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In this study, cobalt molybdate (CoMoO 4) activated peracetic acid (PAA) was developed for water purification. CoMoO 4 /PAA system could remove 95% SMX with pseudo-first-order reaction rate constant of 0.15410 min−1, which was much higher than CoFe 2 O 4 /PAA, FeMoO 4 /PAA, and CoMoO 4 /persulfate systems. CoMoO 4 /PAA system follows a non-radical species pathway dominated by the high-valent cobalt (Co(IV)), and CH 3 C(O)OO• shows a minor contribution to decontamination. Density functional theory (DFT) calculation indicates that the generation of Co(IV) is thermodynamically more favorable than CH 3 C(O)OO• generation. The abundant Co(IV) generation was attributed to the special structure of CoMoO 4 and effect of molybdenum on redox cycle of Co(II)/Co(III). DFT calculation showed that the atoms of SMX with higher ƒ0 and ƒ- values are the main attack sites, which are in accordance with the results of degradation byproducts. CoMoO 4 /PAA system can effectively reduce biological toxicity after the reaction. Benefiting from the selective of Co(IV) and CH 3 C(O)OO•, the established CoMoO 4 /PAA system exhibits excellent anti-interference capacity and satisfactory decontamination performance under actual water conditions. Furthermore, the system was capable of good potential practical application for efficient removal of various organics and favorable reuse. Overall, this study provides a new strategy by CoMoO 4 activated PAA for decontamination with high efficiency, high selectivity and favorable anti-interference. [Display omitted] • Synergic effect of Co and Mo in cobalt molybdate enhances PAA activation. • High-valent cobalt was identified as the main active species for decontamination. • Special structure and Mo for Co redox cycle cause abundant Co(IV) generation. • Degradation pathways were proposed and biological toxicity was reduced. • Excellent anti-interference and various pollutant removal efficiency were exhibited. [ABSTRACT FROM AUTHOR]

• A dual-layer membrane was used for performance enhancement of Fenton-like oxidation. • Sequential decontamination was achieved by a UF layer above a catalysis layer. • BPS and macromolecular substances removal were enhanced in multicomponent wastewater. • The enhancement mechanisms by sequential interception-oxidation were proposed. Fenton-like oxidation for multicomponent wastewater treatment suffers from a low efficiency due to non-selective nature of produced reactive species. In this study, a multifunctional dual-layer ultrafiltration membrane (Seq-ICM) was synthesized for multiple pollutants decontamination. Characterizations of the membranes indicate that Seq-ICM comprises a skin layer for ultrafiltration, and a porous support layer loaded with ∼50% MIL-53(Fe) for catalysis. With bovine serum albumin coexisting, Seq-ICM can remove 75.7% bisphenol S (BPS), which is much higher than that of a simultaneous interception-catalysis membrane (44.2 %). For multicomponent wastewater treatment, Seq-ICM system can save ∼59%-67% oxidant dosage as well compared with catalysis alone membrane system to achieve 50% BPS removal. Furthermore, the decontamination mechanisms were investigated to explain the advantages of Seq-ICM. Sequential interception and oxidation process by Seq-ICM leads to the interception of macromolecular substances first, following by catalytic oxidation of low-molecular-weight organics. This process prevents macromolecular substances from competing for active species with low-molecular-weight organics, thereby enhancing selectivity and oxidation efficiency. Meanwhile, Seq-ICM shows satisfactory BPS removal efficiency for treatment of 2865 L/m2 synthetic solution, as well as in real wastewater matrix. We believe the proposed technology based on a composite membrane is promising for the removal of multicomponent substances from wastewater. [ABSTRACT FROM AUTHOR]