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Graphene oxide (GO)-based membranes have exhibited fascinating superiority in water treatment. However, water transfer resistance caused by the tortuous interlayer pathway and swelling in aqueous solutions of GO membranes are still bottlenecks in wastewater treatment. Here, a heterostructured GO membrane was designed by intercalating amino-terminated MXene (MXene-NH2) in GO layers. Specifically, the inserted MXene-NH2 with a small size in the gap of GO layers can increase the vertical distance between GO layers and offer a shortened water transport pathway for enhanced permeability. Meanwhile, the interaction between the amino groups of MXene-NH2 and the carboxyl groups of GO can restrict the deformation of the layered structure, thus inducing improved stability. Accordingly, the obtained GO/MXene-NH2 composite membrane exhibited a flux of about 11.31 L/(m2 h bar) at low pressure (1 bar), which was 4 times higher than that of the GO membrane (̃2.73 L/(m2 h bar)). Meanwhile, high rejections of the membrane for different charged dyes (≥96%) remained. Besides, the GO/MXene-NH2 membrane showed excellent antiswelling properties. This strategy provides a method for the design of a heterostructure membrane and promotes the practical application of the GO membrane. [ABSTRACT FROM AUTHOR]

The structure characteristic of polyvinylidene fluoride membrane and graphene oxide was main introduced, respectively, and the advantages of organic-inorganic hybrid membrane were analyzed. The preparation method of GO/PVDF membrane were stated in detail, including solution casting method, electrospinning method, chemical grafting method, vacuum filtration method and so on. Based on the recent research status, the advantages and disadvantages of the above methods were analyzed. Then, the effects of GO on pore size, hydrophilicity and hydrophobicity, membrane flux, rejection, and mechanical properties of membrane were expounded. And the applications of GO/PVDF membrane in water treatment and other potential applications were reviewed. It was found that the solution casting method was simple and short, and the membrane produced by the chemical grafting method had a stable bond between each component and a long service time, while the membrane produced by the electrostatic spinning method had a large specific surface area and high porosity. The capillary action of the GO lamellar capillarity occurred, and the smaller particles would pass through the GO lamellar at a faster speed, the membrane flux was improved in macroscopic view. GO also improved surface finish, reduced the impurities blockage and pollution, and then improving service life of GO/PVDF membrane. The research direction and development trend of GO/PVDF membrane was prospected, thus would provide theoretical basis and technical support for the construction of efficient and stable PVDF separation membrane. [ABSTRACT FROM AUTHOR]

The treatment of tritiated nuclear wastewater is facing greater challenges with the continuous expansion of the nuclear industry. The key to solving the issue of detritium in low-abundance tritium water lies in developing highly efficient and cost-effective hydrogen isotope separation technology. Graphene oxide (GO) membrane separation method exhibits greater potential compared to other existing energy-intensive technologies for the challenging task of hydrogen isotope separation in nuclear wastewater. In recent years, researchers have explored few strategies to enhance the performance of graphene oxide (GO) membranes in hydrogen isotope water treatment, recognizing the current limitations in separation efficiency. In this study, the GO/g-C3N4 composite membrane has been successfully employed for the first time in the separation of hydrogen isotopes in water. A series of GO membranes were prepared and their performances were tested by a self-made experimental device. As a result, the separation performance of the GO membrane was enhanced by the modification with graphitic carbon nitride (g-C3N4). The permeation rate of the GO/g-C3N4 membrane was higher than that of the GO membrane, while maintaining a high separation factor. Our study also demonstrated that this phenomenon can be attributed to the changes in membrane structure at the microscopic scale. The H/D separation factor and the permeate flux of the composite membrane containing g-C3N4 of 6.7% by mass were 1.10 and 7.2 × 10−5 g·min−1·cm−2 are both higher than that of the GO membrane under the same experimental conditions, which is promising for the isotope treatment. [ABSTRACT FROM AUTHOR]

Objective. The purpose of the study is to determine the prospects for using a membrane refrigeration unit for the production of cold as an alternative to absorption. Method. The study was carried out using a numerical experiment and verification of the results obtained on an experimental bench. Result. An analysis was made of the use of a traditional absorption refrigeration machine and a membrane refrigeration machine from the point of view of energy efficiency and the number of working elements. Presented for comparison are methods for calculating the separation process of the “absorbent-refrigerant” mixture based on reverse osmosis processes and a water-ammonia absorption refrigeration unit. Conclusion. The use of separation processes in membrane apparatuses for the production of cold in mixed refrigeration machines, as an alternative to absorption refrigeration machines, will ensure a more stable process for obtaining refrigerant from the mixture, reduce material costs for the production of a refrigeration unit and increase the energy efficiency of a refrigeration unit operating on mixed components.

Temperature-responsive separation membranes can significantly change their permeability and separation properties in response to changes in their surrounding temperature, improving efficiency and reducing membrane costs. This study focuses on the modification of polyvinylidene fluoride (PVDF) membranes with amphiphilic temperature-responsive copolymer and inorganic nanoparticles. We prepared an amphiphilic temperature-responsive copolymer in which the hydrophilic poly(N-isopropyl acrylamide) (PNIPAAm) was side-linked to a hydrophobic polyvinylidene fluoride (PVDF) skeleton. Subsequently, PVDF-g-PNIPAAm polymer and graphene oxide (GO) were blended with PVDF to prepare temperature-responsive separation membranes. The results showed that temperature-responsive polymers with different NIPAAm grafting ratios were successfully prepared by adjusting the material ratio of NIPAAm to PVDF. PVDF-g-PNIPAAm was blended with PVDF with different grafting ratios to obtain separate membranes with different temperature responses. GO and PVDF-g-PNIPAAm formed a relatively stable hydrogen bond network, which improved the internal structure and antifouling performance of the membrane without affecting the temperature response, thus extending the service life of the membrane. [ABSTRACT FROM AUTHOR]

An electrochemical floatation system (EFS)-based sewage-treatment process that applied a dimensionally stable anode (DSA) was developed to secure treated sewage water from sewage-treatment plants for reuse. The DSA was fabricated at a temperature of 673–923 K by dispersing a low quantity of activated carbon on a titanium plate coated with mixed metal oxides (Pt, Re, Pd, Re, and Ir) to a thickness of 5 μm. The average size of the bubbles generated through the DSA of the EFS was 20–40 μm, thus confirming microbubble generation. An efficiency assessment of a titanium-based DSA confirmed metal oxide activity through the removal of Escherichia coli (100%) and total organic carbon (TOC; 48.83%) at a reaction time shorter than 10 min and a low current density (19.6 A/m2). During the long-term operation of the EFS with the separation membrane process, the average removal efficiency was 94.7%, 90.0%, 96.1%, 90.9%, and 98.0% for suspended solids, biochemical oxygen demand, TOC, total nitrogen, and total phosphorous, respectively. Coliforms were not detected. Overall, our EFS coupled with the separation membrane process produced high-quality recycled water that could be used for various purposes according to the water-quality standards for different applications. [ABSTRACT FROM AUTHOR]

The treatment of tritiated nuclear wastewater is facing greater challenges with the continuous expansion of the nuclear industry. The key to solving the issue of detritium in low-abundance tritium water lies in developing highly efficient and cost-effective hydrogen isotope separation technology. Graphene oxide (GO) membrane separation method exhibits greater potential compared to other existing energy-intensive technologies for the challenging task of hydrogen isotope separation in nuclear wastewater. In recent years, researchers have explored few strategies to enhance the performance of graphene oxide (GO) membranes in hydrogen isotope water treatment, recognizing the current limitations in separation efficiency. In this study, the GO/g-C3N4 composite membrane has been successfully employed for the first time in the separation of hydrogen isotopes in water. A series of GO membranes were prepared and their performances were tested by a self-made experimental device. As a result, the separation performance of the GO membrane was enhanced by the modification with graphitic carbon nitride (g-C3N4). The permeation rate of the GO/g-C3N4 membrane was higher than that of the GO membrane, while maintaining a high separation factor. Our study also demonstrated that this phenomenon can be attributed to the changes in membrane structure at the microscopic scale. The H/D separation factor and the permeate flux of the composite membrane containing g-C3N4 of 6.7% by mass were 1.10 and 7.2 × 10−5 g·min−1·cm−2 are both higher than that of the GO membrane under the same experimental conditions, which is promising for the isotope treatment.

Studies on self-healing capsules embedded in cement composites to heal such cracks have recently been actively researched in order to improve the dimensional stability of concrete structures. In particular, capsule studies were mainly conducted to separately inject reactive healing solutions into different capsules. However, with this method, there is an important limitation in that the probability of self-healing is greatly reduced because the two healing solutions must meet and react. Therefore, we propose three-dimensional (3D) printer-based self-healing capsules with a membrane structure that allows two healing solutions to be injected into one capsule. Among many 3D printing methods, we used the fusion deposition modeling (FDM) to design, analyze, and produce new self-healing capsules, which are widely used due to their low cost, precise manufacturing, and high-speed. However, polylactic lactic acid (PLA) extruded in the FDM has low adhesion energy between stacked layers, which causes different fracture strengths depending on the direction of the applied load and the subsequent performance degradation of the capsule. Therefore, the isotropic fracture characteristics of the newly proposed four types of separated membrane capsules were analyzed using finite element method analysis. Additionally, capsules were produced using the FDM method, and the compression test was conducted by applying force in the x, y, and z directions. The isotropic fracture strength was also analyzed using the relative standard deviation (RSD) parameter. As a result, the proposed separated membrane capsule showed that the RSD of isotropic fracture strength over all directions fell to about 18% compared to other capsules. [ABSTRACT FROM AUTHOR]

Temperature-responsive separation membranes can significantly change their permeability and separation properties in response to changes in their surrounding temperature, improving efficiency and reducing membrane costs. This study focuses on the modification of polyvinylidene fluoride (PVDF) membranes with amphiphilic temperature-responsive copolymer and inorganic nanoparticles. We prepared an amphiphilic temperature-responsive copolymer in which the hydrophilic poly(N-isopropyl acrylamide) (PNIPAAm) was side-linked to a hydrophobic polyvinylidene fluoride (PVDF) skeleton. Subsequently, PVDF-g-PNIPAAm polymer and graphene oxide (GO) were blended with PVDF to prepare temperature-responsive separation membranes. The results showed that temperature-responsive polymers with different NIPAAm grafting ratios were successfully prepared by adjusting the material ratio of NIPAAm to PVDF. PVDF-g-PNIPAAm was blended with PVDF with different grafting ratios to obtain separate membranes with different temperature responses. GO and PVDF-g-PNIPAAm formed a relatively stable hydrogen bond network, which improved the internal structure and antifouling performance of the membrane without affecting the temperature response, thus extending the service life of the membrane.

An electrochemical floatation system (EFS)-based sewage-treatment process that applied a dimensionally stable anode (DSA) was developed to secure treated sewage water from sewage-treatment plants for reuse. The DSA was fabricated at a temperature of 673–923 K by dispersing a low quantity of activated carbon on a titanium plate coated with mixed metal oxides (Pt, Re, Pd, Re, and Ir) to a thickness of 5 μm. The average size of the bubbles generated through the DSA of the EFS was 20–40 μm, thus confirming microbubble generation. An efficiency assessment of a titanium-based DSA confirmed metal oxide activity through the removal of Escherichia coli (100%) and total organic carbon (TOC; 48.83%) at a reaction time shorter than 10 min and a low current density (19.6 A/m2). During the long-term operation of the EFS with the separation membrane process, the average removal efficiency was 94.7%, 90.0%, 96.1%, 90.9%, and 98.0% for suspended solids, biochemical oxygen demand, TOC, total nitrogen, and total phosphorous, respectively. Coliforms were not detected. Overall, our EFS coupled with the separation membrane process produced high-quality recycled water that could be used for various purposes according to the water-quality standards for different applications.

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Polyacrylamide (PAAm)-silica organic-inorganic hybrid membranes for carbon dioxide (CO2) separation were prepared via in-situ polymerization. Formation of silica and PAAm via sol-gel method and in-situ polymerization was confirmed by IR spectroscopy. Single gas permeances through the membranes were measured at 298, 373 and 423 K using CO2, He and N2. The ideal separation factor (the ratio of the permeances) of CO2/N2 through the AAm10 membrane (starting solution composition; tetraethoxysilane: methyltriethoxysilane: distilled water: hydrochloric acid: ethanol: acrylamide: dimethyl 2,2′-azobis(isobutyrate) = 0.4: 0.6: 2: 0.01: 20: 1.0: 0.1 in molar ratio) was 25.4 at 298 K. This value was thirty times higher than the theoretical Knudsen value (CO2/N2 = 0.8). Binary gas permeation at 298 K was also investigated using a gas mixture of 50%CO2–50%N2. The ideal separation factor (the ratio of the permeances) of CO2/N2 through the membrane was 24.9. This value was the same as the ideal separation factor of CO2/N2 calculated from the single gas measurement. Such a high CO2 selectivity in 50%CO2-50%N2 feed gas was also found even at high temperature for this membrane. Highlights: Polyacrylamide-silica organic-inorganic hybrid membranes for carbon dioxide (CO2) separation were prepared via in-situ polymerization. The effects of acrylamide (AAm) content on the gas permeances of CO2, He, N2 through the membranes were investigated. AAm10 membrane (starting solution composition; tetraethoxysilane: methyltriethoxysilane: distilled water: hydrochloric acid: ethanol: acrylamide: dimethyl 2,2′-azobis(isobutyrate) = 0.4:0.6:2:0.01:20:1.0:0.1 in molar ratio) exhibits the highest CO2 selectivity, the ideal separation factor (the ratio of the permeances) of CO2/N2 was 25.4 at 298 K. AAm10 membrane exhibited high CO2 selectivity at 298 K for 50%CO2-50%N2 feed gas mixture, where the ideal separation factor (the ratio of the permeances) of CO2/N2 was 24.9. [ABSTRACT FROM AUTHOR]

This review explores the applicability of graphene oxide (GO) membranes in vapor permeation, emphasizing their unique properties and promising capabilities. In the context of eco-friendly separation processes, such as pervaporation (PV) and vapor permeation (VP), GO membranes can selectively permeate water vapor to separate vapor mixtures. Their distinct structure, featuring slip flow and precise water molecule alignment in angstrom-scale interlayer spaces, facilitates fast water transport. This review proposes the selective adsorption–pore flow–evaporation model as a plausible mechanism for vapor permeation through GO membranes. Despite extensive research on GO membranes for PV in separating mixtures, their application in VP remains underexplored. Nevertheless, their selectivity for water vapor and effectiveness in gas dehumidification processes emphasize their applicability for chemical dehydration (purification). Future research in this field can advance membrane technologies, offering more sustainable and efficient separation processes across various industries for purifying and recycling chemicals and separating azeotropic mixtures. [Display omitted] [ABSTRACT FROM AUTHOR]

Semiconducting membrane combined with nanomaterials is an auspicious combination that may successfully eliminate diverse waste products from water while consuming little energy and reducing pollution. Creating an inexpensive, steady, flexible, and diversified business material for membrane production is a critical challenge in membrane technology development. Because of its unusual structure and high catalytic activity, graphitic carbon nitride (g-C3N4) has come out as a viable material for membranes. Furthermore, their great durability, high permanency under challenging environments, and long-term use without decrease in flux are significant advantages. The advanced material techniques used to manage the molecular assembly of g-C3N4 for separation membrane were detailed in this review work. The progress in using g-C3N4-based membranes for water treatment has been detailed in this presentation. The review delivers an updated description of g-C3N4 based membranes and their separation functions and new ideas for future enhancements/adjustments to address their weaknesses in real-world situations. Finally, the ongoing problems and promising future research directions for g-C3N4-based membranes are discussed.

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The current improvement in science and engineering, actively dealing with surfaces and interfaces, turns into a functioning control with a thriving advancement propensity. Superlyophobic/superlyophilic phenomena in surface sciences have pulled in broad considerations of researchers and specialists. Inspired by the natural and living organism, researchers have designed different biomimetic materials with exceptional surface wettability, such as the smart wetting of asymmetric spider silk surfaces. These smart materials with superlyophobic/superlyophilic wettability are generally utilized for water assortment, self-cleaning, fluid transportation and separation, and many researchers' domains. Among them, emulsion separation, including division of oil-water blend, mixtures of immiscible liquids and oil-water emulsions, is highlighted by an increasing number of researchers. Numerous materials with one- and two-dimensional morphology, smart surfaces, and super wettability have been effectively designed and utilized in various scientific research applications. We expect that these bioinspired materials with super wettability can have promising applications in practical for emulsion destabilization and liquid transportation. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) membranes have gained significant attention as a promising material for separation by selective permeation processes due to their advantageous structural and chemical properties, including high water permeability, chemical resistance, and mechanical strength. In this study, we explore the potential applications of GO membranes in pervaporation to separate liquid mixtures. The layered structure and hydrophilic nature of GO membrane facilitate rapid and selective water transport through angstrom-scale interlayer spacings, resulting in superior performance over conventional polymeric and inorganic membranes. The unique mass transport mechanisms - slip flow and molecular alignment - enable GO membranes to selectively permeate water over organic solvents. For chemical dehydration, GO membranes are the most potential candidates. Furthermore, advancements in composite GO membranes and cross-linking techniques that improve their stability and separation performance are discussed. This study highlights the advantages of GO membranes and their potential to replace or complement existing technologies, by emphasizing their role in advancing membrane-based separation and promoting environmental sustainability. Future research is expected to optimize the fabrication techniques for GO membranes and expand their application scope., (© 2024 Wiley-VCH GmbH.)

Studies on self-healing capsules embedded in cement composites to heal such cracks have recently been actively researched in order to improve the dimensional stability of concrete structures. In particular, capsule studies were mainly conducted to separately inject reactive healing solutions into different capsules. However, with this method, there is an important limitation in that the probability of self-healing is greatly reduced because the two healing solutions must meet and react. Therefore, we propose three-dimensional (3D) printer-based self-healing capsules with a membrane structure that allows two healing solutions to be injected into one capsule. Among many 3D printing methods, we used the fusion deposition modeling (FDM) to design, analyze, and produce new self-healing capsules, which are widely used due to their low cost, precise manufacturing, and high-speed. However, polylactic lactic acid (PLA) extruded in the FDM has low adhesion energy between stacked layers, which causes different fracture strengths depending on the direction of the applied load and the subsequent performance degradation of the capsule. Therefore, the isotropic fracture characteristics of the newly proposed four types of separated membrane capsules were analyzed using finite element method analysis. Additionally, capsules were produced using the FDM method, and the compression test was conducted by applying force in the x, y, and z directions. The isotropic fracture strength was also analyzed using the relative standard deviation (RSD) parameter. As a result, the proposed separated membrane capsule showed that the RSD of isotropic fracture strength over all directions fell to about 18% compared to other capsules.

Separation membranes have a wide application in the food industry, for instance, in the clarification/fractionation of milk, the concentration/separation of selected components, and wastewater treatment. They provide a large area for bacteria to attach and colonize. When a product comes into contact with a membrane, it initiates bacterial attachment/colonization and eventually forms biofilms. Several cleaning and sanitation protocols are currently utilized in the industry; however, the heavy fouling of the membrane over a prolonged duration affects the overall cleaning efficiency. In view of this, alternative approaches are being developed. Therefore, the objective of this review is to describe the novel strategies for controlling membrane biofilms such as enzyme-based cleaner, naturally produced antimicrobials of microbial origin, and preventing biofilm development using quorum interruption. Additionally, it aims to report the constitutive microflora of the membrane and the development of the predominance of resistant strains over prolonged usage. The emergence of predominance could be associated with several factors, of which, the release of antimicrobial peptides by selective strains is a prominent factor. Therefore, naturally produced antimicrobials of microbial origin could thus provide a promising approach to control biofilms. Such an intervention strategy could be implemented by developing a bio-sanitizer exhibiting antimicrobial activity against resistant biofilms.

Membrane-based nanotechnology possesses high separation efficiency, low economic and energy consumption, continuous operation modes and environmental benefits, and has been utilized in various separation fields. Two-dimensional nanomaterials (2DNMs) with unique atomic thickness have rapidly emerged as ideal building blocks to develop high-performance separation membranes. By rationally tailoring and precisely controlling the nanochannels and/or nanoporous apertures of 2DNMs, 2DNM-based membranes are capable of exhibiting unprecedentedly high permeation and selectivity properties. In this review, the latest breakthroughs in using 2DNM-based membranes as nanosheets and laminar membranes are summarized, including their fabrication, structure design, transport behavior, separation mechanisms, and applications in liquid separations. Examples of advanced 2D material (graphene family, 2D TMDs, MXenes, metal–organic frameworks, and covalent organic framework nanosheets) membrane designs with remarkably perm-selective properties are highlighted. Additionally, the development of strategies used to functionalize membranes with 2DNMs are discussed. Finally, current technical challenges and emerging research directions of advancing 2DNM membranes for liquid separation are shared. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water-lean solvents are considered as a promising solution for carbon dioxide (CO2) capture. Candidate CO2 capture molecules include N-(2-ethoxyethyl)-3-morpholinopropan-1-amine (2-EEMPA), 3-methoxy-N-(pyridine-2-ylemthyl)propan-1-amine (MPMPA), and 1-((1,3-Dimethylimidazolidin-2-ylidene)amino)propan-2-ol (1-IPADM-2-BOL). When integrating the water-lean solvents with the separation membrane to form a hybrid system, it would have a higher driving force to pull CO2 through a membrane. In addition, including a membrane in the direct air capture (DAC) system would reduce the evaporation of capture solvents. Therefore, it is important to understand the chemical compatibility of the solvents with the separation membranes to better integrate them into the process for DAC of CO2. Characteristic peaks of water-lean solvents and separation membrane were observed in the static spectral measurements of time-of-flight secondary ion mass spectrometry (ToF-SIMS). For example, m/z+ 217.190 C11H25N2O2+, m/z+ 181.129 C10H17N2O+, and m/z+ 172.145 C8H18N3O+, are the protonated 2-EEMPA, protonated MPMPA, and protonated 1-IPADM-2-BOL, respectively. Similarly, the fragment of CO2 separation membrane, m/z+ 263.082 C16H11N2O2+, a synthesized PEEK-ionene, was observed, showing molecular detection of ToF-SIMS. In addition, x-ray photoelectron spectroscopy (XPS) was performed to quantitatively verify the change of carbon ratio at the interface, indicating the interactions between water-lean solvents and the separation membrane. These findings show that the interface between the CO2 separation membrane and water-lean solvents should be studied at the molecular level, because they provide insights into how we could design hybrid systems comprised of CO2 separation membranes and capture solvents.

Thin-film composite (TFC) polyamide (PA) membrane has been widely applied in nanofiltration, reverse osmosis, and forward osmosis, including a PA rejection layer by interfacial polymerization on a porous support layer. However, the separation performance of TFC membrane is constrained by the trade-off relationship between permeability and selectivity. Although thin-film nanocomposite (TFN) membrane can enhance the permeability, due to the existence of functionalized nanoparticles in the PA rejection layer, the introduction of nanoparticles leads to the problems of the poor interface compatibility and the nanoparticles agglomeration. These issues often lead to the defect of PA rejection layers and reduction in selectivity. In this review, we summarize a new class of structures of TFN membranes with functionalized interlayers (TFNi), which promises to overcome the problems associated with TFN membranes. Recently, functionalized two-dimensional (2D) nanomaterials have received more attention in the assembly materials of membranes. The reported TFNi membranes with 2D interlayers exhibit the remarkable enhancement on the permeability, due to the shorter transport path by the “gutter mechanism” of 2D interlayers. Meanwhile, the functionalized 2D interlayers can affect the diffusion of two-phase monomers during the interfacial polymerization, resulting in the defect-free and highly crosslinked PA rejection layer. Thus, the 2D interlayers enabled TFNi membranes to potentially overcome the longstanding trade-off between membrane permeability and selectivity. This paper provides a critical review on the emerging 2D nanomaterials as the functionalized interlayers of TFNi membranes. The characteristics, function, modification, and advantages of these 2D interlayers are summarized. Several perspectives are provided in terms of the critical challenges for 2D interlayers, managing the trade-off between permeability, selectivity, and cost. The future research directions of TFNi membranes with 2D interlayers are proposed.

This study investigates the preparation of polyetherimide (PEI) – LaNi 5 composites films for hydrogen storage. Prior to the polymer addition, LaNi 5 was ball-milled at different conditions (250, 350, and 450 RPM) and annealed at 500 °C for 1 h under vacuum. The composites were produced with BM-LaNi 5 -350 (PEI/LaNi 5 -350) and annealed BM-LaNi 5 -350 (PEI/LaNi 5 -350-TT). Membranes were successfully produced through solvent casting assisted by an ultrasonic bath. The particles dispersion and the film morphology did not change after hydrogenation cycles. In the H 2 sorption experiments at 43 °C and 20 bar, the films stored H 2 without incubation time; both samples reached a capacity of ~0.6 wt%. The H 2 sorption kinetics of PEI/LaNi 5 -350 was comparable to that of BM-LaNi 5 -350, whereas PEI/LaNi 5 -350-TT presented significantly slower kinetics. LaNi 5 oxidation was hindered by PEI, showing that it can be explored to improve metal hydrides air resistance. The results demonstrated that PEI films filled with LaNi 5 are promising materials for hydrogen storage. [Display omitted] • PEI/LaNi 5 composite films are mechanically resistant and flexible. • The composites stored up to 0.6 wt% of H 2 at 43 °C and 20 bar. • PEI immobilized LaNi 5 particles during the hydrogen sorption/desorption cycles. • The polymer hindered LaNi 5 oxidation upon exposure to ambient air. [ABSTRACT FROM AUTHOR]

[Display omitted] Hydrophobic micro-porous membrane such as polyvinylidene fluoride (PVDF) with excellent thermal-/chemical-stability and low surface energy has received extensive attention in industrial water treatment and sustainable energy conversion. However, undesirable contaminants caused by inevitable proteins or microorganisms adhesion may lead to a rapid loss of separation efficiency, which significantly deteriorate their porous structures and eventually limit their practical performance. Herein, we present a scalable approach for fabricating comb-like copolymer modified PVDF membranes (PVDF-PN@AgNPs) that prevent bacteria from proliferating on the surface and temperature-controlled release of adhered contaminants. Comb-like structured copolymers were imparted to a polydopamine (PDA)-treated PVDF membrane by Michael addition reaction, which enabled a covalent binding of comb-like structured copolymers to the membrane. Such unique structural design of grafted copolymer, containing hydrophilic side chain and temperature-responsive chain backbone, stably prevents bacteria adhesion and provides reversible surface wettability. Therefore, the resultant membranes were evaluated to prevent bacterial adhesion, high touch-killing efficiency and temperature-controlled contaminants release (~99% of protein and ~75% of bacteria). Moreover, with the collapse and stretch of grafted copolymer chain backbone, the synthetic membrane further reversibly adjusted inner micro-porous structure and surface wettability, which eventually helped to achieve variable water fluid transport efficiency. This study not only provides a feasible structural design for stably coping with the challenging of antifouling and subsequent contamination adhesion of PVDF membrane, but also potentially answers the significant gap between lab research advances and practical application, particularly in the industrial membrane field. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Membrane-based nanotechnology possesses high separation efficiency, low economic and energy consumption, continuous operation modes and environmental benefits, and has been utilized in various separation fields. Two-dimensional nanomaterials (2DNMs) with unique atomic thickness have rapidly emerged as ideal building blocks to develop high-performance separation membranes. By rationally tailoring and precisely controlling the nanochannels and/or nanoporous apertures of 2DNMs, 2DNM-based membranes are capable of exhibiting unprecedentedly high permeation and selectivity properties. In this review, the latest breakthroughs in using 2DNM-based membranes as nanosheets and laminar membranes are summarized, including their fabrication, structure design, transport behavior, separation mechanisms, and applications in liquid separations. Examples of advanced 2D material (graphene family, 2D TMDs, MXenes, metal–organic frameworks, and covalent organic framework nanosheets) membrane designs with remarkably perm-selective properties are highlighted. Additionally, the development of strategies used to functionalize membranes with 2DNMs are discussed. Finally, current technical challenges and emerging research directions of advancing 2DNM membranes for liquid separation are shared.

Microvolume blood collection technologies are of intense interest in healthcare. Whereas dried blood spots collect all the blood components, the majority of clinical tests are performed on the noncellular, plasma component of blood. Thus, there is a critical need for a robust plasma‐collecting device, which can stabilize biomarkers of interest for clinical analysis. A dried plasma spot, which consists of a separation membrane for removing red blood cells (RBC) while avoiding cell lysis and an absorbing layer for collecting and stabilizing plasma biomarkers after separation may provide such a solution. We report a novel use of electrospun polyacrylonitrile membranes to achieve a very promising separation of RBCs with near‐zero retention of human albumin protein (MW: 66.5 kDa). Physicochemical qualities of the separation membranes can be further optimized through doping and refinement of electrospinning conditions. The membranes may have future potential in microvolume sample collecting applications. [ABSTRACT FROM AUTHOR]

Based on experimental studies, the possibility and efficiency of usage of montmorillonite, saponite, and clinoptilolite as separation membranes during electroosmotic fractionation of hydrogen isotopes in an aqueous electrolyte solution was evaluated. For the experiments, the following samples were used: bentonite (Cherkasy deposit) with a content of montmorillonite of 75% (hereinafter referred to as montmorillonite), saponite (Varvariv deposit) and clinoptilolite (Sokyrnytsya deposit). It was found that under the influence of an electric field, electroosmotic filtration of the tritiated electrolyte occurs through weakly permeable membranes. Depending on the structural features of the mineral substance, various proton conductivity of the membranes was recorded, which determines the different intensity of the redistribution of ions of dissociated HTO molecules between the anode and cathode chambers. The largest difference between the specific activity of tritium in the anolyte and catholyte was obtained in the system where the mineral membrane was made of saponite (11% and 26% of the specific activity of tritium in the initial HTO, respectively). The least was the stability of the montmorillonite membrane. Its destruction upon interaction with a Na2CO3 solution led to electrolyte leakage and a decrease in the extraction of tritium from the filtrate (catholyte). The use of clinoptilolite when creating a composite with montmorillonite made it possible to increase the stability of the membrane and additional possibilities for fractionating hydrogen isotopes in an electrolyte. Electroosmotic filtration of the electrolyte was accompanied by fractionation of hydrogen isotopes in the mineral membranes of the experimental systems. The largest isotope effect was obtained in montmorillonite and composite montmorillonite-zeolite membranes, where the fractionation coefficient α in the fraction extracted from the interlayer space was 1.16 and 1.12, respectively. In a composite membrane, where the amount of clinoptilolite was 67.5%, isotopic hydrogen fractionation was also observed in the surface-adsorbed fraction (α = 1.5) and in a structurally bound form (α = 1.1). The use of saponite as an electroosmotic membrane leads to a smaller isotope effect than in a montmorillonite membrane, and is manifested in surface-adsorbed water (α = 1.08) and in the interlayer space (α = 1.02). The addition of quartz sand to montmorillonite reduces the efficiency of fractionation of hydrogen isotopes detected only in the surface-adsorbed fraction (α = 1.02). [ABSTRACT FROM AUTHOR]

Zwitterionic polymers are those that have both cationic and anionic charged moieties on the same side chain maintaining overall charge neutrality. Due to their ultra-hydrophilicity via electrostatically induced hydration and excellent biocompatibility, zwitterionic polymers have been extensively used in biomedical research. In this review, we first give a brief introduction to the physico-chemical properties, classification and synthesis of zwitterionic polymers. Specifically, we summarize the recent advances of zwitterionic polymers in the following fields. (1) Antifouling coatings: Unlike traditional antifouling polymers, zwitterionic polymers generate a tightly bound and structured water layer around the zwitterionic head groups which offer better antifouling properties in complex environments. Moreover, the surface modification strategies are also discussed. (2) Modification of proteins: Zwitterionic polymers have been applied to the modification of various kinds of proteins to increase the solubility and stability, inhibit the aggregation, enhance pharmacokinetics, reduce immunogenicity and mitigate the bioactivity loss of proteins. (3) Drug delivery system: Due to their excellent hydrophilicity, biocompatibility and nonfouling properties, zwitterionic polymers have been used to increase the solubility and stability of drug carrier, extend the circulation time, and enhance the cellular internalization. (4) Membrane separation system: The fabrication and function of zwitterionic polymers in separation membrane are briefly discussed. Finally, we conclude with a perspective for the development of zwitterionic polymers in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • The water-dispersed polydopamine modified porous organic polymer nanoparticle (PDA@POP) was synthesized. • The PDA@POP based nanochannel membrane was prepared via dip coating and interfacial crosslinking method. • The PDA@POPM membrane exhibits both high water permeability and dye/salt selectivity. • The PDA@POPM membrane has good stability and anti-fouling property. Nanochannel membranes derived from porous nanomaterials are crucial for driving the development of advanced desalination and water treatment membranes. However, the practical application of polymer nanochannel membranes is halted by the tedious and complicated preparation and the lack of stability in aqueous service process. In this work, we synthesized a novel type of polydopamine modified imidazolium containing porous organic polymer nanoparticles (PDA@POP), which has good water dispersibility and interface adhesion capability. The PDA@POP aqueous dispersion solution was dip coated on the polysulfone ultrafiltration supporting layer, and the nanocoating was further crosslinked with 1,3,5-Benzenetricarboxylic chloride. The appropriate surface modification of POP nanoparticles with PDA enhances the interfacial interaction and maintains effective-aperture structure, leading to stiff and continuous nanochannels facilitating the water molecules and salt ions quickly transporting through the PDA@POPM membrane. As such, both the water permeability (∼57.0 L·m−2·h−1·bar−1) and dye/salt selectivity (>24) of PDA@POPM are improved 5–10 times higher than that of conventional polymer nanofiltration membranes. Meanwhile, the membrane exhibits good stability and anti-fouling property in long-term dye desalination process. This work provides a convenient and universal strategy to design and manufacture nanochannel membranes with high separation performance. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) membranes have been proposed for water treatment. GO can be used to prepare membranes that remove organic molecules, such as model dyes from contaminated wastewater. In practical applications, wastewater is often acidic or alkaline. The physico-chemical properties of GO are only weakly affected by pH, and this can lead to poor membrane performance for the removal of positively charged model compounds. In this work, we used pH-responsive poly (methacrylic acid) (PMAA) to prepare GO-PMAA materials through chemical crosslinking. GO-PMAA materials with different compositions were used to prepare membranes via physical intercalation. The membranes were tested for removal of five different dyes of different sizes and valency (including those that are positively charged, negatively charged, and neutral at neutral pH). We identify a membrane composition that works well for the removal of negatively charged methyl orange and Evans blue under acidic conditions (with 73.1% and 99.7% rejection, respectively) with improved water permeance compared to membranes prepared with GO alone. In addition, we evaluated the long-term stability of the nanofiltration membrane. After continuous operation for 20 h, the rejection rate of MnB by 5p-nGOM was about 85.37%, and the water permeance relatively stable, while the rejection rate of MnB by nGOM was about 26.59%, and the water permeance changed greatly. These findings indicate that GO membranes modified with pH-responsive polymers can achieve superior performance with respect to separation, water permeance, long-term operation, and pressure resistance, compared to GO membranes. • GO-PMAA composites were prepared by chemical cross-linking method. • GO-PMAA materials with different compositions were used to prepare membranes via physical intercalation. • Preparation of pH-responsive composite membranes. • The pH-responsive composite membrane exhibited good rejection of negatively charged dyes (MO and EB) under acidic conditions. [ABSTRACT FROM AUTHOR]

Two-dimensional covalent triazine framework material (2D-CTF) is a kind of covalent organic framework material with triazine ring structure consisting of C and N elements, which is considered to be a type of ideal membrane material due to its excellent structural stability and adjustable in-plane nanopore. In this study, few-layers 2D-CTF-1 nanomaterials were prepared using a micro-interface method based on the polymerization of 1,4-dicyanobenzene. The resulting few-layers 2D-CTF-1 nanosheets were used as building blocks to construct 2D-CTF-1 membrane via a layer-bylayer assembly method. The structure and morphology of the prepared 2D-CTF-1 nanosheets and membrane were characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy, transmission electron microscopy and scanning electron microscopy. The pure water flux under different pressures and the separation performances of 2D-CTF-1 membrane for small organic dye molecules were tested. The results show that 2D- CTF-1 membrane possesses high pure water flux(153.7 L/(m2·h)) (25 °C, 0.1 MPa), and the in-plane nanopores of 2D-CTF-1 are proposed as the main transport channels for water molecules. Besides, the 2D-CTF-1 membrane exhibits high flux (132.5 L/(m2·h)) (25 °C, 0.1 MPa) and high rejection rate (98.3%) for separation of organic dye (Congo red). The membrane still shows high flux and rejection after a long-term operation. Thus, 2D-CTF-1 is a promising 2D separation membrane material for high efficient molecular separation. [ABSTRACT FROM AUTHOR]

In the agricultural production and processing industry, technological processes in which electroactivated water and solutions based on it are effectively used are very widespread. The development of installations for the electroactivation of water and the optimization of operating modes are undoubtedly topical issues, the solution of which will make it possible to use them more effectively in agricultural practice. The results have been presented of studying the operational characteristics of a nonflowing device for the electroactivation of tap water both with an unchanged area of the separation membrane between the anode and cathode compartments and when this area changes its dimensions. Studies have made it possible to establish that, at a constant value of the working area of the separation membrane, the minimum consumption of electricity corresponds to the smallest interelectrode distance. Approaches for implementing effective operation of the electrotechnological installation are proposed. [ABSTRACT FROM AUTHOR]

• Nanocellulose based membrane with ultrathin graphene oxide top layer was developed. • Ultrahigh flux (18,123 Lm−2h−1 bar−1) attributable to water transport nanochannels. • Membranes had excellent dry and wet mechanical properties. • Efficient retention of dyes (92%–99%) via adsorption and size exclusion. • The layered structure impacts membrane functionality. Ultrathin graphene oxide (GO) layer was fabricated on cellulose nanofiber (CNF) membrane to achieve robust crosslinker free layered membrane with synergistic water flux and separation performance. Unlike pristine cellulosic or GO membranes, GO-CNF hybrid membranes exhibited significantly improved mechanical stability in both dry and wet states. All membranes showed negative surface zeta potential. GO: CNF membrane (1:100) exhibited significantly high water flux (18,123 ± 574 Lm−2 h−1 bar−1); higher than that of CNF membrane or the hydrophilic commercial reference membrane with comparable pore structure (Nylon 66, 0.2 μm). We hypothyse that a unique surface structure of "standing inserted GO nanosheets" observed at low concentrations of GO contributes enormously to its ultrafast water permeability through creation of numerous water transport nanochannels. The aniosptropic layered membranes exhibited >90% rejection of positively and negatively charged dyes through a combination of electrostatic interaction, hydrophobic interactions and molecular size exclusion. Construction of an ultrathin GO layer on CNF offers a unique and efficient way to prepare highly functional, economical and scalable water purification membranes having significant advantage with respect to flux, mechanical stability and rejection of dyes compared to isotropic membrane with GO nanosheets randomly dispersed in the cellulose nanofibrous network. [ABSTRACT FROM AUTHOR]

Application of DNA to photonics and electronics was proposed by Naoya Ogata in 1990s. Utilizing its specific structure, ability to complex formation, and affinity to various organics, many types of complex materials have been synthesized and reformed with various techniques by Ogata and his collaborators, showing promising functionalities for practical applications. Application field ranged over very wide area from photonics as dye laser, nonlinear optics, photonic switch, electroluminescence, and optical waveguide device to biological and medical applications. Research activities on DNA materials are still expanding at the moment. This review aims to give a concise overview of his pioneering works in this new field and their impacts on science and engineering. [ABSTRACT FROM AUTHOR]

Water pollution is a serious problem around the world. It causes the lack of clean drinking water and brings risks to human health. Membrane technology has become a competitive candidate to treat the contaminated wastewater due to its high separation efficiency and low energy consumption. In this review, we introduce the recent development of several kinds of bioinspired separation membranes, involving the membrane design and applications. We emphasize the multi-phase liquid separation membranes inspired from nature with special wettability applied for oil/water separation, organic liquids mixture separation, and emulsion separation. After separating multi-phase liquids using these membranes, small molecule pollutants still exist in single-phase liquid. Therefore, we also expand the scope to small molecule-scale separation membranes, such as the nacre-like graphene oxide separation membrane and other nanofiltration membranes. Summary and outlook concerning the future development of separation membranes are also introduced briefly. [ABSTRACT FROM AUTHOR]

Due to its superior characteristics？ such as tailoring framework structure？ high specific area？ high porosity? adjustable chemical and thermal properties ？ metal-or ganic frameworks (MOFs) have attracted much attention in the areas of absorption，sensors？ catalyst and separation, etc. Based on the introduction of preparation methods for MOFs arid membranes containing MOFs？ in the paper，the effects of MOFs？ such as functional group ？ particle size ？ morphology, pore size ？ dosage and other influence factors on the performances of the membranes were emphasized. The future research trends of the MOFs membrane were also suggested. [ABSTRACT FROM AUTHOR]

In this study, a new monitoring method was developed, titled infrared thermal imaging technology, which can effectively evaluate the thermal effect of the charge-discharge test in the vanadium/iodine redox flow battery (V/I RFB). The results show that the all-vanadium redox flow battery (all-V RFB) has a greater molar reaction Gibbs free energy change than that of the V/I RFB, representing a large thermal effect of the all-V RFB than the V/I RFB. The charge-discharge parameters, flow rate and current density, are important factors for inducing the thermal effect, because of the concentration polarization and the ohmic resistor. The new membrane (HS-SO3H) shows a high ion exchange capacity and a good ions crossover inhibitory for the V/I RFB system, and has a high coulomb efficiency that reaches 96%. The voltage efficiency was enhanced from 61% to 86% using the C-TiO2-Pd composite electrode as a cathode with the serpentine-type flow field for the V/I RFB. By adopting the high-resolution images of an infrared thermal imaging technology with the function of the temperature profile data, it is useful to evaluate the key components’ performance of the V/I RFB, and is a favorable candidate in the developing of the redox flow battery system.

Covalent organic polymers (COPs) with abundant micropores are deemed as promising materials for building molecular separation membranes. In spite of this potential, fabricating COP separation membranes through an efficient and scalable method remains a significant challenge. Herein, we report a simple and efficient strategy for the synthesis of COP membranes with three-dimensionally interconnected micropores. Utilizing transition-metal nitrates as a catalyst, we achieve fast polymerization of amorphous COPs with relatively uniform micropores (0.7 nm in diameter). The rational design of organic-aqueous interface allows for the direct fabrication of robust COP membranes with an ultrathin thickness of ∼20 nm on porous polyacrylonitrile substrates. The resulting hydrophobic but pore-uniform frameworks in these membranes permit fast permeation of organic liquids with a notable molecular weight cutoff of 388 g mol−1 in ethanol. To demonstrate scalability, we show that our strategy can produce large-size COP membranes with a prominent area of 200 cm2, which exhibit performances similar to that of small membrane coupons. The present study offers a potentially scalable method for producing highly microporous COP membranes toward efficient molecular separation in organic liquids. [Display omitted] • A three-dimensional COP with uniform and subnanometer pores is synthesized. • Ultrathin COP membranes are rapidly prepared at ambient conditions. • The optimal COP membrane shows high selectivities with decent solvent permeances. • We produce large-size COP membranes without losing their separation performance. [ABSTRACT FROM AUTHOR]

The efficiency of CO 2 capture using a hollow fiber membrane containing 2-(2-Aminoethylamino) ethanol (AEEA) from the emission gas in the Integrated Gasification Combined Cycle (IGCC) was investigated by density functional theory and fluid dynamics. A reaction path for CO 2 sorption to AEEA involving two H 2 O molecules with three – proton transfer was found to give the low barrier of the reaction due to 6 intermolecular hydrogen bonds which make the transition state structure more stable. The activation energy in the reaction path for CO 2 sorption to AEEA was 7.11 kcalmol−1 which is approximately 10 kcalmol−1 lower than that involving one H 2 O molecule with two – proton transfer discussed in our previous study (Higashino et al., 2023). Since the activation energy is much lower than those in the other reaction paths we have investigated, it can occur much more frequently than others when sufficient moisture is maintained in the membrane. The estimated reaction rate k = 3.407 × 108 s−1 indicates that CO 2 becomes carbamate by reaction with AEEA as soon as reaching the surface of the membrane, and thus, CO 2 attachment to AEEA cannot be the rate limiting. Since flow in the hollow fiber membrane can be laminar, simulated CO 2 permeance for the temperature of 358 K and the pressure of 2.4 MPa has a range from 10−10 to 10−9 m3 (STP) m−2s−1Pa−1, which is a few orders smaller than that for the flat sheet membrane, flow over which is turbulent, i.e.10−8 to 10−7 m3(STP) m−2s−1Pa−1 (Higashino et al., 2023). Overall, the reaction rate of CO 2 attachment to AEEA is sufficiently large, and hence, any one of mass transfer of CO 2 induced by turbulence (turbulent flow), molecular diffusion of CO 2 from feed gas to the membrane surface (laminar flow), and molecular diffusion of bicarbonate (HCO 3 -) from the feed side to the permeate side in the membrane can be the rate limiting depending on which type of membrane, e.g. a flat sheet membrane module, a spiral membrane module, a hollow fiber membrane contactor, etc., is used for CO 2 capture. [Display omitted] • Flow in a hollow fiber membrane with inner diameter of a few millimeters can be laminar. • CO 2 sorption to AEEA is so fast due to three proton transfer and thus cannot be rate limiting. • Either CO 2 transfer from feed gas to membrane or molecular diffusion of bicarbonate in membrane can be rate limiting. • CO 2 permeance dramatically increases if flow becomes from laminar to turbulent. [ABSTRACT FROM AUTHOR]

[Display omitted] • The formation mechanism and characteristics of MPN are summarized. • MPN-engineered strategies include co-deposition and secondary modification. • Separation, catalysis, and adsorption applications by MPN-engineered membranes. • The future exploration direction of multifunctional MPN-engineered membranes. Metal-phenolic network (MPN) is a kind of supramolecular material formed by the complexation of metal ions and organic ligands, and is widely used due to its extensive adhesive properties and simple operation methods. At present, MPN has been successfully applied in the surface modification of separation membrane materials, but there is still a lack of comprehensive reviews of separation membranes constructed by MPN, including construction methods and different applications. This paper emphasizes the formation mechanism and characteristics of MPN and MPN-based engineering strategies for the fabrication of multifunctional MPN-engineered membranes. The application of MPN-engineered membranes in water treatment is mainly introduced, including separation (molecular sieving and oil–water separation), catalysis (degradation of organic pollutants), and adsorption (dye adsorption and heavy metal adsorption). Given the limitations of current MPN functional membranes, the prospects for developing ultra-thin and durable MPN-engineered functional membranes are presented. This review has reference significance for the fields of water treatment and other energy and environment-related applications. [ABSTRACT FROM AUTHOR]

A graphene oxide (GO) nanosheet with epoxy groups was prepared by exfoliating the graphite oxide. The free standing membrane of the GO nanosheet with epoxy groups was used for water purification, which showed higher water selectivity from NaCl aqueous solution compared with conventional GO membrane with various oxygen functional groups such as carboxyl, hydroxyl, and epoxy groups, indicating that the epoxy groups on the GO nanosheet suppress the permeation of ions. [ABSTRACT FROM AUTHOR]

Two-dimensional membranes have shown promising potential for ion-selective separation due to their well-defined interlayer channels. However, the typical "trade-off" effect of throughput and selectivity limits their developments. Herein, we report a precise tailoring of monovalent cation sieving technology with enhanced water throughput via the intercalation of graphene-oxide membranes with selective crown ethers. By tuning the lamellar spacing of graphene oxide, a critical interlayer distance (∼11.04 Å) is revealed to maximize water flux (53.4 mol m -2 h -2 bar -1 ) without sacrificing ion selectivity. As a result, the elaborately enlarged interlayer distance offers improved water permeance. Meanwhile, various specific cations with remarkably high selectivity can be separated in mixed solutions because of the strong chelation with crown ethers. This work opens up a new avenue for high-throughput and precise regulation of ion separations for various application scenarios.

Tough gel membrane composed of a large amount of an ionic liquid and an inorganic/organic composite double-network (inorganic/organic DN ion gel membrane) was examined to remove toluene vapor from toluene vapor/N2 mixed gas. The DN ion gel membrane with 80 wt% of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide showed higher toluene vapor permeability (more than 30,000 barrer) and toluene vapor/N2 permselectivity (690) than the supported ionic liquid membrane. The toluene vapor permeability and toluene vapor/N2 permselectivity were maintained under pressurized condition. It was confirmed that the toluene vapor permeation was limited by intramembrane diffusion of the dissolved toluene vapor. [ABSTRACT FROM AUTHOR]

Polystyrene membranes with precisely controlled and vertically oriented pores are fabricated by a bidirectional freezing process. In this process, the influence of polymer in growth of diphenyl sulfone (DPS) crystals has been demonstrated by XRD and simulated by DFT based on the interaction between DPS crystal faces and polystyrene (PS). The influence of temperature gradient on membrane structures is also elucidated. Compared to the original membrane and modified traditional membranes, modified PS membranes with vertically oriented pores show large and stable fluxes in the processes of multiple oil and water separation. [ABSTRACT FROM AUTHOR]