Research progress on using biological cathodes in microbial fuel cells for the treatment of wastewater containing heavy metals

Frontiers in Microbiology

Microbiology

Yu Li¹  Jianghang Ma¹  Bo Liu¹  Pengxiang Zhai¹  Xizi Long²  Zhiqiang Xu³  Hui Wang³ 

[1] Department of Municipal and Environmental Engineering, School of Water Resources and Hydro-Electric Engineering, Xi'an University of Technology, Xi'an, China;Key Laboratory of Typical Environmental Pollution and Health Hazards of Hunan Province, School of Public Health, Hengyang Medical School, University of South China, Hengyang, China;State Key Laboratory of Eco-Hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, China;Department of Municipal and Environmental Engineering, School of Water Resources and Hydro-Electric Engineering, Xi'an University of Technology, Xi'an, China;

关键词: microbial fuel cell;    biocathode;    heavy metal wastewater;    cathodic reduction;    electron transfer;   

DOI  :  10.3389/fmicb.2023.1270431

 received in 2023-07-31, accepted in 2023-09-04,  发布年份 2023

来源: Frontiers

【 摘 要 】

Various types of electroactive microorganisms can be enriched to form biocathodes that reduce charge-transfer resistance, thereby accelerating electron transfer to heavy metal ions with high redox potentials in microbial fuel cells. Microorganisms acting as biocatalysts on a biocathode can reduce the energy required for heavy metal reduction, thereby enabling the biocathode to achieve a lower reduction onset potential. Thus, when such heavy metals replace oxygen as the electron acceptor, the valence state and morphology of the heavy metals change under the reduction effect of the biocathode, realizing the high-efficiency treatment of heavy metal wastewater. This study reviews the mechanisms, primary influencing factors (e.g., electrode material, initial concentration of heavy metals, pH, and electrode potential), and characteristics of the microbial community of biocathodes and discusses the electron distribution and competition between microbial electrodes and heavy metals (electron acceptors) in biocathodes. Biocathodes reduce the electrochemical overpotential in heavy metal reduction, permitting more electrons to be used. Our study will advance the scientific understanding of the electron transport mechanism of biocathodes and provide theoretical support for the use of biocathodes to purify heavy metal wastewater.

【 授权许可】

Unknown   
Copyright © 2023 Wang, Zhai, Long, Ma, Li, Liu and Xu.