The coupling of persulfate activation and membrane separation for the effective pollutant degradation and membrane fouling alleviation

The membrane fouling is a thorny issue in membrane separation technology, which can significantly weaken its separation efficiency for wastewater. The coupling of membrane separation technology and advanced oxidation processes (AOPs) to construct a multifunctional catalysis-membrane system will be a promising solution to solve membrane fouling. This is because AOPs can remove pollutant, thereby alleviating membrane fouling and improving membrane flux. As a new generation of AOPs, persulfate (PS)-activation AOPs have attracted numerous attentions because of its strong oxidation. The coupling of PS-activation AOPs and membrane separation displays broad prospects in the wastewater treatment, and it has been widely studied in recent years. This review introduces PS-activation catalysis-membrane system (PACMS) for the wastewater treatment, including homogeneous and heterogeneous system. The activation method for PS in PACMS, including heat, ultraviolet, transition metal ion, transition metal compound, carbon material, photocatalysis, are discussed. Meanwhile, the mechanisms of PS activation, pollutant degradation, and fouling alleviation in PACMS are analyzed in detail. In addition, various preparation strategies of catalytic membrane such as blending method, in-situ growth method, and vacuum-assisted filtration method are summarized. Besides, the applications of PACMS for various wastewater treatments are highlighted. Finally, the future research directions and challenges of PACMS are prospected. This review will provide an in-depth understanding of PACMS to promote its further development in future practical applications.