Enhanced degradation performance and microbial community diversity analysis of a microbial electrolytic cell with a double chamber for the treatment of wastewater containing p-bromoaniline

Abstract

The feasibility and superiority of bioelectrochemical systems for the degradation of p-bromoaniline (p-BrA) have been confirmed previously. In this research, the influences of the cathode potential and initial p-BrA concentration on the performance of microbial electrolytic cells (MECs) were investigated. The degradation performance and degradation kinetics of a MEC and a conventional anaerobic reactor (CAR) were compared to analyze degradation products. The microbial species diversity in the MECs was studied to analyze changes following the introduction of electric potential. The optimized solution had a cathode potential of 0.5 V, an initial concentration of 50 mg/L, and a pH value of 7. Under these conditions, the removal efficiency for p-BrA was 94.94 %. In addition, after transitioning from a CAR to an MEC, the bacterial species diversity of the biocathode took place significant changes. Several types of aniline-degrading bacteria, such as Proteobacteria and Patescibacteria, and methane-producing bacteria, such as Anaerolineaceae, were dominant in the community of the cathodic biofilm. Experimental results showed that the removal of p-BrA degradation products was closely related to the diversity of cathode bacteria.