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[Display omitted] • PEI-grafted UiO-66-NH 2 (UiO-66-PEI) was intercalated into GO. • Incorporation of UiO-66-PEI tailored the surface properties and interlayer channels of the GO membrane. • The UiO-66-PEI enhanced the IPA-water separation efficiency of nanocomposite membrane. The separation of isopropanol (IPA)-water mixtures is a critical process in chemical, bioprocess, and electronics industries. This study aims to develop a high-performance pervaporation (PV) membrane for IPA-water separation through incorporating UiO-66-PEI into graphene oxide (GO) membrane by leveraging the combined properties of 2D and 3D nanomaterials. Polyethyleneimine (PEI) was grafted into UiO-66-NH 2 to synthesize UiO-66-PEI using Schiff base reactions with glutaraldehyde. The UiO-66-PEI was subsequently intercalated into GO layers to fabricate the membrane in hydrolyzed polyacrylonitrile support using pressure filtration. This intercalation significantly impacted the chemical properties and structure of the GO, leading to an enhanced PV performance in IPA-water mixture separation. The resulting membrane demonstrated a remarkable separation efficiency with a permeation flux of 1479 g∙m−2∙h−1 and a high water content in the permeate of 99.60 wt%. Notably, the exceptional separation performance of the nanocomposite membranes was sustained across varying feed concentrations, operating temperatures, and during long-term operational periods. The findings in this work offer valuable insights into the fabrication of GO-based heterostructure membranes with significant implications for advancing PV separation technology. [ABSTRACT FROM AUTHOR]

The right choice of porous support and diamine monomer is crucial in fabricating TFC membranes with improved performance. In this study, the effect of the supporting layer and diamine monomer structure in preparing TFC membranes for dye/salt separation was investigated. Supports used are polysulfone (PSf), polyacrylonitrile (PAN), and hydrolyzed PAN (mPAN) while diamine monomers used are piperazine (PIP), 1,3-diaminopropane (DAPE), and 1,4-bis(3-aminopropyl) piperazine (BAPP). Changing the porous substrate and monomer not only affects membrane physical and chemical morphology but also the performance of TFC NF membranes. Characterization and NF tests revealed that the TFC membrane prepared using mPAN as support and PIP as diamine monomer had most hydrophilic, roughest surface, and lowest crosslinking degree, and it delivered the optimum NF performance: J = 127.66 ± 12.61 LMH; RBrilliant Blue = 99.28 ± 0.57% RCongo Red = 99.21 ± 0.08%; RNaCl = 14.00 ± 6.16%. [ABSTRACT FROM AUTHOR]

This study introduces an innovative thin-film composite (TFC) nanofiltration membrane made from sulfonated polyvinyl alcohol (SPVA)-based polyester, specifically engineered for effective wastewater treatment. This novel membrane is developed through interfacial polymerization on a polysulfone substrate, demonstrating exceptional water permeability and filtration efficiency. It is particularly effective in separating dyes and salts due to its superior hydrophilicity, optimized surface charge, and precisely tailored morphology. Critical fabrication parameters were finely tuned, utilizing a 2 wt% SPVA solution and a 0.35 wt% trimesoyl chloride (TMC) in the organic phase, with both immersion and polymerization times set at 2 min. The performance metrics are outstanding, featuring a water permeance of 97 L m−2 h−1·bar−1, high dye rejection rates (99.51 % for Congo Red and 99.55 % for Brilliant Blue), and significant salt permeability (30.35 % for Na 2 SO 4 and 29.93 % for MgSO 4). The membrane also exhibits excellent antifouling properties, robust chlorine resistance (up to 48,000 ppm h), and sustained operational stability, underscoring its industrial viability for dye and textile effluent treatment. The TFC-SPVA membrane addresses critical environmental challenges in wastewater management, marking a significant advancement in membrane technology. [Display omitted] • Developed SPVA-based TFC membrane for wastewater treatment. • Achieved high dye rejection (99.51 % for Congo Red). • Demonstrated exceptional chlorine resistance (up to 48000 ppm h). • Maintained high water permeance (95.09 L m−2 h−1·bar−1). • Showed robust antifouling properties and stability. [ABSTRACT FROM AUTHOR]

In recent years, transition metal dichalcogenides (TMDs) have garnered much significant attention for their potential in fabricating high-performance membranes and applications in water treatment. In the present study, molybdenum disulfide (MoS 2) nanosheets were modified using organic thiols to synthesize amino, hydroxyl, and carboxyl-functionalized MoS 2. These modified nanosheets were subsequently integrated into polyamide matrix to develop thin-film nanocomposite (TFN) membranes for dehydration of isopropanol-water mixtures through pervaporation. A comprehensive examination of the impact of incorporating functionalized MoS 2 on the physical and chemical properties and separation performance of the resulting TFN membranes was carried out. Embedding MoS 2 created a bumpy structure with protuberances on the membrane surface. Amine groups from the modified MoS 2 played a crucial role in crosslinking with trimesoyl chloride during interfacial polymerization, contributing to an enhanced crosslinking degree in the membrane. Compared with the pristine membrane, hydroxyl and carboxyl-modified MoS 2 , the TFN membrane incorporated with amine-modified MoS 2 exhibited the highest separation performance with total flux of 1438 g m−2 h−1 and water content in permeate of 99.37 wt% for separating 70 wt% isopropanol aqueous solution. Remarkably, the TFN membrane exhibited a robust performance under high operating temperatures and high feed water concentrations, demonstrating its resilience in challenging conditions. Furthermore, the membrane exhibited stable long-term operational performance, highlighting its potential for pervaporation dehydration applications in the industry. The insights gained from this study contribute to the ongoing development of advanced membrane technologies based on TMDs. [Display omitted] • MoS 2 was facilely conjugated using different organic thiols. • Functionalized MoS 2 modulated the cross-linking degree and thickness of separation layer. • Amine functionalized MoS 2 enhanced the separation efficiency the most. • Modified membrane exhibited a robust performance at different operating conditions. [ABSTRACT FROM AUTHOR]

• Sodium- or organo-montmorillonite (O-MMT) was embedded into alginate membrane. • Incorporating O-MMT improved the membrane property and separation efficiency. • The hybrid membrane had stable performance at wide operating condition. In this work, two different montmorillonite (MMT) nanoclays were incorporated in sodium alginate (Alg) solution for fabrication of hybrid membrane for pervaporative separation of aqueous isopropanol solution. Sodium-MMT (Na-MMT) was modified to organo-montmorillonite (O-MMT) using cationic surfactant dialkyldimethyl ammonium chloride (DDAC). The influence of incorporating MMTs on the membrane properties and separation performance was investigated. Intercalating of DDA+ on Na-MMT tailored the chemical structure and morphology of the MMTs. Integrating of MMTs modified the physicochemical properties of the membranes. The membrane morphology shows the homogeneous dispersion of MMTs in athe Alg matrix. Positron annihilation lifetime spectroscopy analysis revealed a tuned microstructure of the membranes. Swelling measurements showed better compatibility of O-MMT than the Na-MMT with the Alg matrix. As a result, Alg O-MMT had better separation performance than the Alg Na-MMT with permeation flux of 4764 g∙m−2∙h−1 and water concentration in permeate of 99.99 wt% on dehydrating 70 wt% IPA/water aqueous solution at 25 °C. Owing to the favorable compatibility between the polymer and filler, Alg O-MMT membrane demonstrated stability at different pervaporation operating conditions and long-term use. Our results demonstrated that the properties and separation performance of Alg membrane can be enhanced through incorporation of O-MMTs. [ABSTRACT FROM AUTHOR]

Zwitterionic copolymers, poly(glycidyl methacrylate-sulfobetaine methacrylate) [poly(GMA-SBMA)], was incorporated into graphene oxide (GO) to form a GO–poly(GMA-SBMA) framework. This compound was then deposited onto a polysulfone support through pressure-assisted filtration to fabricate hybrid membranes. Optimum fabrication conditions were determined by varying the poly(GMA-SBMA) loading. Attenuated total reflectance-Fourier transform infrared and X-ray photoelectron spectroscopy confirmed the covalent bonding between poly(GMA-SBMA) and GO. On account of loading incremental amounts of poly(GMA-SBMA), the membrane thickness was increased (illustrated by field emission scanning electron microscopic images), the interlayer spacing between GO sheets was expanded (shown by X-ray diffraction patterns), and the membrane hydrophilic properties were enhanced (indicated by water contact angle data). Relative to the pristine GO membrane, hybrid membranes fabricated at optimum conditions exhibited superior separation performance (99.60 wt% water concentration in permeate and 1102 g m−2⋅h−1 permeation flux) on dehydrating a 70 wt% aqueous isopropanol solution by pervaporation. This present study explored the potential of poly(GMA-SBMA) for developing hybrid membranes with excellent pervaporation performance. Image 1 • Graphene oxide is functionalized with zwitterionic copolymers having epoxy groups. • Zwitterionic copolymers alter the interlayer d-spacing of graphene oxide. • Hybrid membranes exhibit superior separation of water from isopropanol. [ABSTRACT FROM AUTHOR]

In this study, polyacrylic acid (PAA) and poly (diallyldimethylammonium chloride) (PDDA) were self-assembly on the surface of hydrolyzed polyacrylonitrile membrane. Graphene oxide (GO) was embedded on the membrane through dispersing it on either PAA or PDDA solution. The presence of GO in the composite membrane made the surface morphology become rougher than that of the pristine membrane. In addition, the membrane maintained hydrophilic with improved surface electronegativity. During the performance evaluation (1 M Na 2 SO 4 as draw solution, and pure water as feed), the membrane prepared with GO in PAA solution had the highest separation efficiency. Because GO facilitates the strong electrostatic interaction between PAA + GO with PDDA, resulting in a dense selective layer. At optimum concentration of GO in PAA with a bilayer, the composite membrane exhibited a water permeation flux of 16 LMH and a salt reverse diffusion of 22.3 gMH. Using different types of salts (Na 2 SO 4 , NaCl, MgSO 4 , MgCl as draw solution), the composite membrane confirmed that it was a nanofiltration-forward osmosis like type of membrane, giving a high separation efficiency for a draw solution of Na 2 SO 4. • GO was incorporated in polyelectrolyte membrane. • Dispersing the GO in PAA is better than dispersing in PDDA. • Incorporating GO improved the membrane performance in FO. [ABSTRACT FROM AUTHOR]