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Graphical abstract Highlights • The new multifunctional UF membrane with ultrahigh MOF loading of 67% was prepared. • The new membrane showed much better efficiency for MB removal comparatively. • Acceptable ultrafiltration and permeability performance of the new membrane was kept. • The relationship and contribution of adsorption & catalytic oxidation were clarified. • The mechanism of decontamination, ultrafiltration and permeability was proposed. Abstract Multifunctional ultrafiltration membranes need to be further developed with ultrafiltration performance and high multifunctional decontamination efficiency. Here, the MIL-PVDF multifunctional ultrafiltration membrane with ultrahigh MIL loading was demonstrated by a new blending method of predispersion in acetone and thermally induced phase separation. Due to the improved dispersity and restriction of pore size, the MIL-53(Fe) mass loading was as high as approximately 61%. The new membrane showed high performance for methylene blue (MB) removal and maintained high permeability and ultrafiltration efficiency. The characteristics of the membranes were analyzed to explain the above advantages. Meanwhile, compared to the traditional blend ultrafiltration membrane, the 67-MIL-PVDF membrane showed an 9-fold increase in effective treatment volume for more than 75% MB removal. The contribution and efficiency of adsorption and catalytic oxidation were analyzed and explained. The relationship between them was confirmed as being independent, and the reasons for this independence were proposed. Additionally, the mechanism of multifunctional decontamination and permeability by MIL-PVDF membranes was proposed. Moreover, the 67-MIL-PVDF membrane was also suitable for long-term run and real wastewaters treatment. In conclusion, this study sheds new light on the preparation strategy for multifunctional blend ultrafiltration membranes with ultrahigh particles loading displaying high decontamination and permeability performance. [ABSTRACT FROM AUTHOR]

Annular iron sheet (AIS), playing a dual role of anode electrode and source of activator, was combined with electrolysis technology for the activation of persulfate to improve the degradation of 2, 4-dinitrophenol (DNP) in aqueous solution. In this study, effects of current density (0–10.0 mA/cm 2 ), persulfate (PS) dosage (0–8.0 mM), initial pH (3.0–11.0), reaction temperature (25–60 °C) and reaction time (0–30 min) on COD removal of DNP in aqueous solution were investigated, respectively. COD removal reached its maximal value (63.4%) after 15 min treatment due to the synergistic effect in electro/AIS/PS system under the optimal conditions. Furthermore, comparative studies of 7 different experimental processes were setup. In addition, the reasonable DNP degradation pathway was proposed based on intermediates detected by HPLC. According to characterization analysis of SEM-EDS, XRD and XPS of the generated flocculation in electro/AIS/PS system, the possible reaction mechanism was proposed in detail. In a word, the electrolysis process coupled with annular iron sheet as anode activating persulfate technology shows a significant synergetic effect in enhancing degradation of DNP in aqueous solution. [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]