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• Coagulation/co-catalytic membrane system integrated coagulation, filtration and AOP. • Fe3+ served as both the coagulant for DOM removal and PMS activator. • MoS 2 in catalytic membrane accelerate the redox cycling of Fe species. • Surface-bound radicals enable efficient BPA removal and in-situ membrane cleaning. • The system showed stable performance during 53 h treatment of WWTP effluent. Low-pressure catalytic membranes allow efficient rejection of particulates and simultaneously removing organics pollutant in water, but the accumulation of dissolved organic matters (DOM) on membrane surface, which cover the catalytic sites and cause membrane fouling, challenges their stable operation in practical wastewater treatment. Here we propose a ferric salt-based coagulation/co-catalytic membrane integrated system that can effectively mitigate the detrimental effects of DOM. Ferric salt (Fe3+) serving both as a DOM coagulant to lower the membrane fouling and as a co-catalyst with the membrane-embedded MoS 2 nanosheets to drive perxymonosulfate (PMS) activation and pollutant degradation. The membrane functionalized with 2H-phased MoS 2 nanosheets showed improved hydrophilicity and fouling resistance relative to the blank polysulfone membrane. Attributed to the DOM coagulation and co-catalytic generation of surface-bound radicals for decontamination at membrane surface, the catalytic membrane/PMS/ Fe3+ system showed much less membrane fouling and 2.6 times higher pollutant degradation rate in wastewater treatment than the catalytic membrane alone. Our work imply a great potential of coagulation/co-catalytic membrane integrated system for water purification application. [Display omitted] [ABSTRACT FROM AUTHOR]

• The introduced PAC optimizes the assembly of heterogeneous FeS x on S-ZVI/PAC. • PAC physically adsorbs isolated FeS x allowed chemically assembled FeS x on S-ZVI. • The chemical assembly of FeS x is superior to physical adsorption on S-ZVI. • PAC adsorbs FeS x to obtain electron properties matching its adsorption threshold. Specifically designing the heterogeneous interface in sulfidated zero-valent iron (S-ZVI) has been an effective, yet usually overlooked method to improve the decontamination ability. However, the mechanism behind FeS x assembly remains elusive and the lack of modulating strategies that can essentially tune the applicability of S-ZVI further imposes difficulties in creating better-performing S-ZVI with heterogeneous interface. In this study, by introducing powdered activated carbon (PAC) during S-ZVI preparation, S-ZVI/PAC microparticles were prepared to modulate the assembly pattern of FeS x for the applicability and reactivity of the material. S-ZVI/PAC showed robust performance in Cr(VI) sequestration, with 11.16 and 1.78 fold increase in Cr(VI) reactivity compared to ZVI and S-ZVI, respectively. This was attributed to the fact that the introduced PAC could acquire FeS x to enhance the electron transfer capacity matching its adsorption threshold, thus helping to accommodate the transfer of the reduction center to PAC in S-ZVI/PAC. In optimizing the FeS x allocation between ZVI and PAC, the chemical assembly of FeS x on S-ZVI was superior to physical adsorption. Critically, we found that isolated FeS x in the prepared solution was physically adsorbed by the PAC, allowing chemically assembled FeS x on the S-ZVI. This was achieved by controlling the addition sequence of Na 2 S and PAC, as it effectively controlled the release rate and content of Fe(II) in the preparation solution. S-ZVI/PAC was demonstrated to be extremely effective in simulated wastewater and electrokinetics-permeable reactive barrier (EK-PRB) treatments. Introducing PAC enriches the diversity of sulfidation mechanisms and may realize the universality of the S-ZVI/PAC application scenarios. This study provides a new interface optimization strategy for S-ZVI targeted design towards environmental applications. [Display omitted] [ABSTRACT FROM AUTHOR]