title: Simultaneous sulfide removal, nitrification, and electricity generation in a microbial fuel cell equipped with an oxic cathode.
abstract: With sulfide as an anodic electron donor and ammonium as a cathodic substrate, the feasibility of simultaneous sulfide removal, nitrification, and electricity generation was investigated in a microbial fuel cell (MFC) equipped with an oxic cathode. Successful simultaneous sulfide removal, nitrification, and electricity generation in this MFC were achieved in 35 days, with the sulfide and ammonium removal percent of 92.7 ± 1.4 and 96.4 ± 0.3%, respectively. The maximum power density increased, but the internal resistance decreased with the increase of feeding sulfide concentration from 62.9 ± 0.3 to 238.5 ± 0.2 mg S/L. Stable ammonium removal with complete nitrification, preparing for future denitrification, was obtained throughout the current study. Sulfide removal loading significantly increased with the increase of feeding sulfide concentration at each external resistance, but no significant correlation between sulfide removal loading and external resistance was found at each feeding sulfide concentration. The charge recovery and anodic coulombic efficiency (CE) significantly decreased with the increase of external resistance. High feeding sulfide concentration led to low anodic CE. Granular sulfur deposition was found on the anode graphite fiber. The appropriate feeding sulfide concentration for sulfide removal and sulfur deposition was deemed to be 178.0 ± 1.7 mg S/L, achieving a sulfur deposition percent of 69.7 ± 0.6%.
authors.affiliation: School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan, 430070, China.
authors.forename: Renbing
authors.initials: R
authors.lastname: Bao
authors.affiliation: School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan, 430070, China. shzhang@whut.edu.cn.
authors.forename: Shaohui
authors.identifier: http://orcid.org/0000-0002-8081-9635
authors.initials: S
authors.lastname: Zhang
authors.affiliation: School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan, 430070, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhao
authors.affiliation: School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan, 430070, China.
authors.forename: Liuxiang
authors.initials: L
authors.lastname: Zhong
mesh_terms: D064751:Ammonium Compounds; D001674:Bioelectric Energy Sources; D058440:Denitrification; D004560:Electricity; D004566:Electrodes; D058465:Nitrification; D013440:Sulfides
chemical_list: D064751:Ammonium Compounds; D013440:Sulfides
keywords: Electricity generation; External resistance; Microbial fuel cell; Nitrification; Sulfide removal; Sulfur deposition