency.This work provides theoretical basis for the development of metal humic acid complex anodes and their applications in MFC wastewater treatment field.

Keywords

• bio-eneygy; fe/ha; microbial fuel cells; electrochemical properties; electricity production; denitrification