Different refractory organic substances degradation and microbial community shift in the single-chamber bio-photoelectrochemical system. (July 2020) - Qin, Shanming
Graphical abstract: Highlights: A bio-photoelectrochemical system was developed with BiOBr photocathode. Degradation performances of AO7, 2, 4-DCP and CAP in the BPES were compared. Lower photocathode potentials under radiation conduced to pollutants mineralization. Microbial community in the BPES anodic biofilms shifted with various wastewaters. Geobacter and Pseudomonas were dominated microbial species in the illuminated BPES. Abstract: The single-chamber bio-photoelectrochemical system (BPES) with a BiOBr photocathode was developed for acid orange 7 (AO7), 2, 4 dichlorophenol (2, 4-DCP) and chloramphenicol (CAP) degradation under solar irradiation. Photoelectrochemical characterizations showed that the optimized BiOBr-photocathode exhibited great light-response property and excellent electrochemcial performance. Moreover, desired TOC removals were achieved for various organic pollutants, with the values of 90.97% (AO7), 81.41% (2, 4-DCP) and 78.47% (CAP). Besides, the lower cathode potentials in the illuminated BPESs were favorable to efficient pollutants degradation. Significant microbial community shifts were observed among the inoculation and anodic biofilms from the BPES, and the most dominated species in anodic biofilms acclimated to various pollutants were Geobacter and Pseudomonas, which have the abilities of extracellular electrons transfer and organics degradation. Some other species that different from the inoculation were also identified from the BPES biofilms. This study suggested that BPES had great potential for refractory organics degradation.