Co‐Substrate and Phosphate Buffer Enhanced Atrazine Degradation and Electricity Generation in a Bioelectrochemical System

Abstract

Refractory organic pollutant removal can be enhanced by a bioelectrochemical system via the addition of electron donors/acceptors. In this study, a single‐chamber soil microbial fuel cell (MFC) was constructed, and electricity production and atrazine removal efficiency were assessed using different co‐substrates and phosphate buffer concentrations. The co‐substrates compensated for the lack of soil organic matter and provided a sufficient carbon source for microorganisms to facilitate MFC electricity generation and efficient atrazine removal. The maximum voltage (94 mV), power density (39.41 mW m−2), removal efficiency (85.30%), and degradation rate (1.68 mg kg−1 d−1) were highest in the soil MFCs with sodium acetate when compared with the other groups. Phosphate buffer significantly alleviated the dramatic soil pH change. The electricity generation and atrazine removal efficiency increased with the buffer concentration (0–0.10 g L−1). The maximum voltage (144 mV) and power density (89.35 mW m−2) were highest, total internal resistance (652 Ω) was lowest, and atrazine removal efficiency (90.95%) and degradation rate (1.54 mg kg−1 d−1) were determined in the soil MFCs with the phosphate buffer concentration of 0.10 g L−1, and. These results indicate that the co‐substrate and phosphate buffer can enhance the electricity generation of soil MFCs and atrazine removal.