Zero-valent iron to advance anaerobic membrane bioreactors for wastewater treatment and reuse: A critical review

Abstract

Anaerobic membrane bioreactors (AnMBRs) have been widely applied for wastewater treatment and resource recovery, but face several technical challenges, such as unstable methane (CH4) production, limited contaminant removal, and membrane fouling. Zero-valent iron (ZVI) can be a potential additive to improve AnMBRs performance by regulating anaerobic reaction conditions, electron transfer modes and microbial community structure. Thus, this review critically evaluated the role of ZVI to advance AnMBRs performance for wastewater treatment and resource recovery. Key physicochemical characteristics of ZVI were analyzed to highlight its potential for AnMBRs enhancement. The performance of ZVI and its modification to assist AnMBRs, regarding CH4 production, contaminant removal and membrane fouling, were discussed. Furthermore, future perspectives to the development of ZVI-assisted AnMBRs toward industrial application for practical wastewater treatment and resource recovery were provided.