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Extreme confinement in nanochannels results in unconventional equilibrium and flow behavior of polymers. The underlying flow physics dictating such paradigms remains far from being understood and more so if the confining substrate is composed of two-dimensional materials, such as graphene. In this study, we conducted systematic molecular dynamics simulations to explore the effect of wettability, confinement, and chain length on polymer flow through graphene-like nanochannels. Altering the wetting properties of these membranes that structurally represent graphene results in substantial changes in the behavior of polymers of disparate chain lengths. Longer hydrocarbon chains (n-dodecane) exhibit negligible wettability-dependent structuring in narrower nanochannels compared to shorter chains (n-hexane) culminating in higher average velocities and interfacial slippage of n-dodecane under less wettable conditions. We demonstrate that the wettability compensation comes from chain entanglement attributed to entropic factors. This study reveals a delicate balance between wettability-dependent enthalpy and chain-length-dependent entropy, resulting in a unique nanoscale flow paradigm, thus not only having far-reaching implications in the superior discernment of polymeric flow in sub-micrometer regimes but also potentially revolutionizing various applications in the oil industry, including innovative oil transport, oil extraction, ion transport polymers, and separation membranes. [ABSTRACT FROM AUTHOR]

This study investigated the potential application of geopolymeric material for the separation of oil-in-water emulsions in wastewater treatment. For the first time, an asymmetric membrane made of geopolymers was developed for this specific separation process. The performances of the geopolymeric membrane in oil separation were compared with those obtained by a commercial ceramic membrane. The study also aimed at exploring the effects of emulsion formulation and emulsion properties (surfactant type and concentration, pH, and zeta potential) and membrane parameters (surface charge and material) on permeate volumetric flux and chemical oxygen demand (COD) rejection. Emulsions were prepared using 3% (w/v) dodecane oil in distilled water, with surfactant concentrations of 1x and 10x critical micelle concentration (CMC) and three surfactants of different nature (Oleth-10, Brij 76, and CTAB) at pH values of 2, 5, and 8. Results showed that for the best operating conditions of the geopolymeric membrane, initial and final permeate flux values of 42 and 26 L h−1 m−2, respectively, were achieved. COD rejection values ranged from 95.0 to 99.4% using the geopolymeric membrane thus indicating a very similar behavior between geopolymeric and ceramic membranes. These findings suggest that geopolymers are promising to produce membranes for oil-in-water emulsion microfiltration, promoting an interesting alternative for the treatment of industrial wastewater more sustainable in terms of environmental effects and costs compared to ceramic membranes. • Novel geopolymeric asymmetric membrane was synthetized. • Geopolymer selective layer was successfully deposited on pressed geopolymer support. • The geopolymeric membrane showed excellent fluxes and removal efficiencies. • Flux and rejection properties vary with surfactant concentration and emulsion pH. • Geopolymer membrane performs similarly to a commercial microfiltration ceramic one. [ABSTRACT FROM AUTHOR]

There are many advantages of using membranes in the separation of wastewater, but their uses are limited because they are not reusable due to blockages in the membrane. In this study, alginate‐based poly(ethyl‐methacrylate) (PEMA) polymeric membranes containing previously synthesized IOS, which are known to be selective against Fe3+, were prepared and their permeability against heavy metals such as Cd2+, Co2+, Cu2+, Fe3+, Hg2+ and Pb2+ were investigated. The properties of membranes characterized by UV‐Vis and FT‐IR spectrophotometry, were investigated with analysis techniques such as SEM, contact angle measurements, TG‐DTG, DSC and AFM. As a result of the measurements taken from the UV spectrophotometer of the filtrates passed through various aqueous ion solutions of the membranes as mentioned above, it was concluded that the ion to which the membrane was most selective was the Fe3+ ion. Moreover, it could be said that thanks to the repeated filtration processes the membrane prepared retained some Fe3+ ion in each measurement and could be used many times in the filtration process. Resultantly, it is possible to say that the polymeric Fe3+ membrane sensor produced may be suitable for use when it is necessary to remove Fe3+ ion from a polluted aqueous environment. [ABSTRACT FROM AUTHOR]

Membranes on palladium alloy basis with surface modified by nanoparticles with high catalytic activity are useful in deep hydrogen purification and single-stage process of high-purity hydrogen production. This paper reports the development and improvement of methods for synthesis of Pd-based pentatwinned nanoparticles of strictly specified morphology with certain shapes, facets and composition. The competing effect of surfactants and optimization of the halide ions ratio in solution make it possible to direct a particle growth towards formation of pentatwinned Pd-nanostars. Pd–23%Ag coatings synthesized on the surface showed uniquely high peak current density of up to 238 mA cm−2 in alkaline methanol oxidation reaction. This is due to both increased surface area and greater catalytic activity of nanostars' facets. A record increase in hydrogen permeability of up to 12.5 mmol s−1 m−2 at 100 °C has been achieved for palladium-silver membranes with modified surface. This indicates an acceleration of sorption/desorption stages. The developed method for controlling morphology of nanoscale coatings opens the way to the production of membrane hydrogen filters, which operate at room temperature. [Display omitted] • Surface-modified Pd membranes are an excellent tool for high-purity hydrogen production. • Approaches have been developed to manipulate the processes of morphology fine-tuning of Pd nanostars. • Modified Pd–Ag films exhibited high peak current density up to 238 mA cm−2 in methanol electrooxidation. • A record flux density up to 12.5 mmol s−1m−2 at 100 °C has been demonstrated in membrane hydrogen purification process. • Modified membranes open up the possibility of deep hydrogen purification at low temperatures. [ABSTRACT FROM AUTHOR]

Hydrogen has received great attention as a carbon-free and clean energy source. General industrial processes of hydrogen production involve the separation of gas mixtures to fulfil the purity requirement for most practical applications. Among various separation technologies, membrane separation based on proton-conducting ceramics has been shown to be a very promising method duo to reduced energy consumption and high purity. This review covers the key aspects of hydrogen separation using proton ceramic membranes, including the two main types of hydrogen permeation, namely electrochemical hydrogen pumping based on pure proton conduction, as well as spontaneous hydrogen permeation based on mixed proton-electron conducting membranes. In addition, the challenges facing hydrogen separation technology via proton ceramic membrane and the key issues yet to be solve are summarized. This review aims to provide a reference for the future development and application of this technology. • Systematic review of ceramic hydrogen membranes: proton conduction, separation processes, and key factors. • Detailed overview of electrochemical ceramic hydrogen pump research: materials, electrodes, structures. • Discussion on state-of-the-art results and optimization for hydrogen separation via mixed proton-electron membranes. • Highlighting important, underexplored aspects of proton ceramic membranes for hydrogen separation. [ABSTRACT FROM AUTHOR]

Oil spills and industrial wastewater discharge have inflicted severe damage upon the ecological environment and human health. Therefore, the development of an environmentally friendly and pollution-free membrane material for oil-water separation is imperative. This study presents the development of a novel oil-water separation material (PP-PPy-pHR) that is environmentally benign and capable of switching between wetting properties. The material was synthesised by dopamine modification, treatment with a pH-responsive polymer and the use of a high-efficiency photothermal layer composed of self-assembled polypyrrole (PPy), and it not only separates incompatible oil-water mixtures but also efficiently separates oil-water emulsions under different pH conditions. Due to the good photothermal effect of PPy, the evaporation rate of PP-PPy-pHR composite membrane loaded with PPy was 3.95 times higher than that of pure water for oily wastewater. In addition, the PPy-pHR composite membrane exhibited excellent durability and high stability in extremely acidic and alkaline solutions, showing remarkable potential for oil-water separation applications. [ABSTRACT FROM AUTHOR]

Polymer membranes are widely used for gas separation, addressing critical environmental and energy issues. Nevertheless, crafting high‐performance polymer membranes remains a challenging task, often relies on labor‐intensive trial‐and‐error experiments. Different from the traditional Edisonian approach, machine learning offers significant potential to expedite the design of new polymer membranes for gas separation, yet it faces a substantial hurdle due to limited data availability. To overcome this challenge, in this study two physics‐informed performance metrics are introduced, namely fractional free volume and average void size, to assess the separation performance of polymer membranes. By employing active learning and multi‐target screening, top‐performing polyimides with intrinsic microporosity are efficiently discovered from a pool of 155 610 candidates, through calculations of only 709 (0.45%) in the entire search space. As validated by molecular simulations, the top‐performing polyimides exhibit exceptional separation performance for CO2/N2, CO2/CH4, and O2/N2 mixtures, superior to existing polymers and surpassing the current upper bound. The utilization of physics‐informed performance metrics provides a novel strategy to advance the design and accelerate the discovery of new polymer membranes for gas separation and many other important applications. [ABSTRACT FROM AUTHOR]

This work presents methods of obtaining polymeric hollow-fiber membranes produced via the dry–wet phase inversion method that were published in renowned specialized membrane publications in the years 2010–2020. Obtaining hollow-fiber membranes, unlike flat membranes, requires the use of a special installation for their production, the most important component of which is the hollow fiber forming spinneret. This method is most often used in obtaining membranes made of polysulfone, polyethersulfone, polyurethane, cellulose acetate, and its derivatives. Many factors affect the properties of the membranes obtained. By changing the parameters of the spinning process, we change the thickness of the membranes' walls and the diameter of the hollow fibers, which causes changes in the membranes' structure and, as a consequence, changes in their transport/separation parameters. The type of bore fluid affects the porosity of the inner epidermal layer or causes its atrophy. Porogenic compounds such as polyvinylpyrrolidones and polyethylene glycols and other substances that additionally increase the membrane porosity are often added to the polymer solution. Another example is a blend of two- or multi-component membranes and dual-layer membranes that are obtained using a three-nozzle spinneret. In dual-layer membranes, one layer is the membrane scaffolding, and the other is the separation layer. Also, the temperature during the process, the humidity, and the composition of the solution in the coagulating bath have impact on the parameters of the membranes obtained. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) have aroused colossal attention in the fabrication of nanocomposite membranes ascribed to their ultra-small size, good dispersibility, biocompatibility, excellent fluorescence, facile synthesis, and ease of functionalization. Their unique properties could significantly improve membrane performance, including permeance, selectivity, and antifouling ability. In this review, we summarized the recent development of CDs-based nanocomposite membranes in many application areas. Specifically, we paid attention to the structural regulation and functionalization of CDs-based nanocomposite membranes by CDs. Thus, a detailed discussion about the relationship between the CDs' properties and microstructures and the separation performance of the prepared membranes was presented, highlighting the advantages of CDs in designing high-performance separation membranes. In addition, the excellent optical and electric properties of CDs enable the nanocomposite membranes with multiple functions, which was also presented in this review. [ABSTRACT FROM AUTHOR]

A parametric evaluation on a series of oxygen-deficient Co-rich La0.5Sr0.5Co0.8Fe0.2−xCuxO3−δ perovskite oxides (x = 0–0.20) is reported, for potential utility towards oxygen separation membrane and fuel cell application. Oxygen transport property is influenced by several parameters, including oxygen vacancy concentration, crystal structure, microstructure, electrical conductivity, and conductivity relaxation. X-ray photoelectron spectroscopy study revealed that oxygen nonstoichiometry in the prepared oxides increases with Cu-substitution level. The structural study confirmed that this material family has a cubic structure with Pm 3 - m space group with lattice size decreasing with increase in x. The microstructure of studied oxides showed that the average grain size of the sample considerably decreases with Cu-substitution. Iron substitution with copper remarkably enhances the electrical conductivity, which can be explained with defect chemistry. The bulk diffusion coefficient (Dchem) and surface exchange coefficient (Kchem) of La0.5Sr0.5Co0.8Fe0.2−xCuxO3−δ oxides were obtained using an electrical conductivity relaxation technique, and La0.5Sr0.5Co0.8Cu0.2O3−δ oxide was found to have higher Dchem (1.1 × 10−4 cm2 s−1) and Kchem (8.5 × 10−5 cm s−5) among them. This work demonstrates that the proposed Co-rich La0.5Sr0.5Co0.8Fe0.2−xCuxO3−δ perovskite with Cu-substitution level x = 0.20 can be considered a promising material for enhanced oxygen transport. [ABSTRACT FROM AUTHOR]

Different drying methods were used to prepare catalytic membranes for the simultaneous removal of dust and NO to explore their effect on the distribution of active components, with the structural properties, filtration performance, catalytic performance, and working mechanism of the preferred prepared catalytic membrane systematically investigated. The results indicated that microwave drying, in contrast to traditional electric drying with blasting, effectively inhibited the migration of the precursor solution to achieve uniform loading of active components, thus endowing the catalytic membrane with excellent catalytic activity. Meanwhile, the pore structure of the fibrous ceramic substrate was not almost affected by the loaded catalyst and still exhibited high porosity. These characteristics contributed to the development of a catalytic membrane with good filtration and catalytic performance, as well as superior adaptable NO concentration and filtration velocity properties. Therefore, fibrous ceramic-based catalytic membranes prepared using microwave assistance offer considerable application prospects for integrated purification of high-temperature flue gases. Furthermore, the removal of dust and NO was determined to follow the Eley–Rideal reaction mechanism and surface filtration mechanism of the residual dust cake, respectively. [ABSTRACT FROM AUTHOR]

Accurate quantification of nano-selenium (nSe) and other ionic Se species in aquatic environments is a prerequisite for reliable estimation of their potential hazards. In this study, a micropore membrane filtration–based method followed by ICP-MS analysis was proposed for the selective concentration and determination of nSe in the water column. Polyvinylidene fluoride (PVDF) and nylon micropore filtration membranes were proven to efficiently capture nSe under optimal conditions (retention > 91.0 ± 0.87%). At the same time, ionic selenite and selenate could escape from the membranes, realizing the isolation of nSe and ionic Se species. The interference of dissolved organic matter (DOM) during separation can be resolved by adding Ca(II) ions, which can induce the formation of DOM aggregates by cation bridging effects. nSe retained on PVDF membranes could be effectively eluted with FL-70 (a powerful alkaline surfactant) aqueous solutions (0.5%, m/v) while maintaining the original size and morphology. Although nSe trapped on nylon membranes could not be easily eluted, quantification can also be achieved after membrane digestion. Speciation of ionic selenite and selenate in the filtrate was further conducted with an anion exchange column by using HPLC coupled with ICP-MS. The developed method was used to analyze Se species in six real water samples. Spiking experiments showed that the recoveries of nSe ranged from 70.2 ± 2.7% to 85.8 ± 1.3% at a spike level of 0.2 µg/L, and the recoveries of Se(IV) and Se(VI) ranged from 83.6 ± 0.5% to 101 ± 1% at a spike level of 0.55 µg/L, verifying the feasibility for the analysis of environmental water samples. This work provides possibilities to investigate the transformation and potential risks of nSe in the environment. [ABSTRACT FROM AUTHOR]

Through enabling whole blood detection in point-of-care testing (POCT), sedimentation-based plasma separation promises to enhance the functionality and extend the application range of lateral flow assays (LFAs). To streamline the entire process from the introduction of the blood sample to the generation of quantitative immune-fluorescence results, we combined a simple plasma separation technique, an immunoreaction, and a micropump-driven external suction control system in a polymer channel-based LFA. Our primary objective was to eliminate the reliance on sample-absorbing separation membranes, the use of active separation forces commonly found in POCT, and ultimately allowing finger prick testing. Combining the principle of agglutination of red blood cells with an on-device sedimentation-based separation, our device allows for the efficient and fast separation of plasma from a 25-µL blood volume within a mere 10 min and overcomes limitations such as clogging, analyte adsorption, and blood pre-dilution. To simplify this process, we stored the agglutination agent in a dried state on the test and incorporated a filter trench to initiate sedimentation-based separation. The separated plasma was then moved to the integrated mixing area, initiating the immunoreaction by rehydration of probe-specific fluorophore-conjugated antibodies. The biotinylated immune complex was subsequently trapped in the streptavidin-rich detection zone and quantitatively analyzed using a fluorescence microscope. Normalized to the centrifugation-based separation, our device demonstrated high separation efficiency of 96% and a yield of 7.23 µL (= 72%). Furthermore, we elaborate on its user-friendly nature and demonstrate its proof-of-concept through an all-dried ready-to-go NT-proBNP lateral flow immunoassay with clinical blood samples. [ABSTRACT FROM AUTHOR]

Inorganic zeolites have excellent molecular sieving properties, but they are difficult to process into macroscopic structures. In this work, we use metal–organic framework (MOF) glass as substrates to engineer the interface with inorganic zeolites, and then assemble the discrete crystalline zeolite powders into monolithic structures. The zeolites are well dispersed and stabilized within the MOF glass matrix, and the monolith has satisfactory mechanical stabilities for membrane applications. We demonstrate the effective separation performance of the membrane for 1,3‐butadiene (C4H6) from other C4 hydrocarbons, which is a crucial and challenging separation in the chemical industry. The membrane achieves a high permeance of C4H6 (693.00±21.83 GPU) and a high selectivity over n‐butene, n‐butane, isobutene, and isobutane (9.72, 9.94, 10.31, and 11.94, respectively). This strategy opens up new possibilities for developing advanced membrane materials for difficult hydrocarbon separations. [ABSTRACT FROM AUTHOR]

Inorganic zeolites have excellent molecular sieving properties, but they are difficult to process into macroscopic structures. In this work, we use metal–organic framework (MOF) glass as substrates to engineer the interface with inorganic zeolites, and then assemble the discrete crystalline zeolite powders into monolithic structures. The zeolites are well dispersed and stabilized within the MOF glass matrix, and the monolith has satisfactory mechanical stabilities for membrane applications. We demonstrate the effective separation performance of the membrane for 1,3‐butadiene (C4H6) from other C4 hydrocarbons, which is a crucial and challenging separation in the chemical industry. The membrane achieves a high permeance of C4H6 (693.00±21.83 GPU) and a high selectivity over n‐butene, n‐butane, isobutene, and isobutane (9.72, 9.94, 10.31, and 11.94, respectively). This strategy opens up new possibilities for developing advanced membrane materials for difficult hydrocarbon separations. [ABSTRACT FROM AUTHOR]

A good integration of the polymer materials that form a mixed-matrix membrane (MMM) for gas separation is essential to reaching interesting permselective properties. In this work, a porous polymer network (PPN), obtained by combining triptycene and trifluoroacetophenone, has been used as a filler, which was blended with two o-hydroxypolyamides (HPAs) that act as polymer matrices. These polymer matrices have been thermally treated to induce a thermal rearrangement (TR) of the HPAs to polybenzoxazoles (β-TR-PBOs) through a solid-state reaction. For its structural study, various techniques have been proposed that allow us to undertake a morphological investigation into the integration of these materials. To access the internal structure of the MMMs, three different methods were used: a polishing process for the material surface, the partial dissolution of the polymer matrix, or argon plasma etching. The argon plasma technique has not only revealed its potential to visualize the internal structure of these materials; it has also been proven to allow for the transformation of their permselective properties. Force modulation and phase contrast in lift-mode techniques, along with the topographic images obtained via the tapping mode using a scanning probe microscope (SPM), have allowed us to study the distribution of the filler particles and the interaction of the polymer and the filler. The morphological information obtained via SPM, along with that of other more commonly used techniques (SEM, TGA, DSC, FTIR, WASX, gas adsorption, and permeability measurements), has allowed us to postulate the most probable structural configuration in this type of system. [ABSTRACT FROM AUTHOR]

In recent decades, the interest in responsive fibrous structures has surged, propelling them into diverse applications: from wearable textiles that adapt to their surroundings, to filtration membranes dynamically altering selectivity, these structures showcase remarkable versatility. Various stimuli, including temperature, light, pH, electricity, and chemical compounds, can serve as triggers to unleash physical or chemical changes in response. Processing methodologies such as weaving or knitting using responsive yarns, electrospinning, as well as coating procedures, enable the integration of responsive materials into fibrous structures. They can respond to these stimuli, and comprise shape memory materials, temperature-responsive polymers, chromic materials, phase change materials, photothermal materials, among others. The resulting effects can manifest in a variety of ways, from pore adjustments and altered permeability to shape changing, color changing, and thermal regulation. This review aims to explore the realm of fibrous structures, delving into their responsiveness to external stimuli, with a focus on temperature, light, and pH. [ABSTRACT FROM AUTHOR]

Dissolved gases in the aquatic environment are critical to understanding the population of aquatic organisms and the ocean. Currently, laser absorption techniques based on membrane separation technology have made great strides in dissolved gas detection. However, the prolonged water–gas separation time of permeable membranes remains a key obstacle to the efficiency of dissolved gas analysis. To mitigate these limitations, we demonstrated direct measurement of dissolved gas using the evanescent-wave absorption spectroscopy of a tapered silica micro-fiber. It enhanced the analysis efficiency of dissolved gases without water–gas separation or sample preparation. The feasibility of this sensor for direct measurement of dissolved gases was verified by taking the detection of dissolved ammonia as an example. With a sensing length of 5 mm and a consumption of ~50 µL, this sensor achieves a system response time of ~11 min and a minimum detection limit (MDL) of 0.015%. Possible strategies are discussed for further performance improvement in in-situ applications requiring fast and highly sensitive dissolved gas sensing. [ABSTRACT FROM AUTHOR]

A disc ceramic membrane was modified nano-TiO 2 via an impregnation and in-situ hydrolysis method, resulting in the generation of nano-TiO 2 particles on the surface and inside the pores of disc ceramic membrane. The uniform distribution of nano-TiO 2 enhanced the superior hydrophilic property of the membrane surface, and improved pure water flux and increased anti-fouling capacity. The modified disc ceramic membrane was employed to effectively separate stable oil-water emulsions under dynamic membrane filtration mode. Here, the preparation process of nano-TiO 2 and operational parameters of equipment on the separation efficiency of the modified disc ceramic membrane were investigated. The findings indicate that an increase in the permeability and separation rate of the modified disc ceramic membrane. Moreover, the modified disc ceramic membrane maintained a steady flux for a continuous separation time of 120-min at a TMP of 0.04 MPa. The rejection rate of oil-water emulsion also reached 99.9%. The excellent performance of the modified disc ceramic membrane was ascribed to the nano-TiO 2 modification and the dynamic membrane filtration applied together to alleviate membrane fouling, leading to improve the oil-water separation efficiency and permeate flux. This study presents a new technique for the separation of oil-water emulsions with high concentration, achieving outstanding separation stability and cost-effectiveness. [ABSTRACT FROM AUTHOR]

Efficient thin film composite polyamide (PA) membranes require optimization of interfacial polymerization (IP) process. However, it is challengeable owing to its ultrafast reaction rate coupled with mass and heat transfer, yielding heterogeneous PA membranes with low performance. Herein, a non‐isothermal‐controlled IP (NIIP) method is proposed to fabricate a highly permeable and selective PA membrane by engineering IP at the cryogenic aqueous phase (CAP) to achieve synchronous control of heat and mass transfer in the interfacial region. The CAP also enables the phase transition of the aqueous solution from the liquid to solid state, providing a more comprehensive understanding of the fundamental mechanisms involved in different phase states in the IP process. Consequently, the PA membrane exhibits excellent separation performance with ultrahigh water permeance (42.9 L m−2 h−1 bar−1) and antibiotic desalination efficiency (antibiotic/NaCl selectivity of 159.3). This study provides new insights for the in‐depth understanding of the precise mechanism linking IP to the performance of the targeting membrane. [ABSTRACT FROM AUTHOR]

Fast transport of monovalent ions is imperative in selective monovalent ion separation based on membranes. Here, we report the in situ growth of crown ether@UiO-66 membranes at a mild condition, where dibenzo-18-crown-6 (DB18C6) or dibenzo-15-crown-5 is perfectly confined in the UiO-66 cavity. Crown ether@UiO-66 membranes exhibit enhanced monovalent ion transport rates and mono-/divalent ion selectivity, due to the combination of size sieving and interaction screening effects toward the complete monovalent ion dehydration. Specifically, the DB18C6@UiO-66 membrane shows a permeation rate (e.g., K+) of 1.2 mol per square meter per hour and a mono-/ divalent ion selectivity (e.g., K+/Mg2+) of 57. Theoretical calculations and simulations illustrate that, presumably, ions are completely dehydrated while transporting through the DB18C6@UiO-66 cavity with a lower energy barrier than that of the UiO-66 cavity. This work provides a strategy to develop efficient ion separation membranes via integrating size sieving and interaction screening and to illuminate the effect of ion dehydration on fast ion transport. [ABSTRACT FROM AUTHOR]

Crystalline porous materials (CPMs), including covalent organic frameworks (COFs) and metal–organic frameworks (MOFs), are promising materials for advanced separation technologies. However, the challenge of transforming nanoscale CPMs into large‐area functional membranes hinders their application in the membrane separation process. Herein, a self‐standing pure COF (TpPa‐1) nanofiber membrane with high crystallinity, good flexibility, excellent mechanical properties, and scalability is prepared using an electrospinning process and polymer sacrificial template strategy. Subsequently, the COF nanofiber membrane is innovatively used to replace traditional inorganic discs, metal meshes, and polymer membranes as porous supports, and the COF–MOF composite CPM membrane is prepared through the tailorable and confined growth of zeolite imidazolium salt frame‐8 (ZIF‐8) on the surface of the COF membrane and in the gaps of the COF nanofibers. The COF–MOF composite membrane exhibits excellent permeability and significantly enhances separation selectivity for organic dyes. Moreover, MOF and COF form an interpenetrating network structure, and their similar chemical properties improve the interfacial stability between the two phases, giving the COF–MOF composite membrane good long‐term separation performance. This is the first self‐standing composite CPM membrane with excellent molecular sieving performance, which provides new insights into the design of high‐performance and robust composite membranes. [ABSTRACT FROM AUTHOR]

Salmonella enterica serovar Typhi (S. Typhi) is the causative agent of Typhoid fever. Blood culture is the gold standard for clinical diagnosis, but this is often difficult to employ in resource limited settings. Environmental surveillance of waste-impacted waters is a promising supplement to clinical surveillance, however validating methods is challenging in regions where S. Typhi concentrations are low. To evaluate existing S. Typhi environmental surveillance methods, a novel process control organism (PCO) was created as a biosafe surrogate. Using a previous described qPCR assay, a modified PCR amplicon for the staG gene was cloned into E. coli. We developed a target region that was recognized by the Typhoid primers in addition to a non-coding internal probe sequence. A multiplex qPCR reaction was developed that differentiates between the typhoid and control targets, with no cross-reactivity or inhibition of the two probes. The PCO was shown to mimic S. Typhi in lab-based experiments with concentration methods using primary wastewater: filter cartridge, recirculating Moore swabs, membrane filtration, and differential centrifugation. Across all methods, the PCO seeded at 10 CFU/mL and 100 CFU/mL was detected in 100% of replicates. The PCO is detected at similar quantification cycle (Cq) values across all methods at 10 CFU/mL (Average = 32.4, STDEV = 1.62). The PCO was also seeded into wastewater at collection sites in Vellore (India) and Blantyre (Malawi) where S. Typhi is endemic. All methods tested in both countries were positive for the seeded PCO. The PCO is an effective way to validate performance of environmental surveillance methods targeting S. Typhi in surface water. [ABSTRACT FROM AUTHOR]

Nitrogen-doped porous carbon (NPC) has a rich microporous structure and nitrogen-rich units, and its nitrogen-containing group can interact strongly with the PEO chain segment of Pebax, synergistically improving its CO2 adsorption ability and interface compatibility. This work prepared three types of triazine-based NPCs with mesoporous and high N-content and added NPCs to Pebax-2533 to prepare NPC/Pebax-2533 MMMs. The effects of N-type, N-content, and pore structure of NPCs on the gas separation performance of MMMs were studied. Constructing a continuous meso-microporous structure within the membrane and adding alkaline N-containing groups were beneficial for promoting rapid CO2 transport. Among the three NPCs, NPC-1/Pebax MMMs prepared using NPC-1 with the highest N-content (10.91%) and suitable pore structure exhibited the best gas separation performance. To investigate the gas transport mechanism of NPC in MMMs, NPC-1 was added to Pebax-2533 and Pebax-1657. The permeability of 3NPC-1/Pebax-2533 MMMs and 0.5NPC-1/Pebax-1657 MMMs reached 423 Barrer and 178 Barrer, with a CO2/N2 selectivity of 61 and 75.8, respectively, both higher than the Pebax-2533 and Pebax-1657. Adding NPC-1 to Pebax-2533 and Pebax-1657 increased the solubility and diffusivity coefficient of MMMs by 40 ~ 80%, and the gas separation performance did not rapidly decrease after long-term stability of 120 h (15%CO2/N2). Compared with NPC-1/Pebax-1657 MMMs, NPC-1/Pebax-2533 MMMs had higher CO2 permeability, mechanical properties, solubility, and diffusivity coefficient. The above results indicated that NPC was more suitable for Pebax-2533. [ABSTRACT FROM AUTHOR]

The separation of chiral drugs continues to pose a significant challenge. However, in recent years, the emergence of membrane‐based chiral separation has shown promising effectiveness due to its environmentally friendly, energy‐efficient, and cost‐effective characteristics. In this study, we prepared chiral composite membrane via interfacial polymerization (IP), utilizing β‐cyclodextrin (β‐CD) and piperazine (PIP) as mixed monomers in the aqueous phase. The chiral separation process was facilitated by β‐CD, serving as a chiral selective agent. The resulting membrane were characterized using SEM, FT‐IR, and XPS. Subsequently, the chiral separation performance of the membrane for DL‐tryptophan (Trp) was investigated. Lastly, the water flux, dye rejection, and stability of the membrane were also examined. The results showed that the optimized chiral PIP0.5β‐CD0.5 membrane achieved an enantiomeric excess percentage (ee%) of 43.0% for D‐Trp, with a solute flux of 66.18 nmol·cm−2·h−1, and maintained a good chiral separation stability. Additionally, the membrane demonstrated positive performance in the selective separation of mixed dyes, allowing for steady operation over a long period of time. This study offers fresh insights into membrane‐based chiral separations. [ABSTRACT FROM AUTHOR]

The research used polyethersulfone (PES) as a membrane material, polyvinylpyrrolidone (PVP) k30 and polyethylene glycol 400 (PEG 400) as water-soluble additives, and dimethylacetamide (DMAc) as a solvent to prepare hollow-fiber ultrafiltration membranes through a nonsolvent-induced phase separation (NIPS) process. The hydrophilic nature of PVP-k30 and PEG caused them to accumulate on the membrane surface during phase separation. The morphology, chemical composition, surface charge, and pore size of the PES membranes were evaluated by SEM, FTIR, zeta potential, and dextran filtration experiments. The paper also investigated how different spinning solution compositions affected membrane morphology and performance. The separation efficiency of membranes with four different morphologies was tested in single-protein and double-protein mixed solutions. The protein separation effectiveness of the membrane was studied through molecular weight cutoff, zeta potential, and static protein adsorption tests. In addition, the operating pressure and pH value were adjusted to improve ultrafiltration process conditions. The PES membrane with an intact sponge-like structure showed the highest separation factor of 11, making it a prime candidate membrane for the separation of bovine serum albumin (BSA) and lysozyme (LYS). The membrane had a minimal static protein adsorption capacity of 48 mg/cm2 and had excellent anti-fouling properties. When pH = 4, the BSA retention rate was 93% and the LYS retention rate was 23%. Furthermore, it exhibited excellent stability over a pH range of 1–13, confirming its suitability for protein separation applications. [ABSTRACT FROM AUTHOR]

Subvisible particles may be encountered throughout the processing of therapeutic protein formulations. Flow imaging microscopy (FIM) and backgrounded membrane imaging (BMI) are techniques commonly used to record digital images of these particles, which may be analyzed to provide particle size distributions, concentrations, and identities. Although both techniques record digital images of particles within a sample, FIM analyzes particles suspended in flowing liquids, whereas BMI records images of dry particles after collection by filtration onto a membrane. This study compared the performance of convolutional neural networks (CNNs) in classifying images of subvisible particles recorded by both imaging techniques. Initially, CNNs trained on BMI images appeared to provide higher classification accuracies than those trained on FIM images. However, attribution analyses showed that classification predictions from CNNs trained on BMI images relied on features contributed by the membrane background, whereas predictions from CNNs trained on FIM features were based largely on features of the particles. Segmenting images to minimize the contributions from image backgrounds reduced the apparent accuracy of CNNs trained on BMI images but caused minimal reduction in the accuracy of CNNs trained on FIM images. Thus, the seemingly superior classification accuracy of CNNs trained on BMI images compared to FIM images was an artifact caused by subtle features in the backgrounds of BMI images. Our findings emphasize the importance of examining machine learning algorithms for image analysis with attribution methods to ensure the robustness of trained models and to mitigate potential influence of artifacts within training data sets. [ABSTRACT FROM AUTHOR]

The environmental destruction caused by oil pollution has been an inescapable fact, and there is an urgent need for efficient separation materials to solve this problem. Generally speaking, Polyethylene terephthalate (PET) is relatively easy to modify into super-hydrophobic/super-oleophilic membranes due to its hydrophobic ester groups. However, there are some challenges in preparing them as underwater super-oleophobic films. Herein, this paper proposes a two-step coating method for the preparation of underwater super-oleophobic PET films by coating the surface of PET films with silicone to form a cross-linked layer through polymerization (Cross-linking), followed by coating the surface of the cross-linked layer with a fluorinated compound/SiO2 (Coating-F@SiO2). Experiments have shown that the new filter membrane exhibits excellent corrosion resistance and special wettability (> 150°). After 30 filtration cycles, it still maintains excellent oil–water separation efficiency (> 99.9%). This simple method for preparing oil–water separation membrane enriches the treatment process of oil pollution. The large-area and low-cost preparation route also provides a prospect for scalable applications. [ABSTRACT FROM AUTHOR]

The increase in emissions and concentration of carbon dioxide in the atmosphere necessitates the implementation of direct carbon dioxide capture technologies. The article presents the characteristics of a single-stage membrane unit for the direct capture of carbon dioxide from the air. A membrane with a selectivity of α C O 2 / N 2 = 70 and permeability P C O 2 = 108 m 3 (S T P) (m 2 · h · b a r) is chosen as the reference variant. It is demonstrated that increasing the pressure difference in the system by reducing the pressure of the permeate stream results in an improvement of all analyzed parameters. Manipulating both the membrane surface and its CO2 permeability yields similar results. With an increase in permeability or membrane surface area, the proportion of CO2 in the retentate and permeate decreases, while the degree of carbon dioxide recovery increases. However, the energy intensity of the process is a complex issue due to the presence of a local minimum in the obtained characteristics. Therefore, a relationship between the constants of energy intensity values for the separation process on the surface area field and CO2 membrane permeability is presented. The minimum energy intensity of the process obtained is 22.5 k W h / k g C O 2 . The CO2 content in the retentate for all analyses did not exceed 280 ppm. [ABSTRACT FROM AUTHOR]

The potential of bionic-inspired superhydrophobic membranes in the field of oil–water separation is significant. In this study, tannic acid induced the rhombohedral crystal form of ZIF-8 to grow in situ on a nylon membrane, resulting in the formation of a layered micro-nano structure. As a result, we successfully prepared a multifunctional composite membrane with exceptional underwater superoleophobicity and oil anti-adhesion. The composite membrane demonstrated an impressive separation flux for layered oil–water mixtures, reaching up to 4851.2 L m−2 h−1. Furthermore, when dealing with surfactant-free oil-in-water emulsions, the separation efficiency exceeded 99.0%. Because ZIF-8 is positively charged, the composite membrane exhibits different separation fluxes in the presence of different surfactants. For SDS stabilized toluene emulsion in water, the maximum separation flux of the composite membrane is 1307.4 L m−2 h−1. The membrane also has good tolerance to alkali and salt substances and is easy to recycle and reuse. Consequently, the ZIF-8 composite membrane has significant potential in effectively separating oil–water emulsions. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) materials with high chemical stability have attracted intensive interest in membrane design for the separation of organic solvents. As a novel 2D material, polymeric fullerenes (C60)∞ with distinctive properties are very promising for the development of innovative membranes. In this work, we report the construction of a 2D (C60)∞ nanosheet membrane for organic solvent separation. The pathways of the (C60)∞ nanosheet membrane are constructed by sub‐1‐nm lateral channels and nanoscale in‐plane pores created by the depolymerization of the (C60)∞ nanosheets. Attributing to ordered and shortened transport pathways, the ultrathin porous (C60)∞ membrane is superior in organic solvent separation. The hexane, acetone, and methanol fluxes are up to 1146.3±53, 900.4±41, and 879.5±42 kg ⋅ m−2 ⋅ h−1, respectively, which are up to 130 times higher than those of the state‐of‐the‐art membranes with similar dye rejection. Our findings demonstrate the prospect of 2D (C60)∞ as a promising nanofiltration membrane in the separation of organic solvents from macromolecular compounds such as dyes, drugs, hormones, etc. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) materials with high chemical stability have attracted intensive interest in membrane design for the separation of organic solvents. As a novel 2D material, polymeric fullerenes (C60)∞ with distinctive properties are very promising for the development of innovative membranes. In this work, we report the construction of a 2D (C60)∞ nanosheet membrane for organic solvent separation. The pathways of the (C60)∞ nanosheet membrane are constructed by sub‐1‐nm lateral channels and nanoscale in‐plane pores created by the depolymerization of the (C60)∞ nanosheets. Attributing to ordered and shortened transport pathways, the ultrathin porous (C60)∞ membrane is superior in organic solvent separation. The hexane, acetone, and methanol fluxes are up to 1146.3±53, 900.4±41, and 879.5±42 kg ⋅ m−2 ⋅ h−1, respectively, which are up to 130 times higher than those of the state‐of‐the‐art membranes with similar dye rejection. Our findings demonstrate the prospect of 2D (C60)∞ as a promising nanofiltration membrane in the separation of organic solvents from macromolecular compounds such as dyes, drugs, hormones, etc. [ABSTRACT FROM AUTHOR]

The separation and purification of hydrogen play an essential role in the field of new energy. In addition, it has great significance and economic value in recovering hydrogen isotope gas from plasma ash discharge gas faced by nuclear fusion reactors. Here, we studied the rapid separation of hydrogen and helium by electrochemical hydrogen pump (EHP), a new hydrogen separation and purification method. In the experiment of the hydrogen-helium separation, the recovery rate of hydrogen can reach 97.4%, and the proportion of hydrogen can reach 99.99%. Furthermore, the effects of catalyst layer structure, membrane materials and working conditions for its performance were analyzed. This experiment found that proton conduction in the catalyst layer and proton exchange membrane became the speed-control step of the process. Moreover, efficient catalyst layer design and membrane materials with high proton conductivity are beneficial to improve EHP's performance further. This study could guide further enhancing the hydrogen-helium separation rate in EHP. It aims to promote the development of hydrogen separation and purification of EHP, making it an efficient method of hydrogen-helium separation instead of palladium membrane. • The basic performance of EHP in hydrogen-helium separation were evaluated. • Proton migration is a speed-controlled step of the EHP process. • EHP is superior to palladium membrane in hydrogen treatment rate and cost. [ABSTRACT FROM AUTHOR]

The prominence of hydrogen energy has brought membrane separation technology to forefront attention. La 2 Ce 2 O 7 , possessing a fluorite structure, exhibits notable stability in both H 2 O and CO 2 , rendering it a prospective material for membrane separation. The impact of Sr doping on the electrochemical characteristics of La 2 Ce 2 O 7 was systematically investigated. The findings indicate that a minor addition of Sr2+ through doping enhances the electrical conductivity, with the most significant improvement observed in La 2-x Sr x Ce 2 O 7-δ (x = 0, 0.05, 0.15, 0.30) when doped by 0.05. Elevated temperature and increased hydrogen partial pressure on the feed side enhance hydrogen permeability. Hydrogen permeation is predominantly governed by bulk diffusion when the membrane thickness exceeds 0.59 mm, while for thicknesses below 0.49 mm, the process is influenced by both surface and bulk diffusion. Moreover, the doped La 2 Ce 2 O 7 exhibit commendable stability in H 2 O and CO 2 environments. Consequently, La 2 Ce 2 O 7 emerges as a promising candidate for ceramic hydrogen separation membranes. • The impact of Sr doping on the electrochemical characteristics of La 2 Ce 2 O 7. • Sr doping increases the oxygen vacancy concentration and conductivity of La 2 Ce 2 O 7. • Pt–La 1.7 Sr 0.3 Ce 2 O 7-δ exhibits the highest hydrogen permeation flux. • The samples are stable at boiling water and CO 2 atmosphere at 900 °C. [ABSTRACT FROM AUTHOR]

Polytetrafluoroethylene (PTFE) capillary membranes, known for the great chemical resistance and thermal stability, are commonly used in membrane separation technologies. However, the strong hydrophobic property of PTFE limits its application in water filtration. This study introduces a method whereby acrylamide (AM), N, N-methylene bisacrylamide (MBA), and vinyltriethoxysilane (VTES) undergo free radical copolymerization, followed by the hydrolysis-condensation of silane bonds, resulting in the formation of hydrophilic three-dimensional networks physically intertwined with the PTFE capillary membranes. The modified PTFE capillary membranes prepared through this method exhibit excellent hydrophilic properties, whose water contact angles are decreased by 24.3–61.2%, and increasing pure water flux from 0 to 1732.7–2666.0 L/m2·h. The enhancement in hydrophilicity of the modified PTFE capillary membranes is attributed to the introduction of hydrophilic groups such as amide bonds and siloxane bonds, along with an increase in surface roughness. Moreover, the modified PTFE capillary membranes exhibit chemical resistance, maintaining the hydrophilicity even after immersion in strong acidic (3 wt% HCl), alkaline (3 wt% NaOH), and oxidative (3 wt% NaClO) solutions for 2 weeks. In conclusion, this promising method yields modified PTFE capillary membranes with great hydrophilicity and chemical resistance, presenting substantial potential for applications in the field of water filtration. [ABSTRACT FROM AUTHOR]

Lysozyme, a common antimicrobial agent, is widely used in the food, biopharmaceutical, chemical, and medicine fields. Rapid and effective isolation of lysozymes is an everlasting topic. In this work, ethylene vinyl alcohol (EVOH) copolymer nanofibrous membranes with a gradient porous structure used for lysozyme adsorption were prepared through layer-by-layer nanofiber wet-laying and a cost-efficient ultraviolet (UV)-assisted graft-modification method, where benzophenone was used as an initiator and 2-acrylamide-2-methylpropanesulfonic acid as a modifying monomer. As indicated in the Fourier Transform Infrared (FTIR) and X-ray photoelectric energy spectrometer (XPS) investigation, sulfonic acid groups were introduced on the surface of the modified nanofibrous membrane, which possessed the ability to adsorb lysozyme. Compared with membranes with homogenous porous structures, membranes with a gradient porous structure present higher static (335 mg/g) and dynamic adsorption capacities (216.3 mg/g). Meanwhile, the adsorption capacity remained high after five cycles of the adsorption–desorption process. The results can be attributed to the gradient porous structure rather than the highest porosity and specific surface area. This suggests that the membrane with comprehensive separation performance can be designed from the view of the transmembrane porous structure, which is of significance for the development of next-generation advanced chromatographic membranes. [ABSTRACT FROM AUTHOR]

As the atmospheric carbon dioxide (CO2) concentration rapidly rises, carbon capture, utilization, and storage (CCUS) is an emerging field for climate change mitigation. Various carbon capture technologies are in development with the help of adsorbents, membranes, solvent-based systems, etc. One of the main challenges in this field is the removal of CO2 from nitrogen (N2) gas. This paper focuses on mixed matrix membrane technology, for which the CO2/N2 separation performance is based on differences in gas permeations. Membrane separation and purification technologies are widely studied for carbon capture. Microporous adsorbents such as zeolites and metal organic frameworks (MOFs) for carbon capture have been attracting researchers' attention due to their highly porous structures, high selectivity values, and tunable porosities. Utilizing microporous adsorbents dispersed within a novel, blended polymer matrix, fourteen membranes were prepared with the commercial MOF ZIF-8, zeolite 13X, and kaolin, with methyl cellulose (MC) and polyvinyl alcohol (PVA), which were tested using a single gas permeation setup in this study. The addition of polyallylamine (PAH) as a chemisorbent was also investigated. These membranes were synthesized both with and without a polyacrylonitrile (PAN) support to compare their performances. MC was found to be an ideal polymeric matrix component to develop free-standing MMMs. At 24 °C and a relatively low feed pressure of 2.36 atm, a free-standing zeolite-13X-based membrane (MC/PAH/13X/PVA) exhibited the highest N2/CO2 selectivity of 2.8, with a very high N2 permeability of 6.9 × 107 Barrer. Upon the optimization of active layer thickness and filler weight percentages, this easily fabricated free-standing MMM made of readily available materials is a promising candidate for CO2 purification through nitrogen removal. [ABSTRACT FROM AUTHOR]

Direct contact membrane distillation tests are carried out on four kinds of dye solutions using the superhydrophobic polyvinylidene difluron-copolymerized hexafluoropropylene nanofiber membrane (PH-E) and its modification coated with polydimethylsiloxane (PDMS) nanoparticles (PDMS-PH-E membrane). The test results show that PDMS-PH-E membrane has higher water flux, and the removal efficiency of four dyes reaches 100%. While the removal efficiency of the PH-E membrane reaches 100% only for two dyes. The loosely absorbed dye structure on PDMS-PH-E membrane roughens the surface, and stimulates the negatively charged droplets to bounce, resulting in an effective anti-fouling and self-cleaning effect and a long-term scaling prevention. [ABSTRACT FROM AUTHOR]

The advent of two-dimensional nanomaterials, a revolutionary class of materials, is marked by their atomic-scale thickness, superior aspect ratios, robust mechanical attributes, and exceptional chemical stability. These materials, producible on a large scale, are emerging as the forefront candidates in the domain of membrane-based gas separation. The concept of defect engineering in 2D nanomaterials has introduced a novel approach in their application for membrane separation, offering an effective technique to augment the performance of these membranes. Nonetheless, the development of customized microstructures in gas separation membranes via defect engineering remains nascent. Hence, this review is designed to serve as a comprehensive guide for the application of defect engineering in 2D nanomaterial-based membranes. It delves into the most recent developments in this field, encompassing the synthesis methodologies of defective 2D nanomaterials and the mechanisms underlying gas transport. Special emphasis is placed on the utilization of defect-engineered 2D nanomaterial-based membranes in gas capture applications. Furthermore, the paper encapsulates the burgeoning challenges and prospective advancements in this area. In essence, defect engineering emerges as a promising avenue for enhancing the efficacy of 2D nanomaterial-based membranes in gas separation, offering significant potential for advancements in membrane-based gas separation technologies. [ABSTRACT FROM AUTHOR]

Improving the microphase separation structure of membranes is considered an effective strategy to solve the trade-off problem, which can increase the conductivity and reduce the swelling. This article designs poly(aryl alkylene) AEMs with different aryl backbone chains (biphenyl, p-terphenyl and m-terphenyl), with the goal of examining the effect of spatial structure main chains on the membrane performance. It is found that the membrane (m-QTPNP) has a better microphase separation structure and a conductivity of 143.5 mS cm−1 (80 °C) via SAXS, TEM and AFM. Due to the lower IEC (2.23 meq g−1), m-QTPNP has a good anti-swelling performance. During tensile testing, the elongation at break of m-QTPNP can reach 105.5% (wet state). Moreover, due to the obvious microphase separation, the attack of OH− on the quaternized groups is reduced, and m-QTPNP has a conductivity retention rate of 95.5% (80 °C, 2 M NaOH, 1560 h). In addition, the peak power density (PPD) of the H 2 /O 2 single cell equipped with m-QTPNP can reach 749 mW cm−2 (80 °C). After 90 h of durability testing, the voltage decayed to 92.2%, with a decay rate of 0.54 mV h−1. • The m-QTPNP AEM shows excellent mechanical properties with elongation at break up to 105.5% in wet state. • The m-QTPNP AEM exhibits an ionic conductivity of 143.5 mS cm−1 at 80 °C. • The peak power density of m-QTPNP in a H 2 /O 2 single cell is 749 mW cm−2. [ABSTRACT FROM AUTHOR]

Membrane separation of aromatics and aliphatics is a crucial requirement in chemical and petroleum industries. However, this task presents a significant challenge due to the lack of membrane materials that can endure harsh solvents, exhibit molecular specificity, and facilitate easy processing. Herein, we present a novel approach to fabricate a covalent triazine framework (CTF) membrane by employing a mix‐monomer strategy. By incorporating a spatial monomer alongside a planar monomer, we were able to subtly modulate both the pore aperture and membrane affinity, enabling preferential permeation of aromatics over aliphatics with molecular weight below 200 Dalton (Da). Consequently, we achieved successful all‐liquid phase separation of aromatic/aliphatic mixtures. Our investigation revealed that the synergistic effects of size sieving and the affinity between the permeating molecules and the membrane played a pivotal role in separating these closely resembling species. Furthermore, the membrane exhibited remarkable robustness under practical operating conditions, including prolonged operation time, various feed compositions, different applied pressure, and multiple feed components. This versatile strategy offers a feasible approach to fabricate membranes with molecule selectivity toward aromatic/aliphatic mixtures, taking a significant step forward in addressing the grand challenge of separating small organic molecules through membrane technology. [ABSTRACT FROM AUTHOR]

Membrane‐based separation has the merit of low carbon footprint. In this study, the pore size of metal–organic framework (MOF) membranes is rationally designed for discriminating various pairs of hydrocarbon isomers. Specifically, Zr‐MOF UiO‐66 (UiO stands for University of Oslo) membranes are developed for separating p/o‐xylene due to their proper pore size. For n‐hexane/2‐methylpentane separation, the functional groups and proportion of the ligands in UiO‐66 are gradually adjusted to effectively regulate the pore size, and UiO‐66‐33Br membranes are constructed. In addition, relying on the utilization of ligands with shorter length, MOF‐801 membranes with smaller pore size are fabricated for n/i‐butane separation. [ABSTRACT FROM AUTHOR]

Membrane separation of aromatics and aliphatics is a crucial requirement in chemical and petroleum industries. However, this task presents a significant challenge due to the lack of membrane materials that can endure harsh solvents, exhibit molecular specificity, and facilitate easy processing. Herein, we present a novel approach to fabricate a covalent triazine framework (CTF) membrane by employing a mix‐monomer strategy. By incorporating a spatial monomer alongside a planar monomer, we were able to subtly modulate both the pore aperture and membrane affinity, enabling preferential permeation of aromatics over aliphatics with molecular weight below 200 Dalton (Da). Consequently, we achieved successful all‐liquid phase separation of aromatic/aliphatic mixtures. Our investigation revealed that the synergistic effects of size sieving and the affinity between the permeating molecules and the membrane played a pivotal role in separating these closely resembling species. Furthermore, the membrane exhibited remarkable robustness under practical operating conditions, including prolonged operation time, various feed compositions, different applied pressure, and multiple feed components. This versatile strategy offers a feasible approach to fabricate membranes with molecule selectivity toward aromatic/aliphatic mixtures, taking a significant step forward in addressing the grand challenge of separating small organic molecules through membrane technology. [ABSTRACT FROM AUTHOR]

Membrane‐based separation has the merit of low carbon footprint. In this study, the pore size of metal–organic framework (MOF) membranes is rationally designed for discriminating various pairs of hydrocarbon isomers. Specifically, Zr‐MOF UiO‐66 (UiO stands for University of Oslo) membranes are developed for separating p/o‐xylene due to their proper pore size. For n‐hexane/2‐methylpentane separation, the functional groups and proportion of the ligands in UiO‐66 are gradually adjusted to effectively regulate the pore size, and UiO‐66‐33Br membranes are constructed. In addition, relying on the utilization of ligands with shorter length, MOF‐801 membranes with smaller pore size are fabricated for n/i‐butane separation. [ABSTRACT FROM AUTHOR]

Building construction requires important amounts of freshwater, thus depleting the already stressed natural water resources. This issue could be addressed by using recycled water in construction and in building systems. However, integrating greywater recycling systems is limited by complexity, costs, vulnerability to environmental fluctuations, and coordination of policymakers, developers, and construction practitioners. Here, we review recycled water systems in buildings with focus on case studies of successful implementations, policies, recycled water treatment in buildings, and health aspects. Compared to conventional tap water, the incorporation of recycled water enhances the consistency and workability of reclaimed water concrete by 12–14%, and it increases concrete viscosity by 11% and yield stress by 25%. We discuss the intricacies of building water recycling systems, with emphasizing on conserving water, mitigating environmental impact, and enhancing economic efficiency. Challenges include water quality assurance, dual piping infrastructure, and regulatory compliance. Government interventions, including incentives, mandates, and subsidy policies, emerge as drivers for widespread adoption. Technological advancements, such as membrane filtration and advanced oxidation processes, are examined for strengths and limitations. [ABSTRACT FROM AUTHOR]

In the present study, flat cellulose acetate ultrafiltration membranes were prepared first by nonsolvent induced phase separation method. Then chiral membranes for separating the enantiomers were prepared by grafting the ultrafiltration membranes using ethylenediamine‐β‐cyclodextrin as the chiral selector and epichlorohydrin as the spacer arm. The pure water permeability of the ultrafiltration membrane was around 115 L·m−2·h−1·bar−1. The properties of the chiral membranes were characterized using infrared spectroscopy (ATR‐FTIR), X‐ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The chiral membrane performance in enantiomer separation was evaluated with racemates, such as mandelic acid (MA), 2‐chloromandelic acid (2‐ClMA), 4‐chloromandelic acid (4‐ClMA), and methyl mandelate (MM). The influence of feed concentration on the separation efficiency was also investigated. The results indicated that the enantiomeric excess percentages (e.e%) of the racemic mixtures for these four chiral compounds were up to 31.8%, 25.4%, 17.8%, and 32.6%, respectively. The binding free energy of the chiral selector with the (S)‐enantiomer calculated by molecular dynamics simulations was stronger than that with the (R)‐enantiomer, which was consistent with the experimental results (higher concentration of (R)‐enantiomer in the permeate). This supports the affinity absorption‐separation mechanism. [ABSTRACT FROM AUTHOR]

In the cheese industry, whey, which is rich in lactose and proteins, is underutilized, causing adverse environmental impacts. The fractionation of its components, typically carried out through filtration membranes, faces operational challenges such as membrane fouling, significant protein loss during the process, and extended operating times. These challenges require attention and specific methods for optimization and to increase efficiency. A promising strategy to enhance industry efficiency and sustainability is the use of enzymatic pre‐treatment with the enzyme transglutaminase (TGase). This enzyme plays a crucial role in protein modification, catalyzing covalent cross‐links between lysine and glutamine residues, increasing the molecular weight of proteins, facilitating their retention on membranes, and contributing to the improvement of the quality of the final products. The aim of this study is to review the application of the enzyme TGase as a pretreatment in whey protein filtration. The scope involves assessing the enzyme's impact on whey protein properties and its relationship with process performance. It also aims to identify both the optimization of operational parameters and the enhancement of product characteristics. This study demonstrates that the application of TGase leads to improved performance in protein concentration, lactose permeation, and permeate flux rate during the filtration process. It also has the capacity to enhance protein solubility, viscosity, thermal stability, and protein gelation in whey. In this context, it is relevant for enhancing the characteristics of whey, thereby contributing to the production of higher quality final products in the food industry. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Produced water (PW) presents a significant challenge as a complex wastewater stream, necessitating thorough treatment prior to disposal or further reuse. This study is dedicated to the assessment, reproduction and upgrading of literature‐based preparation protocols for synthetic PW at the tertiary treatment stage; more specifically those methods utilizing high‐pressure homogenizers and ultrasonication. The objective was to produce synthetic model water that can be employed as a standardized controllable medium for optimization experiments of PW treatment techniques. This synthetic medium should facilitate the investigation of specific challenges associated with PW tertiary treatment, independent of the different and often unpredictable composition of real PW. The refined methods were modified for the application in lab‐scale research investigating the use of membrane filtration as tertiary treatment step. [ABSTRACT FROM AUTHOR]