A nano zero-valent iron (NZVI) was added into sediments to enhance the capacities of sediment microbial fuel cells (SMFCs) for pollutant removal and electricity generation. Open and closed circuits were applied to confirm the impact of NZVI on the pollutant removal performance of SMFCs. The operation of SMFCs in a closed circuit with 0.06% NZVI produced a current density of 340.8 mA/m2. Adding 0.6% NZVI to closed-circuit SMFCs reduced hydrogen sulfide from 12.5 mg/L to 0 mg/L. Moreover, adding NZVI to closed-circuit SMFCs reduced phosphate concentration from 49 mg/L to 11 mg/L. With the same amount of NZVI, the pollutant removal in a closed circuit was higher than that in an open circuit because of the electricity flow at SMFCs. In conclusion, addition of NZVI to SMFCs effectively enhanced the produced current density and reduced the concentrations of hydrogen sulfide and phosphate in sediments.
- Current density