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[Display omitted] • MOF-based liquid crystal dye/water separation membranes were fabricated. • Liquid crystal played an important role in the well-ordered membrane structure. • The separation membranes presented high water flux and excellent dye rejection. • The membranes exhibited excellent long-term stability, reusability and flexibility. High-performance membranes for effective dye/water separation are urgently desired in chemical industrial manufacture, and Metal-organic frameworks (MOFs) with abundant microporous structures are considered suitable candidates for fabricating separation membranes. However, for MOF-based membranes, maintaining superior separation efficiency while ensuring high water flux remains a challenge. In this study, a series of novel MOF-based composite materials (TFNs) and membranes oriented by electric fields (fio-TFNs) were fabricated using NH 2 -MIL-53(Fe), a thermotropic liquid crystal, poly (styrene-4-sulfonic acid), and polytetrafluoroethylene. The fio-TFN membranes exhibited characteristics of orientation and uniform distribution, and showed higher water flux and dye rejection compared with ordinary TFN membranes. This highlights the significant role played by the ordered orientation of liquid crystal molecules induced by the electric field in effective dye/water separation. High porosity is the basis of dye absorption, and the electrostatic interaction among structural charges and dyes is the dominant driving forces in these dye/water separation systems. The prepared fio-TFN membranes exhibited excellent performance in effective dye separation. For instance, the fio-TFN-1 membrane demonstrated high water flux (up to 255.9 L·m−2 h−1 bar−1) and excellent dye rejection rates (≥97 %, 92 %, and 82 % for methyl blue, congo red, and rhodamine B, respectively). Moreover, these prepared membranes exhibited excellent long-term stability, reusability, and flexibility, indicating their potential as high-performance separation membranes for wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • COF-SO 3 H/polydopamine was used as composite interlayer to tailor TFC-PC X membrane. • The interlayer served as a regulator to control the polyamide layer morphologies. • The hydrophilicity and surface charge of membrane were enhanced by the interlayer. • The TFC-PC 0.08 membrane exhibited high permeability and Na 2 SO 4 rejection. Thin-film composite nanofiltration (TFC NF) membranes can separate neutral/charged solutes and play an essential role in water purification. However, the permeability of traditional NF membranes is severely limited by excessive mass transfer resistance due to the thick polyamide (PA) layer. Introducing porous nanomaterials as an interlayer into PA NF membranes has been recognized as an effective approach to improve permeability. Herein, a novel composite interlayer consisting of anionic covalent organic frameworks with abundant sulfonic acid groups (COF-SO 3 H) and polydopamine was designed to regulate interfacial polymerization to construct the highly permeable TFC NF membranes. The surface negative charge and hydrophilicity of the TFC NF membranes can be controlled by the abundant polar groups in the composite interlayer. Moreover, mass transfer resistance can be reduced by introducing COF-SO 3 H to create additional water transport channels. The results showed that the optimal membrane manifested attractive permeability (44.2 L⋅m−2⋅h−1⋅bar−1) and a high Na 2 SO 4 rejection (98.7 %), almost 3-fold higher than that of the original TFC membrane. Furthermore, the optimal membrane exhibited favorable anti-fouling performance and stability. This work provides insight into strategies for fabricating highly permeable TFC NF membranes through the introduction of an interlayer. [ABSTRACT FROM AUTHOR]

• Asymmetric PEGylated PES membrane, with a thin dense layer atop and a microporous support layer beneath, successfully synthesized via simple thermal cross-linking and NIPs. • Excellent hemocompatibility displayed by PEGylated PES membrane in terms of protein adsorption, hemolysis, platelet adhesion and blood clotting. • Long-lasting surface stability, structure stability against wetting as well as cytocompatibility exhibited by PEGylated PES membrane. Excellent hemocompatibility and long-term stability against blood wetting are important properties required for artificial lung membrane, the core component in extracorporeal membrane oxygenator which is life-saving for patients with severe lung dysfunctions. Herein, novel hydrophilic modified polyethersulfone (PES) asymmetric membranes were synthesized via thermal cross-linking, and characterization via SEM, FTIR, 1H NMR and surface water contact angle measurements demonstrated that the modified asymmetric membranes composing a dense layer with hydrophilic surface on top of a microporous support layer were successfully fabricated without any observed defects. Among all the modified membranes, PEGylated PES membrane exhibited the smoothest membrane surface, improved mechanical property, good gas permeability and the best performance in hemocompatibility in terms of blood coagulation, protein adsorption and platelet adhesion. Moreover, the PEGylated PES membrane showed excellent long-term stability in membrane surface wettability as well as long-term stable performance against blood fouling and wetting. This research work provides valuable insights and new idea into synthesizing membranes, with simple synthesis process, long lasting high hemocompatibility and stability against wetting, for application as artificial lung membranes. [ABSTRACT FROM AUTHOR]

• PA/PEI-TA@MOF-808 thin film composite (TFC) membrane was fabricated. • TA@MOF-808 in support layer could regulate interfacial polymerization. • The TFC membrane achieved a retention rate of over 96.7% for rare earth ions. • Evaluated the acid resistance and operational stability of the TFC membrane. • The TFC membrane exhibited excellent selectivity for trivalent cations. Retrieval of rare earth ions from dilute wastewater produced from in-situ leach mining is a crucial approach to effectively mitigate the shortage of rare earth resources, and the employment of the membrane technology for recuperation of ionic rare earths is an energy-efficient and eco-friendly solution. In this study to optimize the use of the membrane technology for ionic rare earths recovery, TA@MOF-808 was fabricated by combining tannic acid (TA) with MOF-808 and then incorporated as nanoparticles into a polyetherimide (PEI) base membrane. On this basis, PA/PEI-TA@MOF-808 thin-film composite membranes were prepared via interfacial polymerization. TA@MOF-808 with its hydroxyl and carboxyl functional groups generated hydrogen and covalent bonds with the secondary amine groups of piperazine (PIP), which stored PIP and regulated its diffusion rate into the organic phase. Thereby, the membrane surface charge was modulated under acidic conditions, and a separation layer was reconstituted, improving the structural and operational stability of the membranes. The PA/PEI-TA@MOF-808 membrane exhibited a water flux of 42.1 L·m−2·h−1, and La3+, Y3+, and Gd3+ retention rates of 97.7 %, 96.7 % and 97.4 %, respectively. Separation tests, acid resistance tests, long-term operational stability tests and actual rare earth wastewater treatment tests revealed the PA/PEI-TA@MOF-808 membrane possessed outstanding ionic rare earth separation capability, consistent membrane flux, notable acid resistance, and operational stability, suggesting a bright future in the application for ionic rare earth recovery. [ABSTRACT FROM AUTHOR]

• 7,7′-OH-BINOL and diacyl chloride were used to prepare TFC OSN membranes. • The formed polyarylate layer show thin and high microporosity characters. • Two oil phase cross-linker result in nanofilms with diverse microstructures. • The optimal membrane shows methanol flux of 5.81 LMH/bar and MWCO of 288 Da. In recent years, OSN technology has gained great attention for its environmental friendly nature, energy efficiency, and small carbon footprint. Herein, we prepared TFC OSN membranes BINOL-TPC and BINOL-IPC with higher selectivity by employing a contorted molecule 7,7′-dihydroxy-2,2′-binaphthol (7,7′-OH-BINOL) with four functional groups and diacyl chloride (TPC/IPC) via interfacial polymerization (IP) method compared to with trimesoyl chloride (TMC). The use of monomer 7,7′-OH-BINOL with rigid, twisted and multiple reaction sites endow the resulted polyarylate layer with high microporosity and cross-linking density. Notably, the BINOL-TPC and BINOL-IPC membranes exhibited good performance in retaining small molecular solutes, with MWCO values of 288 and 344 Da, respectively. Meanwhile, the methanol permeance of the two composite membranes reach 5.81 and 7.06 LMH/bar, respectively. In addition, the membrane BINOL-TPC could achieve precise separation of mixed dyes with similar molecular weight but opposite charge. As can be seen, by designing and utilizing IP monomers with different structures and functionalities, it is possible to fabricate membranes with diverse microstructures and properties, ultimately leading to varied separation performances. This research offers some new insights in the view of molecular-level tailoring for the fabrication of high performance OSN membranes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The membranes were prepared by vacuum filtration COF with azobenzene functional groups. • The permeance of membranes increases from 19.56 to ∼ 42 L h−1 m−2 bar−1, dye rejection increases from 94.4 % to 99 %. • The surface charge, pore size and hydrophilicity of composite membranes could be regulated by light stimuli. • The membranes still maintained separation performance after high pressure (6 bar) and cyclic filtration. • The membranes exhibit good antifouling performance. Covalent organic framework (COF) holds great promise in affording precise and fast molecular separation. Inspired by the light-gated channels in cell membranes, we developed artificial light-gated molecular channel composite membranes by vacuum filtration COF with azobenzene (AZO) functional groups. The simple stimuli response could remotely adjust the membranes separation performance. The cis membranes with off state under ultraviolet (UV) light have higher dye rejection than trans membranes with on-state channels. The permeance of composite membranes increased from 19.56 to ∼ 42.30 L h−1 m−2 bar−1, dye (Rose Bengal (RB)) rejection increased from 94.40 % to 99.12 % after 10 min of 365 nm UV irradiation. In addition, the composite nanofiltration membranes exhibited good antifouling performance due to hydrophilic and highly smooth surface. By controlling the trans -to-cis AZO isomerization via UV /visible (Vis) light, the solvent permeance and dye rejection can be dynamically tuned due to the adjustable pore size. [ABSTRACT FROM AUTHOR]

• A Cu-Al bimetallic oxide @ PVDF composite membrane was designed and fabricated. • The composite membrane exhibited exceptional catalytic activity and stability. • PDS activation by the composite membrane followed an electron transfer mechanism. • Oxygen vacancy and electron-rich Cu sites facilitated the electron transfer process. • Electron transfer resulted in the selective oxidation of electron-rich organic compounds. The presence of environmental endocrine-disrupting compounds, such as bisphenol A (BPA), in aquatic environments poses a significant risk to both ecological integrity and human health. Although CuO has been reported as a catalyst for activating peroxydisulfate (PDS) to degrade BPA, it exhibits certain limitations, including low catalytic efficiency, aggregation, and challenges in terms of separation and reusability. In this study, we developed a composite poly (vinylidene fluoride) (PVDF)-based membrane incorporating Cu-Al bimetallic oxide (Cu-Al) to address these issues. Results revealed that when employing the 7 wt% Cu-Al @ PVDF composite membrane to activate 1 mM PDS, approximately 95.3 % of BPA was degraded within 60 min in static experiments. Furthermore, this composite membrane exhibited remarkable efficacy across a broad pH range (3–11) and demonstrated excellent resistance against diverse anionic species. The removal process is proposed to be dominated by electron transfer between the composite membrane, PDS, and BPA via a two-step mechanism: Firstly, electron-rich Cu sites and oxygen vacancies were formed in the composite membrane, facilitating PDS adsorption and electron transfer from Cu sites to PDS to form a ligand complex; subsequently, BPA was adsorbed by the membrane and acted as an electron donor to be oxidized by the ligand complex. As a result, this system showed remarkable selectivity for degrading electron-rich organic compounds with ionization potentials below 9.0 eV. Overall, this work successfully fabricated a catalytic membrane exhibiting efficient PDS activation capability along with selective oxidation performance and facile reusability, making it highly promising for wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] Improving the membrane durability without sacrificing perm-selectivity is an essential challenge in membrane technology. To address this challenge, a combination of incorporating bi-sulfonated covalent-organic frameworks nanosheets (TpPa-(SO 3 H) 2 CONs) and surface modification was used to modify thin-film composite (TFC) nanofiltration membranes. The nanofiltration experiments and molecular dynamics (MD) simulations revealed that nanosheets dispersed in n-hexane could significantly modulate the piperazine diffusion. At the optimal nanosheet addition amount of 0.004 g/100 ml n-hexane, the pure water permeance (PWP) and Na 2 SO 4 rejection of the thin-film nanocomposite (TFN) membranes increased to 9.35 L·m−2·h−1·bar−1 and 99.26 %. Meanwhile the corresponding values of the pristine TFC membranes were only 5.45 L·m−2·h−1·bar−1 and 96.99 %, respectively. Membrane surface modification was performed on the optimal TFN surface. When the surface was modified with Tp at a concentration of 0.004 g/100 ml n-hexane for 9 s, the PWP further increased to 11.42 L·m−2·h−1·bar−1, which was almost 2.10 folds higher than the original TFC membranes. In contrast, the Na 2 SO 4 rejection slightly increased to 99.36 %. Moreover, the static immersion experiments results indicated that the surface modification enhanced the membrane durability. This study proved that the association of these two methods provides a simple and effective strategy to design nanofiltration membranes with excellent separation performance and durability simultaneously. [ABSTRACT FROM AUTHOR]

[Display omitted] • A composite adsorptive membrane with PEI modification was fabricated. • It demonstrates strong adsorption capacity, kinetics, and selectivity for Cr(VI). • It can be effectively regenerated for sustainably utilized with an alkaline solution. • Longer-term filtration proved its applicability with satisfactory treatment volume. The development of an efficient and economical method to remove the toxic Cr(VI) from water is a global challenge. This study developed a new composite adsorptive membrane by combining polyacrylonitrile (PAN) as a substrate with crosslinked polyethyleneimine (PEI) to efficiently remove Cr(VI) from wastewater. After optimizing the preparation conditions of the material, the Cr(VI) removal by PEI/GMA@PAN was investigated using batch adsorption and longer-term filtration experiments. The composite adsorptive membrane exhibited a high adsorption capacity, reaching a maximum of 89.16 mg/g, along with fast adsorption kinetics that achieved equilibrium within 100 min for Cr(VI) removal. Even in the presence of coexisting ions, PEI/GMA@PAN membrane maintained a high efficiency in removing Cr(VI). The removal mechanism mainly relied on electrostatic interactions and the reduction of Cr(VI) to Cr(III). Notably, long-term filtration experiments substantiated the membrane's effectiveness in removing Cr(VI) from synthetic wastewater, with an impressive treatment volume of 342 L/m2. The optimized PEI/GMA@PAN membrane also demonstrated low PEI leaching across a wide pH range and the potential for re-utilization through four-round cycles, underscoring its promising applicability in wastewater treatment. Therefore, the newly synthesized composite membranes show potential for the removal of Cr(VI) from wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Coated PDMS on SSZ-13 layer to enhance separation performance. • Investigated PDMS concentration and coating time to optimize performance. • Enhanced CO 2 /CH 4 selectivity 20-fold, maintaining CO 2 permeance in single and mixed gas. • Achieved peak performance with ideal CO 2 /CH 4 selectivity of 428 and CO 2 permeance of 9.5 x 10-7 [mol/(m2sPa)] in single gas. • Obtained CO 2 /CH 4 selectivity of 290 and CO 2 permeance of 3.5 x 10-7 [mol/(m2sPa)] in mixed gas. This work aims to investigate and develop a concept for CO 2 separation based on PDMS/SSZ–13 (high-Si CHA) composite membranes. Firstly, an Al 2 O 3 support was coated with SSZ-13 zeolite layer, then to increase the performance of the membrane, a Polydimethylsiloxane layer was effectively deposited homogeneously to cover the cracks and defects of the zeolite layer. The results of single gas permeation measurements displayed a notable increase in ideal CO 2 /CH 4 selectivity up to 428 at the lowest PDMS concentration of 0.5 vol%. Moreover, a coating time of 10 min preserved CO 2 permeance while increasing CO 2 /CH 4 selectivity from 5 to 120. A twentyfold increase in CO 2 /CH 4 selectivity was noted with mixed gas permeation without a reduction in CO 2 permeance. Quantitative and qualitative microscopic analyses were also carried out on the coated membrane to better understand its morphology and microstructure. The outcomes indicated that PDMS layer decreased the permeation of N 2 and CH 4 and enhanced surface affinity toward CO 2 , resulting in reduced defects in the zeolite membranes and enhanced selectivity for CO 2 /N 2 and CO 2 /CH 4. [ABSTRACT FROM AUTHOR]

[Display omitted] • PES/SiO 2 membranes for desalination prepared via sol–gel method showed better performances than pure PES membrane. • Dense PES/SiO 2 composite membrane had a high permeate flux, salt rejection, and good mechanical properties. • In-situ SiO 2 provides both a reinforcement effect and an increased hydrophilicity of PES membrane. • High water purity was obtained by using P_60-S7 membrane. In this study, polyethersulfone (PES) membranes for desalination were prepared under different evaporation temperatures. The morphology of the PES membranes was evaluated using scanning electron microscopy, which revealed that at a low evaporation temperature (30 °C and 40 °C) the membranes had a porous structure (the pore size in the range of 11–20 μm), whilst at a high evaporation temperature (50 °C and 60 °C) they had a more dense structure. To improve the desalination efficiency of the PES membrane, silica was generated in-situ in the PES membrane via a sol–gel reaction. The advantage of this technique was to give a good silica dispersion under a mild synthesis condition for the silica compared to the conventional direct mixing method. The effect of the in-situ silica content generated in the PES membrane on its hydrophilicity, mechanical properties, permeate flux, and salt rejection was investigated. The PES membrane prepared under an evaporation temperature at 60 °C with 7 % by weight in-situ silica showed the highest permeate flux (19.55 kg/m2h) and salt rejection (98.9 %). Accordingly, this membrane can be applied to deliver high quality fresh water for daily life. [ABSTRACT FROM AUTHOR]

[Display omitted] • Composite pervaporation desalination membranes prepared via Catechol-amine chemistry. • Tannic acid (TA) crosslinked PEI (polyethyleneimine) was the selective layer material. • The composite membranes were prepared by a step-wise coating method. • The critical synthesis parameters of the TA-PEI composite membranes were discussed. • The TA-PEI pervaporation membrane has high flux and antifouling performance in desalination. Compared with reverse osmosis, pervaporation is less influenced by the osmosis pressure of the feed solution, which endows it as an attractive desalination technology. Many researches focus on developing high-performance pervaporation desalination membranes. Bio-inspired polyphenol coatings are versatile tools for engineering membrane surfaces. Here, catechol-amine chemistry was the first time applied to construct dense composite pervaporation desalination membranes via a stepwise coating method. Tannic acid (TA) and polyethyleneimine (PEI) were chosen as typical materials. Fabrication parameters, including TA and PEI concentrations in the coating solution, pH, and thermal annealing, are crucial to the desalination performance of the resulting membranes. The TA-PEI interactions were studied by the UV–Vis absorption spectroscopy method. The membrane prepared at optimal conditions exhibits excellent desalination performance. The water flux was 43 kg/(m2·h) at 50 °C for the feed of 3.5 wt% NaCl solution (95 kg/(m2·h) at 70 °C). The intrinsic hydrophilicity of the selective layer material ensures the membrane processes of good antifouling performance. This work demonstrates the possibility and potential of applying bio-inspired catechol-amine chemistry to prepare pervaporation desalination membranes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two novel amino-functionalized PILs were designed by incorporating the amino groups into PILs. • The copolymerized PILs were prepared as composite membranes to explore the effect of different chemical structures on their separation performance. • Highly CO 2 -selective membranes with a superior CO 2 /N 2 selectivity of 173.5 were obtained. • Membranes with both fixed-site and mobile carriers provide the synergistic effect for CO 2 -facilitated transport. Design and synthesis of novel poly(ionic liquids) (PILs) containing amino groups hold great promise in CO 2 separation fields owing to the tunability of the cation and anion, as well as the high CO 2 affinity of the amino groups. Herein, two novel amino-functionalized PILs were designed for the preparation of composite membranes by casting the synthesized PIL-based solutions on the top of polysulfone ultrafiltration membranes to explore the effect of different chemical structures on the separation performances of the NH 2 -carrier-based membranes. Highly CO 2 -selective membranes with a CO 2 /N 2 selectivity of 173.5 were obtained by introducing the mobile carrier of 2-(1-piperazinyl) ethylamine sarcosine (PZEA-Sar) into the amino-functionalized PIL-based membranes, which provides the synergistic effect from both fixed-site and mobile carriers for promoting CO 2 -facilitated transport. Thus, the developed membranes may offer a high energy-efficiency process for industrial CO 2 capture. [ABSTRACT FROM AUTHOR]

[Display omitted] • Membranes with a "brick and mortar" biomimetic structure were prepared by 2D α-Co(OH) 2 and SA. • The α-Co(OH) 2 /SA membranes were dense, hydrophilic, and negatively charged. • NF and antimicrobial properties of α-Co(OH) 2 /SA membrane were superior to those of SA membrane. • The α-Co(OH) 2 /SA(5/5) membrane exhibited high dye rejection, but low salt rejection. Combining novel two-dimensional (2D) and polymeric materials can construct high-performance membranes for nanofiltration (NF) applications. In this study, 2D α-Co(OH) 2 nanosheets and sodium alginate (SA) were assembled to fabricate a serial of α-Co(OH) 2 /SA NF membranes with a "brick and mortar" biomimetic structure for dye removal. The prepared α-Co(OH) 2 nanosheets were characterized with a typical 2D structure, and the α-Co(OH) 2 /SA membranes exhibited dense selective layers with hydrophilic negatively charged surfaces. Furthermore, the membrane thickness and NF performance both varied depending on the mass ratios of α-Co(OH) 2 to SA, giving the tunability of the membrane structure and NF performance of α-Co(OH) 2 /SA membranes. The prepared α-Co(OH) 2 /SA membranes exhibited superior separation performance compared to pure SA membranes, with the α-Co(OH) 2 /SA(5/5) membrane demonstrating exceptional dye rejection of 99.92% for Rose Bengal (RB) and long-term stability lasting 48 h. They were effective against both gram-positive and gram-negative bacteria. In addition, the α-Co(OH) 2 /SA(5/5) membrane exhibited low rejection towards salt solutions (6.05% for NaCl, 9.63% for Na 2 SO 4). The α-Co(OH) 2 /SA(5/5) membrane offers a promising application for separating dye/salt solutions, which provides potential in designing and fabricating novel composite membranes with 2D materials. [ABSTRACT FROM AUTHOR]

• MWCNT membrane was applied to separate H 2 O/D 2 O in membrane distillation process. • Structures of GO-MWCNT composite membranes affected H 2 O/D 2 O separation performance. • 3D hierarchical GO-MWCNT composite membrane gave high H 2 O/D 2 O separation performance. • The correlation of structure-separation performance for H 2 O/D 2 O was reviewed. Recently, membrane distillation (MD) processes using two-dimensional graphene oxide (GO) membranes exhibited good light water/deuteriated water (H 2 O/D 2 O) separation performance, which depended on membrane materials and structures. This raises the need for the development of novel membrane materials and revealing the relationship of membrane structure-separation performance to further increase separation performance. Here, one-dimensional (1D) MWCNT-based membrane was explored for the separation of H 2 O/D 2 O using the water source with specially chosen concentration of deuterium (D) in air–gap membrane distillation processes, and the resultant MWCNT membrane gave lower permeation flux and similar separation factor compared with the pristine GO membrane. Then GO-MWCNT composite membranes with different structures obtained by mixing various weight ratios of GO: MWCNTs were investigated, and their separation performance was found to be related with membrane structures. The resulted 3D hierarchical GO-MWCNT composite membrane (G/M−1:3) gave the highest permeation flux of 0.947 L·m−2·h−1 among all GO-MWCNT composite membranes, higher than that of the pristine GO membrane, while the separation factor of G/M−1:3 (1.045) and the pristine GO membrane (1.046) was comparable. Furthermore, the correlation of membrane structure-separation performance was reviewed. These results demonstrate the first example of MWCNT membrane and related composite membranes for H 2 O/D 2 O separation and suggest that H 2 O/D 2 O separation performance in membrane distillation processes can be improved by tailoring the structure of GO-MWCNT composite membranes. As the separation of H 2 O/D 2 O is usually used as a model in the laboratory for light water/tritiated water (H 2 O/HTO) separation process, this approach can guide for developing novel membrane materials and structures to deliver appropriate H 2 O/HTO separation processes needed in the nuclear energy field. [ABSTRACT FROM AUTHOR]

[Display omitted] • A defect-free and thin PA membrane was constructed on tubular ceramic support. • The prepared membrane features a unique skyloft-like structure. • The resultant membrane shows a high water permeance up to 736.6 L m-2h−1 MPa−1. • The prepared membrane demonstrates high dyes/antibiotics desalination selectivity (up to 197). • A long-term cross-flow nanofiltration and a high-pressure test indicate the outstanding stability. Polyamide (PA) thin-film composite membrane has been widely used in water/wastewater treatment, but construction of such membrane on a three-dimensional inorganic macroporous support remains a challenge, thus limiting the further application under harsh conditions. Herein, we propose a skyloft-like PA membrane on a commercial tubular ceramic macrofiltration support. This membrane built on stilts comprises an ultrathin PA canopy of ∼ 33 nm and pillars (∼1 μm-thick) of vertically aligned CoAl-layered double hydroxide (LDH) nanosheets and covalent organic framework (COF) nanospheres. The prepared PA/OH-COF/F-COF/LDH membrane shows a high water permeance of up to 736.6 L m-2h−1 MPa−1 together with a satisfactory rejection rate of > 90 % for various small molecules including dyes and antibiotics (> ∼1 nm). The resultant membrane also demonstrates a good dye desalination performance (with a selectivity of up to 197), illustrating an outstanding permselectivty. A long-term and continuous cross-flow nanofiltration indicates a robust stability of the membrane. [ABSTRACT FROM AUTHOR]

[Display omitted] • MoS 2 & PEI modified positively charged membrane was fabricated. • The membrane showed more than 98 % rejection for Cs(I), Sr(II), Hg(II), Pb(II), As(III). • Heavy metals were removed by electrostatic repulsion coupling adsorption. • The membrane exhibited significant reusability and anti-fouling performance. The simultaneously efficient removal of radionuclides and heavy metals is an important and challenging topic for aquatic environmental protection. In this work, molybdenum disulfide (MoS 2) with heavy metal ion adsorption capacity and positively charged polyethyleneimine (PEI) were used to fabricate a novel layer-by-layer (LbL) self-assembly composite membrane by a simple alternating immersion method. The unique structure with positive charge ensures high removal for toxic metals (R Cs(I) = 99.83 %, R Sr(II) = 100 %, R Hg(II) = 99.2 %, R Pb(II) = 98.13 %, R As(III) = 98.5 %). The inherent low resistance channels in MoS 2 provided the optimized composite membrane an elevated water flux. Long-term experiments and membrane regeneration also demonstrated that the membrane possesses exceptional stability and reusability in removing low levels of radionuclides Cs(I) and Sr(II) from water. This study confirms the feasibility of the MoS 2 -PEI composite membrane for the treatment of contaminated waters containing radionuclides and heavy metals. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of special spherical 3D-S-COF with high crystallinity by interfacial polymerization. • Preparation of high stability MXene/3D-S-COF membranes followed composite method. • MXene layer has super hydrophilic, photocatalytic and fouling resistant. • 3D-S-COF layer has good separation efficiency and emulsion flux of oil–water. Three-dimensional sphere covalent organic framework (3D-S-COF) membranes have received increasing attention in the field of oily wastewater and industrial organic matter due to their rich pore structure as well as having many exposed functional group sites. However, the synthesis of conventional imine COF through the Schiff base method, which suffers from the easy hydrolysis under organic solvent conditions. Herein, a novel super-wettable MXene/3D-S-COF composite membrane for oil–water emulsion separation was prepared by depositing MXene nanosheets on oxidized amide COF from the imine COF. The hydroxyl groups of the COF membrane not only improved the water permeability but also formed hydrogen bonds with the MXene layer, which enhanced the interaction and formed the high stability composite membrane. The porous 3D-S-COF and the zigzag MXene layer work synergistically to enable emulsion fluxes up to 240 L·m−2h−1 bar−1 and the separation efficiency is more than 98 %. In addition, the residual mass of the composite membrane remained above 95 % after 10 days of immersion in various solvents, and it also has photocatalytic properties and good resistance to fouling. This study provides a brand new idea for the use of MXene/3D-S-COF based composite membrane for oil–water emulsion separation. [ABSTRACT FROM AUTHOR]

• A green based biochar/iron/zinc nanocomposite filler via facile method. • Interfacial polymerisation was used to fabricate TFN membranes. • The green nanofiller membranes exhibited enhanced permeation and rejection. • Efficient permeation and removal of MO and salts. • TFN membrane exhibited superior stability and antifouling ability. The advancement in the development of nanofillers for thin-film nanocomposite (TFN) membranes, particularly those derived from eco-friendly sources, has gained increasing recognition. This is largely due to their potential to markedly improve both permeation and selectivity. However, the investigation of biochar (BC), a by-product of biomass pyrolysis, as a distinctive nanofiller remains limited. This study investigates the incorporation of porous iron/zinc (Fe/Zn) modified biochar (MBC) into a polyamide active layer for the purpose of fabricating TFN membranes on a polyethersulfone (PES) substrate via interfacial polymerisation (IP). Imaging confirmed the formation of metal nanoparticles dispersed uniformly throughout the porous BC substrate. Further crystallinity and surface analysis suggest strong interactions between metal and BC substrate, with a surface area of 117.99 m2/g and high nanofiller pore volume of 7.72 cm3/g. The effects of incorporating MBC into both the membrane substrate and polyamide (PA) layers on the physicochemical properties, permeation, and rejection of salts and dye were examined. Scanning Electron Microscopy (SEM) imaging has shown that the incorporation of MBC in both the substrate and PA layer results in the seamless formation of a finger-like structure spanning both layers. This incorporation also causes a minor increase in the surface roughness of the PA layer. Fourier transform Infra-Red (FT-IR) spectroscopy shows an enhancement in hydrophilic functional groups (–OH and –COOH) on the membrane surface, as evidenced by the reduced contact angle value of 55°. Permeation and rejection testing indicate that M5, where MBC was incorporated in both substrate and thin film structure, was the best performing membrane, with water permeance from the feeds of water, MO, MgSO 4 and NaCl solutions of 46.55 ± 0.08, 44.49 ± 0.28, 37.43 ± 0.36, and 21.55 ± 0.03 Lm2h-1bar−1, respectively. Rejection of MO, MgSO 4 and NaCl were recorded to be 99.53 ± 0.02, 99.25 ± 0.09 and 46.99 ± 0.69 %. This study provides a compelling perspective on the application of green-derived BC as a nanofiller in the fabrication of TFN membranes for desalination, resulting in enhanced water product quality. [ABSTRACT FROM AUTHOR]

• Mullite-based ceramic composite membranes were developed by combining in-situ growth of ZIF-8 and coating of ZIF-8-doped PDMS. • The mullite-based ceramic composite membranes exhibited good gas separation properties and thermal stability. • The M/ZIF-8/PDMS@ZIF-8 demonstrated a high CO 2 permeance of 3050 GPU and superior CO 2 /N 2 selectivity of 10.7. • The M/ZIF-8/PDMS@ZIF-8 exhibited excellent CO 2 separation stability at 80 °C. The development of high-performance composite membranes for efficient CO 2 /N 2 separation is essential for reducing CO 2 emissions. However, achieving a balance between permeance and selectivity remains a challenge. In this work, two CO 2 permeable mullite ceramic-based composite membranes were made using fly ashes and α-Al 2 O 3 as raw materials for mullite substrates, ZIF-8 nanofillers, and PDMS rubber polymer as gas separation materials. To enhance CO 2 permeance and CO 2 /N 2 selectivity, the M/PDMS@ZIF-8 composite membrane was prepared by dip-coating a ZIF-8 doped PDMS active layer (PDMS@ZIF-8) on the surface of the mullite-based substrate (M 0). Subsequently, the M/ZIF-8/PDMS@ZIF-8 composite membrane was fabricated by in-situ growing ZIF-8 and followed by coating a PDMS@ZIF-8 functional layer on the M 0 surface. The results indicated that the optimal M/PDMS@ZIF-8 membrane with 1 % of ZIF-8 exhibited an ultrahigh CO 2 permeance of 4756 GPU and a good CO 2 /N 2 selectivity of 10.07 at room temperature under 0.2 MPa. While the optimized composite membrane M/ZIF-8/PDMS@ZIF-8 with 0.8 wt% of ZIF-8 achieved a high CO 2 permeance of 3050 GPU and superior CO 2 /N 2 selectivity of 10.7. Furthermore, the latter displayed long-term permeation stability at 80 °C. The facile preparation process and cost-effective nature of the ceramic-based composite membrane demonstrate great potential for applications in CO 2 capture from flue gas. [ABSTRACT FROM AUTHOR]

• A novel Mg(OH) 2 /PVA/ZnO membrane with efficient oil–water separation was prepared by one-step electrodeposition. • The membrane durability, water flux, and separation efficiency were significantly enhanced. • The membrane can separate a wide range of oil–water mixtures and emulsions along with resistance to oil fouling. The release of oily wastewater is a significant threat to both the environment and the sustainable development of society. The challenge of oil–water separation, which includes immiscible oil/water mixtures and emulsions, is exacerbated by the substantial volume of oily wastewater generated in industrial processes and daily activities. In this study, a one-step electrodeposition method was employed to fabricate a composite membrane composed of Mg(OH) 2 /PVA/ZnO. A uniform electric field was applied between the cathode and anode to facilitate the deposition of PVA and ZnO nanoparticles onto various metallic mesh of the cathode in the presence of Mg2+. The generation of hydrogen at the mesh surface facilitated the development of a superhydrophilic/underwater superoleophobic composite structure featuring micropores and nanosheets. The membrane durability, water flux, and separation efficiency were significantly enhanced, achieving a separation efficiency of 99.8 % and a water flux of 3.2 × 105 L·m−2·h−1. The membrane demonstrated excellent performance in separating a wide range of oil–water mixtures and emulsions, along with outstanding chemical stability and resistance to oil fouling. [ABSTRACT FROM AUTHOR]

[Display omitted] • Large scale (lateral dimension: 8.3 μm) MXene monolayer were successfully prepared in this study. • A mass transfer channels with high permeance was constructed with the strategy of intercalation Al(OH) 3 into MXene layers. • The composite membranes fabricated in this study showed high permeance, rejection, and long-term operational stability. In this study, Ti 3 C 2 T x layers with an average lateral size of approximately 8.3 μm were prepared. The LLM composite membranes synthesized from these layers not only possessed long and narrow mass transfer channels but also further prevented the generation of internal non-selective defects. Additionally, a strategy of compositing these Ti 3 C 2 T x layers and Al(OH) 3 was adopted. The strategy contributed to expanding the interlayer distances of the composite membranes and adjusting the in-plane stacking order, thereby facilitating the construction of mass transfer channels characterized by high permeance within the membranes. This resulted in the preparation of LLMA membranes. Among these LLMA membranes, the LLMA-1:7 composite membranes displayed outstanding performance in the sieving process. Their permeances were more than 10 times higher than those of the LLM membranes (with a thickness of 1 μm). Also, the rejection ratio for CV dye could even exceed 99 %, and the operational stability was also significantly improved. These advantages enabled them to avoid some of the shortcomings commonly found in two-dimensional (2D) separation membranes to a certain extent. In summary, the LLMA-1:7 composite membranes designed in this study demonstrated superior overall performance, compared to the majority of the previously reported 2D membranes. This research is expected to establish a solid foundation for the application of 2D MXene membranes in the field of water treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • DAR was first used for fabricating a novel PA TFC membrane. • The morphology of this PA nanofilm was regulated by DAR content. • Water flux of the membrane was up to 212.5 LMH/bar while 100 % rejection for BBR. • Efficient fraction was achieved with 98 % CR rejection and >95 % salt passage. • The prepared membrane exhibited excellent antifouling and stability. Developing ultrathin polyamide thin-film composite (PA TFC) membrane with ultrahigh performance to overcome the perm-selectivity upper bound of molecular separation is still the major challenge for practical applications. Herein, we first designed an ultrahigh performance PA TFC membrane fabricated by interfacial polymerization of 4,6-diaminoresorcinol dihydrochloride (DAR) and trimethyl chloride (TMC) on the substrate. The structural morphology of the PA active layer and the separation performance of the resultant membrane were tuned by DAR dosage. This ultrathin PA TFC membrane breaks the trade-off between water permeance and dye (NOM) selectivity. Accordingly, the optimal membrane had a water flux of 212.5 LHM/bar with superior rejection of 98.6 % and 100 % for BBR and CR, respectively, surpassing the upper-bound limit of most reported polymeric membranes thus far. The membranes also exhibited a high salt passage (>95 %), achieving an impressive screening capacity for the dye/salt mixture as well as excellent antifouling and operation stability performance. This work sheds light on the regulation of the PA selective layer via new amine monomer featuring ultrahigh performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Temperature responsive copolymer was grafted onto a nano-Ag decorated ceramic substrate. • A six-fold enhancement of pure water flux from 20 °C to 85 °C. • Oil removal exceeding 98% and dye degradation surpassing 99% in oil-in-dye containing water treatment. • Self-cleaning property and anti-irreversible fouling ability of the membrane at 85 °C. Composite membrane that integrating catalytic degradation with membrane separation offers a promising solution for one-step treatment of complex wastewater. However, the challenge of membrane fouling by multi-component pollutants, impedes their broader applications. Herein, building on previous work, temperature responsive polymers are grafted onto a nano-Ag decorated ceramic substrate for enhanced dye removal and anti-fouling property. The grafting process is optimized in terms of reaction temperature (75 ℃), reaction time (4 h), and monomer concentration (VMDMO: 0.01 M, MATE: 0.02 M, DMAEMA: 0.04 M). The morphology of the membrane surface after each modification step is characterized by FESEM. The prepared composite membrane manifests temperature-responsive property. As the temperature rises from 20 °C to 85 °C, the pure water flux of the membrane increases from 68.8 L m-2h−1 to 434.4 L m-2h−1 (0.1 MPa), reflecting a six-fold enhancement. And this temperature response is reversible. In oil-in-dye containing water treatment, the composite membranes demonstrate an oil separation efficiency exceeding 98.0 % and a dye degradation efficiency surpassing 99.0 %. By elevating the ambient temperature, the flux recovery of the composite membrane is 91.2 %, which is much higher than that of the original membrane (58.8 %). This is ascribed to the physical configuration and wettability changes of the grafted polymers at different temperature, which facilitate the release of foulants. This study introduces a novel strategy (surface modification with temperature responsive polymer) for preparing anti-fouling ceramic composite membrane with the function of catalytic degradation of dyes. It would have potential applications in environmental remediation. [ABSTRACT FROM AUTHOR]

• Highly selective Cl−/SO 4 2− separation NF membranes (S = 488) are prepared. • The membrane rejects 99.5% of Na 2 SO 4 , 18.3% of NaCl, with a flux of 9 LMH/bar. • Pore sharpening and increased negativity are realized by a one-step process. • 8″ × 40″ sized modules exhibit good Cl−/SO 4 2− separation performance. • A pilot trial in Sinopec's zero discharge processes is in plan. The petrochemical industry is an important producer of high salinity wastewater, necessitating the efficient separation of salts in zero discharge processes. This study reports the development of an industrially scalable thin film composite nanofiltration membranes that facilitate the effective separation of NaCl/Na 2 SO 4. Employing a one-step functionalization process, the membrane pore distribution is sharpened, and the surface negativity is intensified. Branched polyethyleneimine with abundant reactive amine groups is employed as an aqueous co-monomer, leading to the generation of high density grafting active sites. Nucleophilic substitution reaction is employed to functionalize the membrane surface with negatively charged sulfonic acid groups. Simultaneously, large voids within the free volume are filled and the pore size distribution is effectively narrowed. The resultant membranes demonstrate an impressive rejection of 99.5 % for Na 2 SO 4 , a selectivity of 163.4 for NaCl/Na 2 SO 4 and a selectivity of 488 for Cl−/SO 4 2−, with a water flux of 45 LMH under 0.5 MPa. The corresponding 8″ × 40″ sized spiral wound membrane modules exhibit a NaCl/Na 2 SO 4 selectivity of 100.4 and a Cl−/SO 4 2− selectivity of 258.3, demonstrating high practical applicability. A pilot trial is planned to integrate these novel membrane products into zero discharge processes within the internal chemical enterprises of Sinopec. [ABSTRACT FROM AUTHOR]

[Display omitted] • Surface topology modification was first applied to enhance anti-biofouling in EMBR. • Simply prepared corrugated membrane shows superior anti-biofouling and robustness. • Enhanced shear force and vortices caused by corrugation improve anti-biofouling. • The structural complexity of corrugated topology impedes the formation of biofilm. • Corrugated extractive membrane shows excellent stability in the long-term EMBR. The extractive membrane bioreactor (EMBR) is a prospective method for detoxifying high salinity organic wastewater by integrating a membrane extractive process with a bioreactor. However, uncontrolled biofilm adhesion on the hydrophobic membrane surface could significantly increase its organic transfer resistance. In this work, a novel strategy was proposed to alleviate membrane biofouling by constructing a corrugated topology on the hydrophobic composite extractive membrane. The phenol mass transfer coefficient and anti-biofouling performance of the corrugated composite membrane were evaluated in both side-stream and submerged EMBR configurations. Anti-biofouling assessments of the corrugated composite membrane were conducted in both parallel and vertical orientations. Computational fluid dynamics (CFD) simulations were employed to model the surface fluid behaviours of the membrane. The results revealed that the hydrophobic composite membrane with a corrugated pattern in both orientations exhibited a significantly lower biofouling tendency compared to the flat membrane without any pattern. Following a 14-day continuous submerged EMBR operation, the phenol mass transfer coefficients were only slightly reduced to 90% and 92% of their initial values in parallel and vertical orientations, respectively. The superior anti-biofouling property of the membrane can be attributed to the faster surface flow rate with an enhanced shear force in the parallel mode, effectively removing microorganisms attached to the membrane surface. In the vertical mode, vortices formed in the bottom of the valleys reduce foulant deposition through mixing and scouring. Furthermore, the corrugated topology of hydrophobic composite membrane makes it more challenging for microorganism colonies to attach and form stable biofilms on the membrane surface. [ABSTRACT FROM AUTHOR]

• A sandwich structured composite membrane with synergistic removal of TC by photocatalysis and adsorption was prepared. • The combination of photocatalysis and membrane filtration significantly reduces membrane fouling. • The maximum stress borne of the membrane were improved by 10.58% using polyester-cotton fabric as the supporting layer. • The removal percentage of TC by the composite membrane can reach 87.10% after four cycles. Environmental pollution has become increasingly serious, especially the abuse of tetracycline (TC) antibiotics, which has brought serious problems to human life. Therefore, the residual TC in the environment has become an urgent problem to be solved. To improve the efficiency of TC wastewater purification and solve the problem of powder material recovery during photocatalysis, a sandwich layer photocatalytic composite membrane with catalytic/adsorption synergistic effect was prepared in this study. The first layer of the composite membrane is composed of a polyether sulfone (PES) membrane loaded with UiO-66-NH 2 /Bi 2.15 WO 6 (UN/BWO) photocatalyst (named as UN/BWO@PES), the middle layer is a support layer composed of polyester/cotton fabric, and the lower layer is composed of a calcium alginate/diatomite (CA@DE) membrane with adsorption for TC. Under dark conditions, the rejection percentage of TC by sandwich composite membrane (M4.5 D 0.02-3) can reach 50.81%, while under light conditions, the removal efficiency of TC by M4.5 D 0.02-3 can reach 93.94%. Even after four cycles, the removal percentage of TC by M4.5 D 0.02-3 can still reach 87.10%. Therefore, the visible light responsive photocatalytic composite membrane developed in this study has dual advantages of photocatalysis and membrane adsorption filtration, and has enormous application potential in wastewater treatment, which can minimize membrane pollution and improve the reusability of photocatalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Lignin and GO were synthesized, incorporated in the PSf membrane, and characterized. • The surface charge, hydrophilicity, porosity, and pure water flux improved for lignin/GO composite membranes. • Lignin & GO synergistically achieved 100% Pb2+ & 81% Eosin Y removal. • Freundlich model (n = 2.29) suggests Pb2+ physisorption. • The Langmuir isotherm indicated 71.32 mg/g Pb2+ adsorption. The textile industry uses a variety of lead compounds, including lead acetate for textile dyeing, lead chloride for lead salt manufacture, and lead molybdate for pigments. Furthermore, Eosin Y, a water-soluble red dye, is commonly used in textile dyeing and ink production. The presence of Eosin Y dye and lead metal ions in textile industry effluents is prevalent. Integrating adsorbent nanofillers into the membrane matrix serves a dual purpose of membrane filtration and adsorption functionalities. In this study, Lignin/GO incorporated polysulfone composite membranes were fabricated with the phase inversion method and with PEG 6000 as a pore-forming agent. Zeta potential, pure water flux, mechanical strength, and hydrophilicity of the membranes were all improved by the integration of lignin and GO into the membrane matrix. Filtration operations were carried out using an aqueous solution containing both lead (Pb) and Eosin Y dye. Additionally, the influence of their electrostatic interactions on membrane fouling and the regeneration process was examined. The electrostatic interaction, specifically the linking effect between Pb2+ ions and negatively charged Eosin Y molecules, formed larger Eosin-Pb complexes. This led to an enhanced Pb2+ removal through membrane filtration. During the second filtration cycle, the membrane, comprising 0.75 wt% lignin and 0.75 wt% GO, achieved 100 % removal of Pb2+ ions and an 81 % rejection of Eosin Y. A Pb2+ adsorption study was conducted using the optimized lignin/GO membrane. The adsorption process was investigated through Langmuir and Freundlich isotherms exhibiting a superior fit and assured R2 values of 0.977 and 0.994, respectively. According to the isotherm data the adsorption process involves multilayer physisorption. The developed Lignin/GO-incorporated polysulfone composite membranes hold the promise for tackling issues in a variety of domains, including water treatment and biomedical applications, demonstrating versatility and ability to make positive impacts across industries. [ABSTRACT FROM AUTHOR]

• Defect–free, ordered COF composite membranes was prepared by the improved IP process. • Monomers synthesis process and self–assembly of the oligomers were decoupled. • Self-assembly of the oligomers occurs on the support surface without being disturbed. • The TpPa–II/PMIA composite membrane exhibited excellent dye separation performance. • It maintains both its performance and structural stability in long-term filtration. Covalent organic frameworks (COFs) are crystalline porous materials composed of organic building blocks linked by covalent bonds, which have attracted great attention for membrane–based separation applications. However, fabrication of COF membranes with high quality and performance remains a challenge, especially for the β –ketoenamine linked COFs. In the conventional IP methods, the synthesis process (the Schiff–base reaction of the monomers and the tautomerism of the oligomers) and the crystallization process (the self–assembly of the oligomers) of the COFs materials occur simultaneously on the surface of the support membrane, which can result in low crystallinity, high defect density, and poor separation performance of the COF layer. In this study, a novel strategy for fabricating large-area, defect–free COFs composite membranes by interfacial polymerization (IP) was presented to overcome this problem. By incorporating both the amine and aldehyde monomers in one organic phase, and dissolving organic acid catalyst in another phase (the water), the synthesis process mostly take place in the bulk of the organic phase, while the crystallization occurs on the surface of the support membrane under the influence of the organic acid catalyst. This strategy effectively decoupled the synthesis process with the crystallization, providing a stable growth region for crystalline layer, ultimately leading to the formation of a thin, defect–free and highly ordered COF layer on the support membrane. The strategy was demonstrate by synthesis of triformylphloroglucinol phenylenediamine (TpPa)–Ⅱ/Poly(m–phenylene isophthalaminde) (PMIA) composite membrane. We characterize the structure and morphology of the TpPa–Ⅱ/PMIA composite membrane by various analytical techniques to verify our hypothesis, and evaluate its separation performance using pure water permeance and dyes retention rate as indicators. The results show that the TpPa–Ⅱ/PMIA composite membrane has an 80 nm thick top-layer with regular COF structure and orderly pores. It exhibits an excellent dye separation performance, with a (pure water permeance) PWP of 105.6 L·m−2·h−1·bar−1 and CR rejection of 99.2 %, which surpasses most of the TpPa–type COFs composite membranes reported in literature, as well as the reference (TpPa–I/PMIA membrane) in this work. Moreover, the TpPa–Ⅱ/PMIA composite membrane maintains both its performance and structural stability during a 240–hour cross–flow filtration of the dye solution, demonstrating its excellent potential in the dye wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A superhydrophobic composite membrane based on CNTs network was constructed. • CNTs networks can provide many active sites for perfluorination modification. • CNTs network endows membrane surface with slippery characteristics and reduced surface pore size. • Superhydrophobic composite membranes possess excellent water vapor flux and wetting resistance. Enhancing the wetting resistance of the membrane is crucial for consolidating the stability of the membrane distillation (MD) process, but this generally leads to the decline of water vapor flux. Herein, we developed a superhydrophobic composite membrane composed of a highly hydrophobic polyvinylidene fluoride (PVDF) porous support layer and a functional superhydrophobic carbon nanotubes (CNTs) network. The CNTs network with high thermal conductivity not only reduces the temperature polarization effect, but also increases the effective evaporation area, thereby enhancing the mass transfer driving force of the MD process. Additionally, the CNTs network significantly reduces the maximum pore radius of the composite membrane, and the perfluorination treatment also reduces the surface energy of the CNTs network, thereby synergistically increasing the liquid entry pressure. The results showed that when treating high salinity water containing 3.5 wt% NaCl, the water vapor flux of the composite membrane increased from 20.0 LMH of the original PVDF membrane to 24.4 LMH, an increase of 22 %. Furthermore, the performance of the original PVDF membrane deteriorates rapidly when the concentration of surfactant in the feed exceeds 1.0 mM, while the composite membrane still maintains a stable water vapor permeability and salt rejection. More importantly, the composite membrane exhibits excellent resistance to wetting induced by gypsum scaling when using gypsum solution as the feed, which is attributed to its small surface pore size and high hydrophobicity. This research supplies new insights into the design of membrane structures used in MD processes to overcome the trade-off between water vapor permeability and wetting resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of novel chiral hyper-crosslinked polymer composite membranes (CHCPs/PSS) were fabricated by surface-initiated Friedel-Crafts alkylation reaction on the porous SiO 2 substrate. • The resulting chiral hyper-crosslinked polymers showed a micro/mesoporous morphology, high BET surface areas and good thermal and chemical stability. • The membrane fabrication conditions were optimized, the percent enantiomeric excess (ee%) and permeability reached 91.2 %, 6.31 × 10−2 m2/h for phenylalanine and 24.4 %, 1.56 m2/h for ibuprofen, respectively. • Static adsorption and quantum chemical computation proved that the adsorption energy difference between the chiral polymer and enantiomers results in the effective separation. With the rapid development of the pharmaceutical industry, efficient enantiomeric resolution is of great significance for the preparation of single enantiomer drugs. Herein, several kinds of chiral hyper-crosslinked polymer composite membranes (CHCPs/PSS) were fabricated by surface-initiated Friedel-crafts alkylation reaction on the porous SiO 2 substrate for enantioseparation. The membrane fabrication conditions were optimized by changing various monomer concentrations, polymerization times and substrate pore sizes using phenylalanine as separated substance and the percent enantiomeric excess (ee%) reached 91.2 % with a permeability up to 6.31 × 10−2 m2/h which was 1012 folders higher than the traditional chiral polymer membranes. Besides, the enantioseparation of disparate enantiomers including clinical drug were also evaluated using CHCPs/PSS membranes to expand its application scope. The ee% and permeability reached 9.48 % and 5.13 × 10−1 m2/h for tryptophan and 24.4 % and 1.56 m2/h for ibuprofen, respectively. Static adsorption and quantum chemical computation were utilized to analyze the separation mechanism and the results indicated that the adsorption energy difference which resulted from the multiple interactions contributed to the effective separation of enantiomers. Consequently, this work will provide a new method for the application of chiral hyper-crosslinked polymer membranes in enantiomeric separation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of COFs modified Nylon microfiltration substrates by interfacial polymerization. • The COFs layer has an impact on subsequent IP processes confirmed by MD simulation. • The polyester layer has hydrophilicity and anti-fouling properties. • The COF-PE/Nylon membrane shows excellent separation performance. Currently, polyester (PE) membranes prepared using green materials have gained more attention in the membrane separation field. Most of the previously reported PE membranes are synthesized on ultrafiltration substrate, which hinders the enhancement of water permeance. This paper proposes a new strategy to fabricate PE membranes with covalent organic frameworks (COFs) modified microfiltration substrate via interfacial polymerization (IP). On the one hand, COFs modify the Nylon microfiltration substrate while affecting the subsequent IP process to obtain the thinner and smoother selective layer. This process was also analyzed by molecular dynamics (MD) simulation. On the other hand, the excellent hydrophilicity of the PE layer also endowed the anti-fouling properties of the covalent organic frameworks-polyester/Nylon (COF-PE/Nylon) membrane. The optimal COF-PE/Nylon membrane had 99.6 % Congo red (CR) rejection, and dye/salt (CR/NaCl) selectivity was 63.1. Meanwhile, the pure water permeance reached 157.5 L m−2h−1 bar−1, higher than the PE membrane prepared on the ultrafiltration substrate. The present work demonstrated the excellent separation performance of COF-PE/Nylon membranes and provided a reference for subsequent PE membrane preparation on various substrates. [ABSTRACT FROM AUTHOR]

[Display omitted] • Waste PVC pipe was successfully upcycled into an ultrafiltration support membrane. • The polyamide layer was synthesized atop the Upcycled PVC support via IP. • Additives in PVC pipe influenced the properties of the support and selective layers. • Upcycled PVC TFC exhibited performance on par with the commercial PES TFC membrane. Thin-film-composite (TFC) nanofiltration membranes represent the pinnacle of membrane technology in water treatment and desalination. These membranes typically consist of a polyamide (PA) selective layer and a membrane support layer, often constructed from commercially available materials like polyethersulfone (PES). However, there exists an alternative approach that involves the use of different polymers, preferably upcycled waste polymers, as a viable support layer for TFC membranes. Successfully implementing the upcycling of waste plastics into high-value support membranes can make a significant contribution to addressing the issue of plastic waste pollution. One of the primary challenges associated with utilizing upcycled polymers as support layers is the potential impact on the polyamide selective layer of TFC membranes, subsequently affecting their performance in terms of permeability, rejection, and antifouling properties. In this study, we demonstrate the successful fabrication of TFC membranes with a support layer crafted from upcycled waste PVC pipe. We conducted a comprehensive investigation into the effects of upcycled PVC on the structural and physicochemical properties of the polyamide layer. The ultrafiltration (UF) support membranes were fabricated from waste PVC pipe via the nonsolvent induced phase separation (NIPS) method. Subsequently, a polyamide layer was synthesized atop the Upcycled PVC membrane using interfacial polymerization (IP). The physicochemical properties and performance of the TFC membranes with upcycled PVC support layer were compared with membranes with research-grade (RG) PVC and commercial PES support layers. The results unveiled that the TFC membrane with upcycled PVC support layer exhibited higher water permeability (18.2 LMH/bar), in contrast to RG TFC (15.5 LMH/bar) and PES TFC membranes (13.7 LMH/bar). Furthermore, the salt rejection capabilities of the upcycled PVC TFC membrane were competitive and well within an acceptable range. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrically active nanofiltration membranes with ultra-thin MXene separation layer are developed. • The thickness of the MXene separation layer is about ∼47 nm. • CNT/MXene-PEI membrane exhibited superior permeate fluxes, high dye rejection and excellent inorganic salt penetration under electric field. • The membrane showed good antifouling ability and long-term stability for dye/salt mixture solution separation. Two-dimensional MXene membranes have garnered significant attention in the field of water treatment. Nevertheless, achieving a balance between permeability and selectivity remains a fundamental challenge in MXene membrane separation. Herein, a novel electrically active nanofiltration (NF) membrane (CNT/MXene-PEI) with an ultra-thin separation layer was prepared through vacuum filtration of MXene and cross-linking of polyethyleneimine (PEI) on the CNT substrate. By controlling the thickness of the MXene separation layer to reduce mass transfer resistance and applying a negative voltage to enhance the electrostatic effect between the conductive membrane and charged pollutants, the dye rejection rate and anti-pollution performance were improved. At an optimal MXene loading of 15.625 mg/m2, the thickness of the separation layer was about ∼47 nm. Under these conditions, the pure water flux achieved was 156.11 LMH/bar. The rejection rate of methylene blue (MLB) increased from 26.2 % to 97.9 % under an applied voltage of −2 V, while the rejection rate for inorganic salts was 9 %. The dye/salt separation factor was approximately 11. Furthermore, the flux recovery rate of the CNT/MXene-PEI membrane was at 90 % after 12 h of operation with applied voltage of −2 V, indicating excellent anti-pollution performance and long-term operational stability. These results demonstrate the combined effect of structural regulation and electric field enhancement in the membrane's filtration performance. This study offers a new approach for overcoming the trade-off effect between permeability and selectivity in dye/salt separation processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Facile fabrication of composite nanofiber membrane for Congo Red dye removal with antimicrobial performance. • Demonstrated 94.5 dye removal effeciency, stability, and reusability. • Achieved 99 % bacterial reduction capability at a high permeation flux. • The implication of composite membrane as an ideal choice for water treatment, particularly in developing countries. This research presents a novel and efficient process for Congo Ced (CR) dye removal together with exceptional antimicrobial performance using a dual-functional composite membrane. The membrane fabrication involves the electro-spun infusion of cuprammonium cellulose solution with polyethylene oxide (PEO) and polyacrylonitrile (PAN) in a conjugated fashion. The composite membrane exhibits 94.0 % dye removal capability and 41 mg/g adsorption capacity. The adsorption kinetics was proved to conform to the pseudo-second-order (PSO) model, and the equilibrium adsorption results were accurately defined by the Dubinin-Radushkevich model, indicating the process of adsorption as a physical, exothermic interaction that occurs spontaneously. The dye removal efficacy of the membrane in the first and fifth usage was 94.5 and 84.2 %, respectively, demonstrating its effectiveness, stability, and reusability. The composite membrane also exhibited effective antibacterial performance regarding Staphylococcus Aureus and Escherichia Coli (S. aureus & E. coli) with 99 % bacterial reduction capability at high permeation flux of ∼13,000 L m−2h−1. Hence, the fibrous composite materials demonstrated its potential to be an ideal choice for water treatment in textile mills, especially in developing countries. [ABSTRACT FROM AUTHOR]

[Display omitted] The use of metal–organic frameworks (MOFs) in gas separation has been widely explored. However, the stabilities are poor in various practical applications, especially under humid conditions. In this work, water-stable UiO-66-(CF 3) 2 was prepared by grafting with trifluoromethyl groups. On this basis, mixed matrix membranes (MMMs) containing different UiO-66-(CF 3) 2 loadings in PIM-1 were fabricated. When the UiO-66-(CF 3) 2 loading was increased from 0 to 8 %, the CO 2 permeability of the membrane increased from 3265 to 5242 Barrer, and the CO 2 /N 2 selectivity improved from 24.2 to 33.8. Meanwhile, we prepared the PIM-UF/PDMS/PSf (PUPP) composite membranes and applied for CO 2 /N 2 separation under humid conditions. Specifically, PUPP-8 % exhibited a permeability of 1111 GPU and a competitive CO 2 /N 2 separation factor of 43.78 under the simulated flue gas environment (57 °C, 0.1 MPa, 10 vol% H 2 O), which transcended the 2008 upper bound. Finally, we studied the long-term gas permeability to simulate the real flue gas environment, and the PUPP-8 % water content test conditions maintained its structure and performance, benefiting from good water stability. These results demonstrated that improving the water stability of MOFs and developing high-performance membranes for stabilization in high-humidity environments is a potentially effective strategy. [ABSTRACT FROM AUTHOR]

[Display omitted] • PTFE/ceramic membranes were efficiently prepared via the solid-state sintering method. • PVA was employed as a binder to facilitate the creation of the hydrophobic PTFE layer. • The prepared composite membranes exhibited a fine and narrow pore structure. • The hydrophobic membranes exhibited good performance in filtering water-in-oil emulsions. The surface wettability and pore structure of membranes play crucial roles in determining their separation efficiency. Innovating ceramic membranes with hydrophobic surfaces holds considerable promise for broadening their applications. Owing to the remarkable hydrophobic properties and robustness of PTFE materials, this study suggests the fabrication of PTFE/ceramic composite membranes utilizing a solid-state sintering of PTFE nanoparticles. Polyvinyl alcohol (PVA) was employed as a binding agent to facilitate the formation of a uniform PTFE membrane layer on the porous ceramic substrate. A comprehensive investigation was conducted into the influence of various factors, including PVA addition, emulsion concentration, dip-coating duration, and sintering temperature, on the morphology and performance of these composite membranes. The results showed that the incorporation of PVA effectively mitigated the back-diffusion of PTFE particles and ensured the structural integrity of membrane. The resulting PTFE/ceramic membrane exhibited a finer and more uniform pore structure than the commercial PTFE membrane. The composite membrane boasted a water contact angle of 133°, an average pore size of 78 nm, and a membrane layer thickness of 3.8 μm. These characteristics contributed to its exceptional separation performance when utilized in the ultrafiltration of polystyrene nanoparticle suspensions and the androstenedione-contained water-in-oil emulsion. [ABSTRACT FROM AUTHOR]

• A mild one-step fabrication method of cross-linked GO membrane was proposed. • DA/PEI modification improved the structures and performances of GO membranes. • Flux and rejection simultaneously enhanced for removing heavy metal ions. • GO@DA/PEI 40 membrane exhibited superior anti-fouling performance and stability. Heavy metal ion contamination poses a significant threat to both our environment and human health. Consequently, there is a need for proficient and environmentally friendly remediation techniques to tackle this issue. Among various strategies, membrane-based separation using graphene oxide (GO) laminate membranes has emerged as a promising solution. However, traditional GO membranes have low water permeance, poor selectivity, structural instability, and inconsistent layer spacing. In this study, we cross-linked GO with polydopamine/polyethyleneimine (DA/PEI) using a mild one-step strategy to prepare a GO@DA/PEI membrane for heavy metal ion removal and evaluated the effect of cross-linking duration on the interlayer structure, membrane properties, and heavy metal ion removal performance. The successful formation of a cross-linked network between DA/PEI and GO was proven by various characterization methods. Compared with previously reported GO-based membranes, the prepared GO@DA/PEI 40 membrane exhibited excellent performance, including a peak pure water flux of 326.7 L/m2h and ion rejection of 99.6 % for Cu2+, 93.5 % for Pb2+, and 96.6 % for Zn2+, thereby overcoming the conventional trade-off" effect. The mechanism for the high flux was discussed. The cross-linking reaction between the oxygen-containing functional groups at the edges and basal planes of the GO flakes and DA/PEI were crucial to the high flux. In addition, the GO@DA/PEI 40 membrane had excellent anti-fouling performance in the presence of humic acid and long-term stability under different conditions. Overall, the GO@DA/PEI membrane has good potential for heavy metal ion removal. [ABSTRACT FROM AUTHOR]

[Display omitted] • Surface dynamics was utilized to generate a selective layer on ISA membranes. • The thermally treated polyimide ISA membranes evolved from UF to NF. • Relationships between the formed skin and the initial pore structure were studied. • The developed polyimide membranes were competitive in OSN. Integrally-skinned asymmetric (ISA) polymer membranes show enormous potential in efficiently energy-saving organic solvent nanofiltration (OSN) due to their excellent structural stability. However, the control of their microstructures at the nanoscale is technically challenging, making it difficult to simultaneously achieve high separation resolution and high solvent permeance. In this work, we report the in-situ evolution of polyimide ISA membranes from ultrafiltration to nanofiltration through thermal-induced densification of the surfaces. This process was attributed to the surface dynamics of polymers — i.e., the polymer segments on surface are more freely movable than that in bulk. The optimum treatment temperature was located between the glass transition temperatures of surface and bulk, which were measured based on porosity changes. The as-prepared ISA membranes with thin and dense skin layers exhibited high solvent permeance (e.g., over 5 L m−2 h−1 bar−1 for ethanol) and favorable molecular weight cut-off of around 300 Da. The membranes rivaled the state-of-the-art thin film composite membranes, demonstrating great potential in fast and precise molecular separation in OSN. [ABSTRACT FROM AUTHOR]

[Display omitted] • Different surfactants precisely regulate the diffusion rate of Cyclen monomer. • TFC membranes with different surfactants have customized pore size distributions. • TFC membrane enables on-demand desalting and antibiotic/salt separation. • TFC membrane has great application potential in antibiotic/salt separation. The diffusion of amine monomer during interfacial polymerization (IP) directly affects the structure and properties of the polyamide (PA) separation layer. Surfactants can regulate the diffusion rate of monomers and change the microstructure of the PA layer. In this study, a PA nanofiltration (NF) membrane with the tailor-made pore size is fabricated by modulating the diffusion rate of 1, 4, 7, 10-tetraazacyclododecane (Cyclen). Surfactants with different alkyl chain lengths are used to precisely regulate the diffusion rate of Cyclen monomer. The longer the alkyl chain length of the surfactant is, the faster the diffusion rate of the Cyclen monomer is, resulting in the formation of a PA layer with a narrow pore size distribution. The prepared composite membrane is qualified for on-demand desalting and antibiotic/salt separation performance by changing the length of the alkyl chain. For example, surfactants with short alkane chains (C 4) endow the NF membranes with a high water permeance of 30.7 L−1 m−2h−1 bar−1 for tetracycline separation. Surfactants with long alkane chains (C 12) endow the NF membranes with a high selectivity of 84.8 for tetracycline/NaCl separation. This study provides further evidence for surfactant-regulated IP reactions and offers new ideas for the tailor-made regulation of NF membrane properties. [ABSTRACT FROM AUTHOR]

• PNIPAm-based HCM with cavitands as nanocontainers was developed for protein absorption. • The hydrogel structure is modified by cavitands and validated by MD simulation. • Fabricated HCM exhibits good structural stability and robust BSA separation performance. Protein adsorption is of great significance for bioengineering, biomedicine, drug release, etc. Herein, poly- N -isopropylacrylamide (PNIPAm) and polyethylene glycol diacrylate (PEGDA) based hydrogel materials were used to introduce self-synthesized cavitands with pore cage structures and hydrophobic characteristics to construct high-efficiency hydrogel composite membrane (HCM) for the adsorption of bovine serum albumin (BSA). The hydrophobic cavitand cage can improve the interfacial polymerization process by impacting the monomer diffusion and then modifying the interface properties of the hydrogel molecular network, which is validated by the molecular dynamic simulation. The adsorption mechanism can be interpreted as the reorganization of the polymer pores using the cavitands, and hence the surface charge and hydrophobic property consequently changed, which is consistent with the measurement results as well as validated by the molecular dynamic simulation. Thus, the fabricated HCM exhibits good structural stability, thermal stability, and robust BSA adsorption performance. The results indicated that the developed HCM materials can be promising candidates for effective protein separation. [ABSTRACT FROM AUTHOR]

[Display omitted] • PS/PAN-PVDF/PDMS@Fe 3 O 4 /TiO 2 composite membranes with superhydrophobicity and lipophilicity were prepared by one-step electrospinning technology. • The surface wettability of the composite membrane undergoes dynamic changes through alternating cycles of UV irradiation and heating. • PS/PAN-PVDF/PDMS@ Fe 3 O 4 /TiO 2 Excellent magnetic attraction and magnetic recycling ability. • PS/PAN-PVDF/PDMS@Fe 3 O 4 /TiO 2 composite membrane with excellent anti-fouling and photocatalytic ability. • PS/PAN-PVDF/PDMS@Fe 3 O 4 /TiO 2 composite membranes exhibit stable oil–water separation and cycle life. Developing multifunctional separation membranes, especially composite separation membranes that are corrosion-resistant, fouling-resistant, and easy to collect, has become a new challenge to treating oily wastewater in complex environments. Therefore, superhydrophobic magnetic membranes composed of polystyrene/poly(acrylonitrile)-poly(vinylidene fluoride)/poly(dimethylsiloxane)-iron oxide/titanium dioxide nanoparticles (PS/PAN-PVDF/PDMS@Fe 3 O 4 /TiO 2), which possess exceptional corrosion resistance and UV absorption properties, were fabricated through the process of electrospinning. Controlling the doping ratio of Fe 3 O 4 /TiO 2 , composite membranes with excellent superhydrophobicity (156.9°), mechanical properties (3.67 MPa and 75.93 %), and thermal stability (330 °C) were obtained. The membrane demonstrates outstanding corrosion resistance (WCA > 150°) even after being immersed in various corrosive solutions for 120 h. Under visible-ultraviolet irradiation, the membrane has excellent UV absorption and exhibits a significant red-shift phenomenon, providing a certain degree of resistance to fouling. In the presence of a magnetic field, the membrane has a maximum saturation magnetization of 9.98 emu/g, which the magnetic field drive can attract. The oil adsorption capacity of the membrane was 29–112 g/g, which also maintained 88 % of the initial value after ten cycles. In addition, a comprehensive evaluation was conducted to assess the fabricated composite membrane's separation flux, efficiency, and cycle life when exposed to acidic and alkaline corrosive solutions. The results indicated that even after 40 cycles, the membrane's oil–water separation flux and separation efficiency remained at 6971 L.h−1.m−2 and 97 %, respectively, representing a 24.2 % increase compared to the unmodified membrane. Therefore, the membrane exhibits promising potential for treating oily wastewater in harsh environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • First-time utilization of macrocyclic Noria to prepare porous organic polymer membrane. • High performance membrane can be formed in just 7 min under mild conditions. • Noria-o-POP-7 membranes with unique structure show a superior water permeance. • The optimal membranes also show a good separation performance in organic solvent. Porous organic polymers (POPs) have become a promising option for creating innovative membranes due to their desirable characteristics such as high porosity, stability, well-defined pore size, and adjustable structure. Utilizing macrocyclic molecules as reaction monomers to tailor POP membranes holds great potential. For example, their hollow inner cavities and abundant chemistry groups can bring surprising performance enhancements to membranes. In this study, the double-cyclic ladder-type molecule Noria was employed as a reactive monomer to prepare o-POP (o-hydroxyazo porous organic polymers) membranes. Compared to o-POP membranes prepared with conventional monomers, Noria-o-POP composite membranes exhibited superior separation performance. The optimal Noria-o-POP-7 composite membrane possesses a pure water permeance of 95.3 L·m−2·h−1·bar−1 and 99.8 % rejection for methyl blue. This can be rationalized by the highly porous network structure and the good sieving effect of double-cyclic cavities that stem from Noria. Beyond that, the Noria-o-POP-7 composite membranes also exhibited excellent performance in ethanol (permeance: 63.5 L·m−2·h−1·bar−1, rejection for EB in ethanol: 97.5 %). This work not only demonstrates the feasibility of using the macrocyclic molecule Noria in preparing o-POP membranes but also offers new insights into the development of high-performance o-POP membranes. [ABSTRACT FROM AUTHOR]

[Display omitted] • PDMS coating thickness is optimized to 376 nm under comprehensive consideration. • The ultimate samples behaved excellent with J O2 = 502 GPU and J CO2 = 4117 GPU. • Hemocompatible tannic acid layer is deposited continuously by Fe(III) chelation. • Membrane area can be saved by about 90 % for general extracorporeal oxygenation. • The increase in permeation successfully neutralized the lacking in selectivity. Artificial lung membranes are the heart for extracorporeal oxygenation. Hereinto, the nonporous PDMS-based membranes have excellent biocompatibility, and also isolation ability to both blood and harmful matters. Nevertheless, their CO 2 /O 2 selectivity, in the conventional cases using pure-oxygen sweeping stream, is not enough to accomplish sufficient CO 2 removal in balance with O 2 addition. In this work, the oxygenation mode using oxygen-enriched stream, faithfully based on the permeation mechanism, is established to overcome this bottleneck. To neutralize the negative impacts caused by lowering oxygen content and its partial pressure, PDMS-based composite membranes with ultra-thin selective layer to enhance mass transfer have been fabricated successfully. The experiments manifest that the selective layer, on the basic condition that the composite structure is stable enough to make surface modification and realistic utilization, is decreased to 376 nm on the porous substrates. O 2 and CO 2 permeation rates through the ultimate membrane samples have been enhanced to 502 GPU and 4117 GPU, respectively. In this instance, the essential oxygenation could be sustained with O 2 partial pressure less than 446 mmHg in the sweeping stream. The minimum membrane area for a common treatment case is 0.05 square meters. Once the membrane area is increased to 0.18 square meters, the sterile air after purification could be directly used for oxygenation. In comparison to the oxygenation devices being used currently, membrane area can be saved by about 90 %, which is highly significant to reduce the injuring influence on blood cells. All in all, the artificial lung membranes with ultra-thin PDMS coating layer have promising future in realistic utilization. [ABSTRACT FROM AUTHOR]

• Electrostatic spraying was firstly used in COF-LZU1 formation on membrane substrate. • Membrane fouling behavior in DCMD for different ECs was systematically investigated. • COF-based membrane performance in temperature changing DCMD process was studied. Emerging contaminants (ECs) in aqueous ecosystem are becoming a global threat to human beings, which are mainly discharged from industrial wastewater. Direct contact membrane distillation (DCMD) can utilize waste heat to treat industrial wastewater containing ECs, achieving a better balance between removal efficiency and operation cost than other technologies. However, membrane fouling is the major obstacle that impedes DCMD application. Therefore, anti-fouling covalent organic framework COF-LZU1/PVDF composite membranes were prepared via electrostatic spraying and used in DCMD for the first time. Four typical EC compounds (ibuprofen, acesulfame, sulfamethoxazole, and N,N-diethyl-3-methylbenzamide) were selected as targets to investigate the effect of water affinity and charge on membrane fouling. Results showed that COF-1.0 membrane with relatively hydrophilic COF-LZU1 structure exhibited higher permeate flux and salt rejection than commercial PVDF substrate when treating sulfamethoxazole and ibuprofen within pH range of 4–7 and temperature of 40–70 °C. This could be attributed to the weaker hydrophobicity and closer-to-neutral zeta potential of COF-1.0, which weakened the electrostatic and hydrophobic-hydrophobic interactions between membrane and ECs. In addition, the membrane performance comparison in temperature changing DCMD process further showed that COF-1.0 performed better in terms of permeate flux, especially in the gradually decreased temperature condition. Overall, these findings would advance the fundamental understanding and practical application of COF-based membranes in DCMD for ECs treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A solution-free melt coating method (MM) was used to fabricate dense membranes. • Poly(ether-block-amide) (PEBA) membranes fabricated using MM possess high crystallinity. • Composite and freestanding membranes fabricated by MM showed similar performance. • A separation factor of 74 was achieved by the 11 μm thick PEBA composite membrane. Solution-based membrane fabrication methods, which are widely used in the membrane industry, have a negative impact on the environment and fabrication effectiveness. In this study, a green solution-free melt coating method was proposed to rapidly fabricate a poly(ether-block-amide) copolymer (PEBA) composite membrane. Based on its melting point and viscosity, PEBA 1074 was chosen as a suitable membrane material for fabrication by solution coating and melt coating methods, which were compared by characterizations such as variable-temperature synchrotron X-ray diffraction and nano-scratching test to reveal the differences in such as crystallinity etc. The separation performance of these membranes for the pervaporation of phenol from aqueous solutions under different operating conditions was evaluated. The results showed that the PEBA composite membrane fabricated by the melt coating method possessed the same separation factor as the corresponding freestanding membrane because the sol-gel transition was avoided, and a separation factor of 74 for the separation of 1.5 wt% phenol/water solution at 70 °C can be obtained due to high density and crystallinity even with a thickness of 11 μm, which is superior to previously reported results. This study provides an ecologically friendly and effective approach for the fabrication of thermoplastic polymer membranes, thereby promoting their industrial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • TiO 2 -SiO 2 -OCL (organic chelating ligands) composite membranes were fabricated for application to pervaporation dehydration. • Changing pore sizes and hydrophobicity of TiO 2 -SiO 2 membranes using OCL and firing conditions. • Hydrophilic properties and large pores improved permeance and separation in PV dehydration. Microporous TiO 2 -SiO 2 composite membranes intended for use in the pervaporation dehydration of a water/isopropanol mixture were prepared via the sol–gel method using acetylacetone (ACA) as an organic chelating ligand (OCL). TiO 2 -SiO 2 -ACA sols were prepared by using titanium (IV) propoxide (TiTP), an alkoxide of Ti, tetraorthoethylsilicate (TEOS), an alkoxide of Si, and ACA, as a composite of TiO 2 and SiO 2 with coordinating OCL to Ti. The dried gels were fired at 300 °C under N 2 or at 500 °C under air, and were analyzed via FT-IR. Both powders had Ti-O-Si bonds, however, OCL in the powder fired at 500 °C in air has decomposed and removed. The TiO 2 -SiO 2 -ACA sols were applied to alumina plates and fired at either 300 °C under N 2 or at 500 °C under air to check the water-contact angle, which indicated that the OCL was retained on the plates fired at 300 °C under N 2 and were more hydrophobic than when fired at 500 °C under air. TiO 2 -SiO 2 -ACA composite membranes were fabricated by coating either the TiO 2 -SiO 2 -ACA sol layer fired at 300 °C under N 2 or that fired at 500 °C under air onto a TiO 2 -SiO 2 intermediate layer with an α-alumina support. The pore sizes of both membranes were estimated via the NKP method for single-gas permeance at 200 °C. The mean pore sizes of the membranes fired under N 2 at 300 °C and under air at 500 °C were 0.47 nm and 0.68 nm, respectively, which suggested the possibility of pore size control via firing conditions. Pervaporation tests of the TiO 2 -SiO 2 -ACA composite membranes in a water/isopropanol mixture (IPA: 90 wt%) showed that the membranes fired under air at 500 °C and under N 2 at 300 °C had values for permeation flux of 0.90 and 0.13 kg/(m2 h) and separation factors of 667 and 98 at 50 °C, respectively. The higher permeation flux of the membrane fired under air at 500 °C was due to the influence of a larger pore size as well as to a more hydrophilic surface. On the other hand, the separation factor was also higher for the membrane fired under air at 500 °C, because the hydrophilic surface facilitated water permeation. These results indicate the possibility of using firing conditions to control both the pore size and the surface properties of microporous TiO 2 -SiO 2 -ACA composite membranes for use in PV separation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amino-functionalized polyethylene-silica (APS) composite membranes were fabricated. • Silica loading rate was tunable and reusability of APS after 7 washes was over 99%. • Formate dehydrogenase (FDH) immobilized on APS showed greatly enhanced activity. • Reusability was much improved compared to particles or membrane attached FDH. Enzymatic CO 2 conversion represents a highly efficient, energy-conserving, and environmentally sustainable approach to mitigating the increasing pressure caused by huge carbon emissions and generating valuable products. However, several challenges associate with the process including the instability and recovery difficulty of free enzyme, as well as low solubility of CO 2 in mild conditions. Immobilizing enzyme on the amino-functionalized supports presents a viable solution to these issues. Considering the wide application of polymer hollow fiber membranes in the field of CO 2 gas–liquid membrane contactor and the characteristics of hydrophilic, biocompatible, and high specific surface area of silica nanoparticles, the amino-functionalized polyethylene (PE)-silica (APS) composite membranes were fabricated via different routes. The morphologies, the loading rates of modified SiO 2 and reusability of APS membranes were characterized for a crude screening. Following that, seven kinds of APS membranes were used as the carriers of formate dehydrogenase (FDH) that could catalyze the reduction of CO 2 to formate, and their immobilization efficiency and catalytic performance were compared. The results show that 1# and 2# membranes based on carboxyl-modified PE with a loading rate of 5.5 %∼5.6 % and the reusability of above 99 % were more ideal carriers than others. The enzyme activity recovery rate of APS-immobilized FDH (FDH-APS) was separately 367 % and 256 %, proving the intensification action of carriers on the enzymatic reaction. After 10 cycles of use, the relative activity of two kinds of FDH-APS was around 70 % and 78 %, much higher than corresponding particles or membrane attached FDH (25.3 % and 20.4 %). After storage at 4 °C for 20 days, the relative activity of FDH-APS was 82.7 % and 81.0 %, while it was only 61.4 % for free enzyme. [ABSTRACT FROM AUTHOR]

Herein, we successfully fabricate Co SACs supported on CNT/MoS 2 heterojunction nanocomposite (Co 1 -MoS 2 /CNT) by a hydrothermal synthesis combined with the subsequent impregnation method. The catalytic performance of Co 1 -MoS 2 /CNT is evaluated using the reduction of 4-NP in an aqueous media containing sodium borohydride. Complete reduction of 4-NP catalyzed by Co 1 -MoS 2 /CNT occurs within 5 min at room temperature, and the apparent rate constant k can reach 1.16 min−1, which is 4.1 and 38.6 times higher than those of Co 1 -CNT and Co 1 -MoS 2 , respectively. The improved catalytic performance of Co 1 -MoS 2 /CNT is attributed to the p-n heterojunctions of MoS 2 /CNT increasing the electron density of the Co single-atom sites, as well as the CNTs with excellent conductivity, accelerating the electron transfer. Moreover, Co 1 -MoS 2 /CNT exhibits excellent stability and favorable applicability, endowing its potential for practical applications. Our findings not only provide useful insights into the enhancement of catalytic performance of SACs, but also open a new avenue for the treatment of 4-NP wastewater. [Display omitted] • Successful synthesis of Co SACs supported on CNT/MoS 2 heterojunction nanocomposite. • p-n heterojunctions of MoS 2 /CNT increase the electron density of Co single-atom sites. • Complete reduction of 4-NP catalyzed by Co 1 -MoS 2 /CNT occurs within 5 min at room temperature. • Apparent rate constant k of Co 1 -MoS 2 /CNT is 4.1 and 38.6 times higher than those of Co 1 -CNT and Co 1 -MoS 2 , respectively. • Co 1 -MoS 2 /CNT exhibits excellent stability and favorable applicability, endowing potential for practical application. Modulation of the electronic structure of heterogeneous catalysts by introducing heterojunctions is an effective means to improve their catalytic performance. Although Co-based nanocatalysts have been widely used in the reduction of 4-nitrophenol (4-NP) wastewater, Co single-atom catalysts (SACs) have rarely been reported. Herein, we successfully fabricate Co SACs supported on CNT/MoS 2 heterojunction nanocomposite (Co 1 -MoS 2 /CNT) by a hydrothermal synthesis combined with the subsequent impregnation method. The catalytic performance of Co 1 -MoS 2 /CNT is evaluated using the reduction of 4-NP in an aqueous media containing sodium borohydride. Complete reduction of 4-NP catalyzed by Co1-MoS 2 /CNT occurs within 5 min at room temperature, and the apparent rate constant k can reach 1.16 min−1, which is 4.1 and 38.6 times higher than those of Co 1 -CNT and Co 1 -MoS 2 , respectively. The improved catalytic performance of Co 1 -MoS 2 /CNT is attributed to the p-n heterojunctions of MoS 2 /CNT increasing the electron density of the Co single-atom sites, as well as the CNTs with excellent conductivity, accelerating the electron transfer. Moreover, Co 1 -MoS 2 /CNT exhibits excellent stability and favorable applicability, endowing its potential for practical applications. Our findings not only provide useful insights into the enhancement of catalytic performance of SACs, but also open a new avenue for the treatment of 4-NP wastewater. [ABSTRACT FROM AUTHOR]

Organic solvent forward osmosis (OSFO) as a promising separation process for the pharmaceutical industry. The practicality and suitability of OSFO membrane are significant for the OSFO process. In this study, we developed and characterized an ultrathin (<10 µm) and solvent-resistant thin-film composite (TFC) membrane for use in the OSFO process. The commercialized polyethylene (PE) membrane with thicknesses of 5 and 9 μm were selected as a novel substrate, and hydrophilic polyvinyl alcohol was introduced on its surface to enhance hydrophilicity and structural attributes. After interfacial polymerization reaction, the utilization of the 5 μm PE substrate elevates water and alcohol fluxes, while the 9 μm PE substrate possesses the higher rejection for salts and APIs. Notably, following a 2-hour DMF activation process, the resulting TFC 5 -0.05 membrane attains a noteworthy ethanol flux of 2.6 L m–2h−1, along with a robust oxytetracycline rejection of > 95 % during 10-hour continuous operation. These findings underscore the favorable permselectivity of the ethanol and oxytetracycline and solvent stability of the ultrathin PE-PA TFC membrane on the commercial substrates for OSFO process. [ABSTRACT FROM AUTHOR]