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With the development of industry, water resources have been seriously polluted, posing a great threat to human health and ecological development, and it is urgent to realize the efficient treatment of sewage-containing wastewater. The CoSx modified by thioacetamide grew in the interlayer of graphene oxide, which provided the composite membrane with self-cleaning ability, and at the same time enlarged the interlayer channels, which resulted in the flux and hydrophilicity significantly better than that of GO, and the retention rate of different types of oil-in-water emulsions was above 99 %. Encouragingly, the GO@CoSx-activated PMS system exhibited extremely high degradation performance for methylene blue. After 5 cycles, the flux of the composite membrane to the oil red-petroleum ether-oil-in-water emulsion under the light condition was higher than that under the dark condition, and the retention rate was kept at 99.93 %, with excellent antifouling performance. The composite membrane showed good degradation of methylene blue under alkaline conditions (99.84 %) and excellent removal of oil red-petroleum ether-oil-in-water emulsion under strong acid/alkaline conditions (99.37 %). The composite membrane has good chemical stability and mechanical properties for long-term use. This study will provide a new idea for the separation of oil-water emulsions, which has a broad application prospect. [Display omitted] • CoSx insertion into GO nanospheres. • The CoSx@GO composite improves the wettability and photo-degradation efficiency. • The CoSx@GO composite membranes have self-cleaning ability and stable oil-water separation. • Under the irradiation of visible light, organic pollutants can be degraded by the prepared composite membranes. [ABSTRACT FROM AUTHOR]

In this project, the Titanium dioxide nanowire (TiO 2 Nw) and layered double hydroxide (LDH) were introduced into the reduced graphene oxide (RGO) to make a composite material and then were assembled on the cellulose acetate (CA) membrane into photocatalytic composite membrane (RLT) through vacuum filtration with photocatalytic effect. The photocatalytic composite membrane (RLT) with high permeability and high rejection was constructed. Compared with other ratios of RLT membranes, RLT-0.5 composite membrane had a higher water flux of 432.38 L·m−2h−1bar−1, and the rejection rate of dye were above 99%. In the rejection process of 10 cycles, that the rejection rate and flux of RLT-0.5 composite membrane to methylene blue (MB), malachite green (Mg) and Congo red (CR) were more stable regardless of whether there was light or no light. Of course, the rejection effect was better under light conditions, showing its excellent photocatalytic performance. In conclusion, RLT-0.5 composite membrane had excellent water purification ability and photocatalytic efficiency, which made it have a wide application in water treatment. • Co-intercalation of TiO 2 and LDH to RGO photocatalytic composite membranes were prepared and characterized. • RLT-0.5 composite membrane had good hydrophilicity and dye removal effect. • RLT-0.5 composite membrane had photocatalytic self-cleaning ability and stable separation ability. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) is a typical type of anionic clay minerals. In this study, an SDS-LDH with sodium dodecyl sulfate (SDS) intercalation was prepared by the ion exchange method, and the modified SDS-LDH was successfully combined with graphene oxide (GO). In the presence of dopamine, partial reduction of GO to reduced graphene oxide (RGO). RGO/PDA/SDS-LDH (RPS) composite material was prepared successfully and used in the field of membrane separation. The RPS-2 composite membrane combines the advantages of GO and SDS-LDH, which can increase GO flux while maintaining a high rejection rate. The flux was increased from 10.21 L·m−2h−1bar−1 of GO to 79.24 L·m−2h−1bar−1 of RPS-2, and the rejection rate of various dyes was above 97%. The rejection rate of methylene blue (MB) 97.34% was maintained after 10 cycles, and its flux loss rate is only 45.32%. The composite membrane had good stability under different pH conditions, which provides a basis for the practical application of the membrane. [Display omitted] • The ion exchange method was used to successfully insert SDS into LDH and increase the interlayer spacing of LDH. • RPS-2 composite material was prepared by cross-linking with dopamine. • RPS-2 composite membrane can keep stable and filter the dye 10 times. [ABSTRACT FROM AUTHOR]

Nowadays, oily wastewater is a severe threat to the living environment of humankind. In recent years, MOF materials have shown great application potential in membrane separation and treatment of oily wastewater. In this paper, the mixed cellulose ester membrane (MCEM) was modified by polydopamine, and the NH 2 -MIL-125 (Ti)/Sep(sepiolite)/PDA composite membrane was prepared by simple vacuum filtration. The composite membrane had super-hydrophilic performance and underwater super-oleophobic performance, and could effectively separate oil-water emulsion separation performance. Also, the composite membrane showed good repeatability. After 10 cycles, the retention rate of petroleum ether-in-water emulsion was still more than 99%, and the flux was more than 2000 L· m − 2 · h − 1 . Since strong adhesion ability of PDA and the covalent interaction between NH 2 -MIL-125(Ti) and Sep, the chemically stable NH 2 -MIL-125(Ti)/Sep/PDA composite membrane was exposed to the strong acid (pH=1), alkali (pH=11), and salt (5% saturated NaCl) solutions showed excellent chemically stable. These outstanding properties made the composite membrane have great potential in the removal of oily wastewater. [Display omitted] • The composite membrane has good chemical stability in pH = 1, pH = 11%, and 5%NaCl. • After 10 cycles, the separation rate of the oil/water emulsions was above 99%. • The composite membrane had a high-efficiency separation performance of oil-in-water emulsion. [ABSTRACT FROM AUTHOR]