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Carbon nanotubes (CNTs) have potential applications in separation membranes and nanofluidic devices. It is well known that the behavior of water molecules confined in CNTs is affected by surface functional groups and external electric fields, leading to structural changes. The understanding of these structural changes of water within various CNTs is crucial, particularly in the context of material separation. While there have been many investigations into the effects of individual specific functional groups, a comprehensive understanding of the effect of these functional groups and the electric fields they generate on water molecules remains elusive. In this study, we investigate the properties of water molecules in tip-charged CNTs of (8,8), (10,10), and (12,12) chiral vectors with positive charges at one tip and negative charges at the other tip. Abstraction of ionized functional groups as tip charges enables a comprehensive understanding that is independent of individual functional groups. The symmetrically arranged tip-charges spontaneously generate a strong and symmetric electric field in the CNTs. However, the strength and directionality of the electric field are non-uniform and complex. In the interiors of (8,8) and (10,10) tip-charged CNTs, helical and square structures, which have disturbances caused by the non-uniformity of the electric field, are observed. The properties of the water molecules differed significantly in the center of the CNTs and near positive and negative charges, despite the electric field symmetry. In (12,12) tip-charged CNTs with 12 charges, a local ring structure is observed in the vicinity of negative charges but not in the vicinity of positive charges. It is concluded that the water structures in tip-charged CNTs have different characteristics from those in plain CNTs under a uniform electric field. [ABSTRACT FROM AUTHOR]

Inspired by biological channels, achieving precise separation of ion/water and ion/ion requires finely tuned pore sizes at molecular dimensions and deliberate exposure of charged groups. Covalent organic frameworks (COFs), a class of porous crystalline materials, offer well-defined nanoscale pores and diverse structures, making them excellent candidates for nanofluidic channels that facilitate ion and water transport. In this study, we perform molecular simulations to investigate the structure and kinetics of water and ions confined within the typical COFs with varied exposure of charged groups. The COFs exhibit vertically arrayed nanochannels, enabling diffusion coefficients of water molecules within COFs to remain within the same order of magnitude as in the bulk. The motion of water molecules manifests in two distinct modes, creating a mobile hydration layer around acid groups. The ion diffusion within COFs displays a notable disparity between monovalent (M+) and divalent (M2+) cations. As a result, the selectivity of M+/M2+ can exceed 100, while differentiation among M+ is less pronounced. In addition, our simulations indicate a high rejection (R > 98%) in COFs, indicating their potential as ideal materials for desalination. The chemical flexibility of COFs indicates that would hold significant promise as candidates for advanced artificial ion channels and separation membranes. [ABSTRACT FROM AUTHOR]

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]

Covalent organic framework (COF) membranes feature with well‐developed 1D in‐plane pores and parallelly arranged 2D interlayer gallery, presenting promising platform for precise separations. However, it remains a formidable challenge to construct and regulate membrane channels at angstrom scale. Herein, pH‐sensitive dopamine is taken advantage to elaborately engineer the spatial size of 1D/2D channels in COF membranes for the separations of alkali metal ions. Acid treatment allows monomolecular dopamine to segment 1D in‐plane pores of COF membrane, achieving ultramicroporous regulation from 1.25 nm to 0.71 nm, which enables high selectivity of 18.7 for K+/Li+ separation. Molecular dynamics simulations reveal the higher dehydration degree, weaker channel‐cation interaction and faster diffusion coefficient of K+ than Li+. For alkaline treatment, dopamine self‐polymerizes to form nanoparticles between COF layers, which enlarges the 2D interlayer channels from 0.33 nm to 0.45 nm in COF membrane, enabling high‐permeance ion/molecule separations. The water permeance increases 86.7% to 404 L m−2 h−1 bar−1, without the sacrifice of membrane sieving ability. Both cation separation and ion/molecule separation performances outperform the current state‐of‐the‐art membranes. This dopamine‐mediated channel engineering strategy may provide the new insights for the design of membrane channels in precise separations. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) are prized for their selective dissolution of carbon dioxide (CO2), leading to their widespread use in ionogel membranes for gas separation. Despite their advantages, creating sustainable ionogel membranes with high IL contents poses challenges due to limited mechanical strength, leakage risks, and poor recyclability. Herein, we leverage copolymerized and supramolecularly bound ILs to develop ionogel membranes with high mechanical strength, zero leakage, and excellent self‐healing and recycling capabilities. These membranes exhibit superior ideal selectivity for gas separation compared to other reported ionogel membranes, achieving a CO2/nitrogen selectivity of 61.7 and a CO2/methane selectivity of 24.6, coupled with an acceptable CO2 permeability of 186.4 Barrer. Additionally, these gas separation ionogel membranes can be upcycled into ionic skins for sensing applications, further enhancing their utility. This research outlines a strategic approach to molecularly engineer ionogel membranes, offering a promising pathway for developing sustainable, high‐performance materials for advanced gas separation technologies. [ABSTRACT FROM AUTHOR]

Bioinspired superwetting oil–water separation strategies have received significant attention for their potential in addressing global water scarcity and aquatic pollution challenges. Over the past two decades, the field has rapidly developed, reaching a pivotal phase of innovation in the oil–water separation process. However, many groundbreaking studies have not received extensive scientific recognition. In this review, we systematically examine the application of bioinspired superwetting materials for complex multiscale oil–water separation. We discuss the development of 2D membrane filtration and 3D sponge adsorption materials in confined spaces, summarizing the core separation mechanisms, key research findings, and the evolutionary logic of these materials. Additionally, we highlight emerging open-space separation strategies, emphasizing several novel dynamic separation devices of significant importance. We evaluate and compare the design concepts, separation principles, materials used, comprehensive performance, and existing challenges of these diverse strategies. Finally, we summarize these advantages, critical bottlenecks, and prospects of this field and propose potential solutions for real oil–water separation processes from a general perspective. [ABSTRACT FROM AUTHOR]

The growing scarcity of clean water necessitates urgent interventions in wastewater treatment. Polymeric membranes are prevalent in this domain. However, due to their hydrophobic behaviour, they become more prone to fouling. To address this issue, we synthesized hydrophilic nanomaterials as additives to prepare polymer nanocomposite membranes with enhanced hydrophilicity. The eco-friendly zinc oxide (ZnO) nanomaterial was synthesized via a green route, and reduced graphene oxide (rGO) and a rGO/ZnO composite were synthesized using a chemical process and characterized using FESEM, FTIR, XRD, and zeta potential techniques. The synthesized nanomaterials were incorporated into PVDF membranes, and the prepared membranes were characterized using FESEM with EDX, FTIR, and contact angle measurements, along with mechanical strength determination. The filtration properties of the membranes were evaluated using a dead-end filtration module. The FESEM images revealed the finger-like structure in the membranes, which increases with the incorporation of nanomaterials. The results demonstrated that among all the membranes, the rGO/ZnO-PVDF showed the highest membrane permeability due to increased membrane porosity, pore size, and finger-like macrovoid sponge structures. The rejection of BSA protein and CBB dye increased due to the negative charge provided by the ZnO in the rGO/ZnO nanocomposite. The antifouling study reveals that the rGO/ZnO-PVDF membrane had the highest FRR value of ∼50.05% among the various synthesized membranes. The disk diffusion data of the synthesized nanomaterials and nanocomposite membranes confirms their antibacterial activity and suggests that the addition of rGO/ZnO nanomaterial can provide anti-biofouling behaviour to the polymer membranes by minimizing the adhesion of bacteria on the surface of the membrane. The results showed that the rGO/ZnO-PVDF membrane possesses antifouling and anti-biofouling behaviour, useful for minimising the pollutants from wastewater. [ABSTRACT FROM AUTHOR]

This study aims to assess the efficacy of machine learning models in predicting solute concentration (C) distribution in a membrane separation process, using the input parameters which are spatial coordinates. Computational fluid dynamics (CFD) was employed with machine learning for simulation of process. The models evaluated include Kernel Ridge Regression (KRR), Radius nearest neighbor regression (RNN), K-nearest neighbors (KNN), LASSO, and Multi-Layer Perceptron (MLP). Additionally, Harris Hawks Optimization (HHO) was utilized to fine-tune the hyperparameters of these models. Leading the way is the MLP model, which achieves a remarkable test R2 value of 0.98637 together with very low RMSE and MAE values. Strongness and generalization capacity are shown by its consistent performance on test and training datasets. To conclude, the effectiveness of using machine learning regression methods more especially, KRR, KNN, RNN, LASSO, and MLP in estimating concentration from spatial coordinates was demonstrated in this work. For separation science via membranes where predictive modeling of spatial data is essential, the results offer important new perspectives by developing hybrid model. [ABSTRACT FROM AUTHOR]

Artificial membranes with ion‐selective nanochannels for high‐efficiency mono/divalent ion separation are of great significance in water desalination and lithium‐ion extraction, but they remain a great challenge due to the slight physicochemical property differences of various ions. Here, the successful synthesis of two‐dimensional TpEBr‐based covalent organic framework (COF) nanosheets, and the stacking of them as consecutive membranes for efficient mono/divalent ion separation is reported. The obtained COF nanosheet membranes with intrinsic one‐dimensional pores and abundant cationic sites display high permeation rates for monovalent cations (K+, Na+, Li+) of ≈0.1–0.3 mol m−2 h−1, while the value of divalent cations (Ca2+, Mg2+) is two orders of magnitude lower, resulting in an ultrahigh mono/divalent cation separation selectivity up to 130.4, superior to the state‐of‐the‐art ion sieving membranes. Molecular dynamics simulations further confirm that electrostatic interaction controls the confined transport of cations through the cationic COF nanopores, where multivalent cations face i) strong electrostatic repulsion and ii) steric transport hindrance since the large hydrated divalent cations are retarded due to a layer of strongly adsorbed chloride ions at the pore wall, while smaller monovalent cations can swiftly permeate through the nanopores. [ABSTRACT FROM AUTHOR]

This review examines recent technological developments for recovering critical metals from mining and metallurgical waste streams, focusing on Co, Ga, Ge, In, Li, Ni, Re, Te, Sn, W, and V. Novel approaches using electrochemical methods, membranes, solvent extraction, and biomining are critically evaluated for their effectiveness and potential for industrial adoption. Key competitive advantages of these technologies are discussed, along with aspects requiring further research, such as process control, fouling issues, and microbial stability. The exploration of integrated and hybrid solutions combining different technologies is a potential game-changer for technology transfer. Finally, while these novel approaches show promise, further research is needed to overcome challenges related to cost, process control, and scalability. Addressing these issues is crucial for successfully transitioning these technologies from laboratory-scale experiments to industrial applications. By overcoming these hurdles, the mining and metallurgy sector can play a vital role in supplying critical metals for the zero-carbon transition while reducing its environmental impact and advancing toward a circular economy. [ABSTRACT FROM AUTHOR]

We introduce a "solution‐processing‐transformation" strategy, deploying solvent vapor as scaffolds, to fabricate high‐quality hydrogen‐bonded organic framework (HOF) membranes. This strategy can overcome the mismatch in processing conditions and crystal growth thermodynamics faced during the facile solution processing of the membrane. The procedure includes the vapor‐trigged in situ transformation of dense amorphous supramolecules to crystalline HOF‐16, with HOF‐11 as the transient state. The mechanism involves a vapor‐activated dissolution‐precipitation equilibrium shifting and hydrogen bonding‐guided molecule rearrangement, elucidated through combined experimental and theoretical analysis. Upon removal of the molecular scaffolds, the resulting HOF‐16 membranes showcase significant improvement in hydrogen separation performance over their amorphous counterparts and previously reported HOF membranes. The method's broad applicability is evidenced by successfully extending it to other substrates and HOF structures. This study provides a fundamental understanding of guest‐induced ordered supramolecular assembly and paves the way for the advanced manufacture of high‐performance HOF membranes for gas separation processes. [ABSTRACT FROM AUTHOR]

Achieving precise selective separation of monovalent and divalent cations, as well as anions, is vital yet challenging in practical applications involving complex component treatments. Current membranes are typically effective for separating either cation pairs or anion pairs. To address this issue, a straightforward strategy for fabricating a nanofiltration (NF) membrane is developed that selectively permeates monovalent ions. This study focused on neutralizing the surface charge and tuning the pore size distribution of the polyamide membranes through a secondary interfacial polymerization using a zwitterionic copolymer consisting of 2‐methacryloyloxyethyl phosphorylcholine and 2‐aminoethyl methacrylate hydrochloride. The optimized NF membrane prepared in this study, with a near‐neutrally charged membrane surface and appropriate pore size distribution, demonstrates favorable performance in precisely separating monovalent and divalent ions, irrespective of the ion charge sign. The optimum NF membrane features high selectivity for both Cl−/SO42− (93) and Li+/Mg2+ (67) ion pairs, along with high water permeance of 8.5 L m−2 h−1 bar−1, making it competitive with many reported membranes. This study offers new insights into the ion‐selective mechanisms of polyamide membranes for monovalent/divalent ions and may guide the development of advanced membranes with single‐solute selectivity. [ABSTRACT FROM AUTHOR]

Metal–organic frame UiO‐66‐NH2 was modified by 3‐glycidyl ether oxypropyl trimethoxysilane (KH560), and KH560‐UiO‐66‐NH2 was synthetized and added to Pebax to prepare KH560‐UiO‐66‐NH2/Pebax mixed matrix membranes (MMMs). The epoxy group of KH560 had an amine‐epoxidation reaction with the NH2 in UiO‐66‐NH2, which prevented UiO‐66‐NH2 from agglutinating in the MMMs. In addition, the NH bond and OH bond of KH560‐UiO‐66‐NH2 could theoretically form hydrogen bonds with CO and NH bonds in the main chain of polymerization, respectively, so as to improve the interfacial compatibility between fillers and polymers. The structure and properties of the filler particles and MMMs were evaluated by Fourier transform infrared spectrometer, x‐ray diffraction, scanning electron microscopy, and thermogravimetric analyzer. The results showed that the filler particles were successfully synthesized, and had good crystallinity, uniform size distribution, and good thermal stability. The inorganic and organic interfaces of MMMs had no obvious interface defects. The obtained KH560‐UiO‐66‐NH2/Pebax MMMs showed CO2 permeability of 111.52 Barre and CO2/N2 selectivity of 92.16, which were 85.65% and 88.73% higher than that of pristine membranes, respectively. The gas separation performance of MMMs was significantly improved, exceeding the upper bound of 2008 Robeson. [ABSTRACT FROM AUTHOR]

In specific applications like ice-repellent coatings or membrane separation technology, wettability is a key parameter affecting the applicability of commodity polymers. This study presents a technique to fine-control the wetting properties of a hierarchically structured polypropylene surface, enabling the transition between superhydrophobic and superhydrophilic states. To demonstrate the tunability of the wetting properties of polypropylene (PP) substrate, we prepared in a consecutive way superhydrophobic (advancing contact angle (CAadv) of 152°) and superhydrophilic (CAadv of 0°) material by solvent-treatment and mild air plasma treatment. The optimal plasma treatment parameters to achieve superhydrophilic wetting behaviour, which is stable for at least one week of storage in air was also explored. Water contact angle measurement and X-ray photoelectron spectroscopy were used to monitor the time dependency of hydrophobic recovery on a hierarchically structured PP surface. With a simple model considering structural and wetting parameters, we characterized the droplet spreading behaviour of plasma-treated roughened surfaces, which exhibited superhydrophilic wetting behaviour with equilibrium CAadv of nearly 0°. The proposed model, which aligns well with experimental data, can be used to compare the droplet spreading behaviour of plasma-treated roughened surfaces. [ABSTRACT FROM AUTHOR]

CALF-20, [Zn2(1,2,4-triazolate)2(oxalate)] shows remarkable performance in post-combustion carbon capture, even under humid conditions1 but its reported crystal morphology hinders its applicability in mixed matrix membranes (MMMs). Here, a route to its preparation as platelets a few tens of nm thick is reported. These were incorporated into a PEBAX MH1567 polymer matrix and the resultant MMMs display improvement in CO2 permeability and CO2/N2 selectivity. [ABSTRACT FROM AUTHOR]

Osmotic energy conversion based on reverse electrodialysis (RED) technology has attracted intense attention. As the key component, the ion‐selective membranes should meet the basic requirements of high power density, high mechanical strength, and easy preparation. Polyelectrolyte hydrogel materials are good candidates, due to their high charge density. However, the severe swelling effect decreases the ion selectivity and mechanical strength. To solve this problem, an anti‐swelling 3D nanohydrogel is demonstrated, which is in situ polymerized in the nanoporous polyimide (PI) membrane, exhibiting ultrahigh power density in osmotic energy conversion. Because of the nano‐confinement of the PI matrix, the swelling ratio of the nanohydrogel decreases to 37.5% from 593.2% of the bulk hydrogel. Meanwhile, the hybrid membrane exhibits excellent mechanical strength (≈89.5 MPa). Under a 500‐fold concentration gradient, the nanohydrogel generates a power density of up to 48.5 W m−2, one order of magnitude higher than that of the bulk hydrogel. The anti‐swelling 3D nanohydrogel introduces a new concept in designing separation membranes for osmotic energy conversion. [ABSTRACT FROM AUTHOR]

Nanoporous membranes have a variety of applications, one of which is the size‐selective separation of nanoparticles. In drug delivery, nanoporous membranes are becoming increasingly important for the isolation of exosomes, which are bio‐nanoparticles. However, the low pore density and thickness of commercial membranes limit their efficiency. There have been many attempts to fabricate sub‐micrometer thin membranes, but the limited surface area has restricted their practicality. In this study, large‐area silicon nitride nanosieves for enhanced diffusion‐based isolation of exosomes are presented. Notably, these nanosieves are scaled to sizes of up to 4‐inch‐wafers, a significant achievement in overcoming the fabrication challenges associated with such expansive areas. The method employs a 200 nm porous sieve (38.2% porosity) for exosome separation and a 50 nm sieve (10.7% porosity) for soluble protein removal. These 300 nm thick nanosieves outperform conventional polycarbonate membranes by being 50 times thinner, thereby increasing nanoparticle permeability. The method enables a 90% recovery rate of intact exosomes from human serum and a purity ratio of 3 × 107 particles/µg protein, 4.6 times higher than ultracentrifugation methods. The throughput of the method is up to 15 mL by increasing the size of the nanosieve, making it an ideal solution for large‐scale exosome production for therapeutic purposes. [ABSTRACT FROM AUTHOR]

A wax-patterned paper analytical device (µPAD) has been developed for point-of-care colourimetric testing of serum glutamic oxaloacetic transaminase (SGOT). The detection method was based on the transamination reaction of aspartate with α-ketoglutarate, leading to the formation of oxaloacetate which reacts with the reagent Fast Blue BB salt and forms a cavern pink colour. The intensity of the cavern pink colour grows as the concentration of SGOT increases. UV–visible spectroscopy was utilized to optimize reaction conditions, and the optimized reagents were dropped onto the wax-patterned paper. The coloured PADs, after the addition of SGOT, have been photographed, and a colour band has been generated to correlate the SGOT concentration visually. The images were used to calculate the intensity values using ImageJ software, which inturn was used to calculate the SGOT concentration. The PADs were also tested with serum samples, and SGOT spiked serum samples. The PAD could detect the SGOT concentration ranging from 5 to 200 U/L. The analysis yielded highly accurate results with less than 6% relative error compared to the clinical sample. This colourimetric test demonstrated exceptional selectivity in the presence of other biomolecules in the blood serum, with a detection limit of 2.77 U/L and a limit of quantification of 9.25 U/L. Additionally, a plasma separation membrane was integrated with the PAD to directly test SGOT from finger-prick blood samples. [ABSTRACT FROM AUTHOR]

The global energy market is shifting toward renewable, sustainable, and low-carbon hydrogen energy due to global environmental issues, such as rising carbon dioxide emissions, climate change, and global warming. Currently, a majority of hydrogen demands are achieved by steam methane reforming and other conventional processes, which, again, are very carbon-intensive methods, and the hydrogen produced by them needs to be purified prior to their application. Hence, researchers are continuously endeavoring to develop sustainable and efficient methods for hydrogen generation and purification. Membrane-based gas-separation technologies were proven to be more efficient than conventional technologies. This review explores the transition from conventional separation techniques, such as pressure swing adsorption and cryogenic distillation, to advanced membrane-based technologies with high selectivity and efficiency for hydrogen purification. Major emphasis is placed on various membrane materials and their corresponding membrane performance. First, we discuss various metal membranes, including dense, alloyed, and amorphous metal membranes, which exhibit high hydrogen solubility and selectivity. Further, various inorganic membranes, such as zeolites, silica, and CMSMs, are also discussed. Major emphasis is placed on the development of polymeric materials and membranes for the selective separation of hydrogen from CH4, CO2, and N2. In addition, cutting-edge mixed-matrix membranes are also delineated, which involve the incorporation of inorganic fillers to improve performance. This review provides a comprehensive overview of advancements in gas-separation membranes and membrane materials in terms of hydrogen selectivity, permeability, and durability in practical applications. By analyzing various conventional and advanced technologies, this review provides a comprehensive material perspective on hydrogen separation membranes, thereby endorsing hydrogen energy for a sustainable future. [ABSTRACT FROM AUTHOR]

The room temperature ionic liquid trihexyl(tetradecyl)phosphonium decanoate ([P66614][Dec]) was employed in the liquid-liquid extraction of Co(II) from hydrochloric acid solutions in the presence of Ni(II). The extraction performance in liquid-liquid separations showed a strong dependence on the acid content of the feed aqueous solution. The best performance in terms of extracted cobalt and selectivity was obtained when the feed contained a HCl concentration above 6 M On the contrary, when the experiment was performed in absence of HCl, a lower extraction and Co/Ni selectivity were obtained. This behavior has been rationalized by considering the protonation of the [Dec]− anion and the different Co(II)/Ni(II) speciation in HCl media. Moreover, polymer inclusion membranes (PIMs) were prepared using PVC and [P66614][Dec] at different weight rations. Only the PIM formulated with a 30:70/PVC:[P66614][Dec] weight ratio demonstrated effective extraction of Co(II) from the HCl solution. The extraction efficiency and selectivity of the PIM was comparable to that from biphasic liquid experiments at 8 M HCl. The results of this study constitute a promising background for further practical developments of carboxylate-based ILs applied in Co/Ni separations. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) membranes have garnered significant attention in the field of membrane separation due to their superb hydrophilicity, abundant functional groups, extensive surface area, and chemical stability. In this study, we have established a simple and effective method to enhance GO layered materials using nitrogen-doped carbon dots (N–CDs) molecules as inserts and surface modifiers, aiming to develop highly efficient GO-based membranes. Consequently, the incorporation of N–CDs into the two-dimensional GO membrane augments its hydrophilicity and increases the membrane interlayer distance. Under ultra-low pressure nanofiltration conditions, the optimum GN-12 composite membrane exhibited a remarkable average pure water flux of 6.06 L m−2 h−1 bar−1. This flux was approximately 19.5 times higher than that of the pure GO membrane, which had a flux of 0.31 L m−2 h−1 bar−1. Furthermore, the composite membrane exhibited excellent capability in intercepting several charged dye molecules, with an interception rate exceeding 99.6%. Furthermore, the optimized composite membrane demonstrated robust performance and structural stability even under varying pH conditions. The findings of this fundamental research provide a straightforward and cost-effective strategy for the production of high-performance two-dimensional based nanofiltration membranes. [ABSTRACT FROM AUTHOR]

This study investigates simulation of pharmaceutical separation via membrane distillation process by computational simulation and machine learning modeling strategy. The efficacy of three regression models, i.e., Multi-layer Perceptron (MLP), Gamma Regression, and Support Vector Regression (SVR) in predicting the solute concentration, C(mol/m³), was evaluated. The hyper-parameters were optimized by fine-tuning the models using the Red Deer Algorithm (RDA). Computational analyses were carried out for removal of pharmaceuticals from solution by membrane distillation in continuous mode. Mass transfer and machine learning models were implemented focusing on concentration of solute in the feed section of membrane. Results indicate that the Multi-layer Perceptron model achieved great accuracy with an R2 of 0.9955, an MAE of 0.0084, and an RMSE of 0.0148, effectively capturing complex nonlinear relationships in the data. Gamma Regression also performed acceptably, with fitting R2 of 0.9214, showing its suitability for positively skewed data. The Support Vector Regression model, while capturing the general trend, showed the lowest performance with an R2 of 0.8710. These findings suggest that the Multi-layer Perceptron is the most accurate model for this dataset, followed by Gamma Regression and Support Vector Regression. This underscores the importance of careful model selection and optimization in regression analysis in combination with computational simulation of membrane processes. [ABSTRACT FROM AUTHOR]

Traditional Chinese medicine (TCM) is often composed of a variety of natural medicines. Its composition is complex, and many of its components can not be analyzed and identified. The first step in the rational application of TCM is to successfully separate the effective components which is also a great inspiration for the development of new drugs. Among the many separation technologies of TCM, the traditional heating concentration separation technology has high energy consumption and low efficiency. As a new separation technology, membrane separation technology has the characteristics of simple operation, high efficiency, environment-friendly and so on. The separation effect of high molecular weight difference solution is better. The applications of several main membrane separation technologies such as microfiltration, nanofiltration, ultrafiltration and reverse osmosis are reviewed, the methods of restoring membrane flux after membrane fouling are discussed, and their large-scale industrial applications in the future are prospected and summarized. [ABSTRACT FROM AUTHOR]

Carbon capture technologies are imperative for addressing climate change objectives. Among the available solutions, five post-combustion capture technologies stand out for their efficacy in trapping CO2 from flue gas emissions: chemical absorption, adsorption, membrane separation, cryogenic distillation, and electrochemical processes. Their implementation spans both laboratory investigations and pilot/commercial applications. This review systematically examines these five CO2 capture technologies, emphasizing their progression in industrial applications. Current research endeavors are explored, and pivotal challenges are underscored. When addressed, they can enhance both performance and economic feasibility. Comparative analyses indicate that while adsorption, membrane, and cryogenic processes have seen pilot/commercial applications, chemical absorption is the most cost-effective and established method, accounting for an operational capacity of approximately 50 million tons of CO2 annually. Remarkably, electrochemical devices have exhibited superior performance at the laboratory scale, achieving CO2 removal efficiencies exceeding 98% with a simple activation mechanism. Comprehensive strategies addressing operational costs and device configurations are essential to transition this technology to larger scales. [ABSTRACT FROM AUTHOR]

With the increase in air pollutants and bacteria hazards, conventional melt-blown cloth of polypropylene (PP), which is widely used as the filtering medium, can no longer meet people's needs due to its insufficient filtration efficiency, lack of antibacterial function, etc. In this study, the nanoparticles of the zinc and cobalt imidazolate framework (ZnCo-ZIF) were synthesized and directly incorporated into polylactide (PLA) to prepare PLA/ZnCo-ZIF fibrous membranes through electrospinning methodology. The addition of ZnCo-ZIF resulted in a decrease in the average diameter of fiber from 1.01 μm of pure PLA membrane to 0.72 μm of PLA/ZnCo-ZIF (3 wt%) membrane. The PM filtration and antimicrobial properties of PLA/ZnCo-ZIF fibrous membranes were tested. The PLA/ZnCo-ZIF (2 wt%) membrane displayed great filtration ability, and the filtration efficiencies for PM2.5 and PM10 were 90.88% and 93.00%, compared to 75.76% and 79.37% of PP melt-blown cloth. In addition, the antibacterial rates of the PLA/ZnCo-ZIF (3 wt%) membrane reached 100% and 93.24% against E. coli and S. aureus, which were higher than 85.80% and 90.59% of the PLA/ZIF-8 (3 wt%) membrane. The prepared membranes could be used in the field of masks instead of PP melt-blown fabric, and they solved the problem of the non-degradability and non-functionalization of melt-blown fabric. [ABSTRACT FROM AUTHOR]

The recent discovery of nanoplastics in most ecosystems is a major, yet poorly known health issue. Here, we review nanoplastics with focus on their presence in the environment, their methods of detection, and their impact on the nitrogen cycle. Nanoplastics are widely distributed in ecosystems; however, their real concentrations are not known due to the limitation of actual detection methods. Detection methods include techniques based on mass spectrometry, optical instruments, and total organic carbon. Total organic carbon-based methods involve first membrane filtration and oxidation as pretreatment, then the measurement of total organic carbon as the total concentration of nanoplastics. Total organic carbon-based methods are easy and cost-effective, compared with other methods. Nanoplastics negatively impact ecosystems and nitrogen removal. Nanoplastics can adsorb on microbial cell membranes then disrupt the membrane integrity. Nanoplastics can also induce oxidative stress. Nitrogen cycling is substantially inhibited by nanoplastics during laboratory tests. [ABSTRACT FROM AUTHOR]

The effect of carbonization temperature on thin-film carbon membranes prepared by carbonization of sorbitol and intended for pervaporation desalination was investigated. Thermal properties, functional groups, phase structures, and surface morphology of the prepared carbon and membrane materials were studied by thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy, x-ray diffraction and scanning electron microscope, respectively, while the membrane performance was evaluated in the pervaporation process. At 400 °C, the TGA revealed a drastic decrease in the sorbitol mass, which correlated with the loss of hydroxyl groups, leaving C–C and C=C groups as carbon materials. Regardless of the applied carbonization temperature, all carbon materials have an amorphous phase; carbonization temperature affects the surface morphology of the carbon membrane, both surface contours and layer thickness, which is directly proportional to desalination performance. The membrane performance was investigated using 1 wt.%, 3.5%, and 7% NaCl solutions at different feed temperatures. Higher carbonization temperatures produce membranes with superior separation performance. The sorbitol-derived carbon membrane carbonized at 350 °C with a concentration of 3.5% and feed solution temperature of 60 °C yielded the best desalination performance, where salt rejection was > 99.9% and water flux was 17.35 kg m−2 h−1. The carbon membrane exhibited excellent salt rejection, close to 100%. It can maintain the separation performance for up to 100 working hours, indicating that the carbon membrane from the sorbitol precursor has the potential to be utilized as a long-term pervaporating membrane. [ABSTRACT FROM AUTHOR]

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Spirulina (Arthospira platensis) is known for its rich content of natural compounds like phycocyanin, chlorophylls, carotenoids, and high protein levels, making it a nutrient-dense food. Over the past decade, research has aimed to optimize the extraction, separation, and purification of these valuable metabolites, focusing on technologies such as high-pressure processing, ultrasound-assisted extraction, and microwave-assisted extraction as well as enzymatic treatments, chromatographic precipitation, and membrane separation. In this study, various extraction methods (conventional vs. ultrasound-assisted), solvents (water vs. phosphate buffer), solvent-to-biomass ratios (1:5 vs. 1:10), and ultrafiltration (PES membrane of MWCO 3 kDa, 2 bar) were evaluated. The quantities of total protein, phycocyanin (PC), chlorophyll a (Cla), and total carotenoids (TCC) were measured. The results showed that ultrasound-assisted extraction (UAE) with phosphate buffer at a 1:10 ratio yielded a metabolite-rich retentate (MRR) with 37.0 ± 1.9 mg/g of PC, 617 ± 15 mg/g of protein, 0.4 ± 0.2 mg/g of Cla, and 0.15 ± 0.14 mg/g of TCC. Water extraction in the concentration process achieved the highest concentrations in MRR, with approximately 76% PC, 92% total protein, 62% Cla, and 41% TCC. These findings highlight the effective extraction and concentration processes to obtain a metabolite-rich retentate from Spirulina biomass, reducing the volume tenfold and showing potential as a functional ingredient for the food, cosmetic, and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Featured Application: Slaughterhouse wastewater recycling using a combined process consisting of flotation, membrane bioreactor, and reverse osmosis. The implementation of research results in industrial applications is a crucial step in the development of innovative technologies. In this work, slaughterhouse wastewater recycling was successfully realized. The system, comprising a process combination of flotation, membrane bioreactor, and reverse osmosis, was able to treat the wastewater from a medium-sized poultry slaughterhouse in northwestern Tunisia. The process managed to treat approximately one-third of the wastewater to the required standard for agricultural irrigation. An additional 35% was purified to drinking-water quality. The remaining water was discharged as concentrate, meeting the necessary limits for indirect discharge. As a result, the slaughterhouse's fresh water consumption was reduced by 35% and the amount of wastewater by around 70%. With the combined system, average reductions of 99%, 98%, and 96% were achieved for the parameters COD, TN, and electrical conductivity, respectively. [ABSTRACT FROM AUTHOR]

Nanofiltration (NF) has become a widely used technology in water treatment due to its environmental friendliness, energy efficiency, cost-effectiveness, and operational simplicity. However, polyamide (PA) NF membranes still face challenges, including low permeate flux, limited resistance to organic pollutants, and inadequate resilience to residual chlorine. To address these issues, this study developed a thin-film composite (TFC) NF membrane featuring a separation layer of sandwich structure. Initially, a single separation layer of polyvinyl alcohol (PVA) NF membrane was prepared, followed by the fabrication of a PA layer on its surface, and ultimately, a second PVA layer was constructed on the PA layer. The experimental results show that the PVA/PA/PVA sandwich structure TFC exhibits high permeability to pure water and robust resistance to both pollution and residual chlorine. The PVA-0.20/PA/PVA-0.20 TFC, prepared with a 0.20%w/v PVA solution, achieved a pure water flux of up to 22.05 L m−2 h−1 bar−1 (LMH/bar), which was 2.92 times higher than that of the control TFC membrane. Additionally, it demonstrated a salt rejection rate exceeding 96% for Na2SO4 and over 99% for Congo Red (CR) and Victoria Blue B (VB). In comparison with the control TFC membrane, the PVA-0.20/PA/PVA-0.20 membrane exhibited significantly enhanced resistance to pollution. Following immersion in a 1000 ppm NaClO solution for 4 h, the rejection rate of the control TFC membrane decreased markedly and that of the PVA-0.20/PA/PVA-0.20 membrane decreased marginally, indicating excellent resistance to residual chlorine. Due to the robust overall performance of the PVA/PA/PVA membrane, it holds potential advantages for application in treating reclaimed water or slightly polluted water. [ABSTRACT FROM AUTHOR]

The present investigation highlights the necessity of monitoring some basic physico-chemical water quality indicators and their phytotoxic effect using ecotoxicological bioassays such as "seed germination tests." The phytotoxicity of raw and treated vegetable oil refinery wastewater (VORW) using different treatment processes was assessed through some physiological responses (relative seed germination (RSG), seedling elongation, and germination index (GI)) using Lactuca sativa cultivar. Biotest results of different raw water samples revealed a noticeable correlation between the organic matter content and water phytotoxicity. In fact, VORW showed a very low RSG (17 ± 0.7 to –47 ± 0.58%) and high phytotoxic effects (GI < 50%). The use of coagulation/flocculation (CF) allowed a satisfactory phytotoxicity removal where RSG obtained ranged from 83 ± 1.58 to 90 ± 1.2%. However, the effluent still presents high to moderate phytotoxicity since GI remained below 80% which indicates the presence of toxic elements remaining after CF treatment. When VORW were treated using membrane processes, their phytotoxicity was gradually decreased with the decrease in the membrane pore size. The use of microfiltration membranes (MF), with pore size of 5 µm, 1.2 µm, 0.45 µm, and 0.22 µm, showed RSG values ranged from 37 ± 1.15 to 77 ± 1.68% and GI of less than 80% indicating a moderate to high phytotoxicity. However, the use of ultrafiltration (UF) membranes with molecular weight cut-off (MWCO) of 100 kDa, 30 kDa, and 10 kDa made it possible to achieve an RSG of 100% and an IG exceeding 80% showing that the VORW-treated using UF does not exhibit any phytotoxicity effect. Hence, UF appears to be the most efficient and environmentally friendly technology that could be used for safely treated VORW irrigation purposes compared to CF and MF processes. [ABSTRACT FROM AUTHOR]

ABSTRACT Ethyl acetate is at present exclusively produced from fossil resources. Microbial synthesis of this ester from sugar‐rich waste as an alternative is an aerobic process. Ethyl acetate is highly volatile and therefore stripped with the exhaust gas from the bioreactor which enables in situ product recovery. Previous research on microbial formation of ethyl acetate has focused on the kinetics of ester synthesis and in part on the ester stripping, while the separation of the ester from the exhaust gas has hardly been investigated. A mixed matrix membrane was developed consisting of Silikalite‐1 embedded in polydimethylsiloxane which was installed in a radial–symmetrical membrane module. Evaluation of the separation of ethyl acetate was based on the analysis of the composition of the feed and retentate gas by mass spectrometry. The separation efficiency of the membrane was first tested with varied flows of artificial exhaust gas, containing defined amounts of ethyl acetate. A model for describing the separation process was parametrized by the measured data and used to design a real separation experiment. Ethyl acetate produced from delactosed whey permeate by Kluyveromyces marxianus DSM 5422 in a stirred bioreactor gassed with 0.5 vvm air was successfully separated from the exhaust gas by membranes; 93.6% of the stripped ester was separated. Liquid ethyl acetate was recovered by cooling the permeate gas to ‒78°C, whereby 99.75% of the condensed organic compounds were ethyl acetate. This study demonstrates for the first time that microbially produced and stripped ethyl acetate can be effectively separated from the exhaust gas of bioreactors by membrane technology to obtain the ester in high yield and purity. [ABSTRACT FROM AUTHOR]

Background: Production of cheese whey in the EU exceeded 55 million tons in 2022, resulting in lactose-rich effluents that pose significant environmental challenges. To address this issue, the present study investigated cheese-whey treatment via membrane filtration and the utilization of its components as fermentation feedstock. A simulation model was developed for an industrial-scale facility located in Italy's Apulia region, designed to process 539 m3/day of untreated cheese-whey. The model integrated experimental data from ethanolic fermentation using a selected strain of Kluyveromyces marxianus in lactose-supplemented media, along with relevant published data. Results: The simulation was divided into three different sections. The first section focused on cheese-whey pretreatment through membrane filtration, enabling the recovery of 56%w/w whey protein concentrate, process water recirculation, and lactose concentration. In the second section, the recovered lactose was directed towards fermentation and downstream anhydrous ethanol production. The third section encompassed anaerobic digestion of organic residue, sludge handling, and combined heat and power production. Moreover, three different scenarios were produced based on ethanol yield on lactose (YE/L), biomass yield on lactose, and final lactose concentration in the medium. A techno-economic assessment based on the collected data was performed as well as a sensitivity analysis focused on economic parameters, encompassing considerations on cheese-whey by assessing its economical impact as a credit for the simulated facility, dictated by a gate fee, or as a cost by considering it a raw material. The techno-economic analysis revealed different minimum ethanol selling prices across the three scenarios. The best performance was obtained in the scenario presenting a YE/L = 0.45 g/g, with a minimum selling price of 1.43 €/kg. Finally, sensitivity analysis highlighted the model's dependence on the price or credit associated with cheese-whey handling. Conclusions: This work highlighted the importance of policy implementation in this kind of study, demonstrating how a gate fee approach applied to cheese-whey procurement positively impacted the final minimum selling price for ethanol across all scenarios. Additionally, considerations should be made about the implementation of the simulated process as a plug-in addition in to existing processes dealing with dairy products or handling multiple biomasses to produce ethanol. [ABSTRACT FROM AUTHOR]

Given that SOF materials have both inorganic and organic properties and are easy to prepare and structurally designable, this paper carries out the microbehavioral analysis and membrane design of SOF-8, SOF-9, and SOF-10 membranes for the hydrogen purification process of RMFCs. Since three materials have complementary performance characteristics for hydrogen purification, this paper focuses on the gas separation behavior of these three composite membranes using molecular dynamics simulations. Results showed that the SOF-9a+10a composite membranes could 100% block CO 2 and CO, and displayed an excellent H 2 permeability of 6.118 × 105 GPU during H 2 /CO 2 separation, which exceeded the industry standard by nearly 105 times. Additionally, the SOF-9a+8 and SOF-10a+8 composite membranes improved gas selectivity and maintained high H 2 permeability. Moreover, microdiffusion analyses revealed that the small pore sizes and irregular-shaped pore channels effectively hindered CO 2 and CO transport. Microscopic analysis shows the potential of SOF composite membranes for gas separation. [Display omitted] • SOF composite membranes can effectively improve gas selectivity. • Small pore sizes and irregular pore channels can effectively block CO 2 transport. • SOF-9a+10 can 100% intercept CO 2 and CO. • The interaction between gas and membrane affects the gas separation performance. [ABSTRACT FROM AUTHOR]

Robust high‐valence metal–organic framework (MOF) membranes for CO2 separations show great promise for achieving carbon neutrality. Herein, the elegant fabrication of tetravalent zirconium Materials of Institute Lavoisier‐140A (MIL‐140A) membranes are pioneered and validated the intriguing dual role for both CO2‐selective and CO2‐rejective separations by combining structural regulation with the exploitation of the appropriate anisotropic ultramicropores. This inimitable separation ability of "hitting two targets with one arrow" with distinctive molecular size cut‐offs, which originated from the significant orientation transformation, enables the membranes to satisfy multiscenario CO2 capture requirements. The preferred (h0h)‐oriented MIL‐140A membranes exhibit superior mixed CO2/CH4 separation capacities (a separation factor of ≈30), while the highly (200)‐oriented MIL‐140A membranes exhibit remarkable mixed H2/CO2 separation capacities (a separation factor of ≈540), and they both ranked at the top among the present MOF membranes. This work highlights the promising prospects of the fresh MIL‐140 series for a given membrane‐based multiscenario CO2 separation application through microstructure customization and manipulation. [ABSTRACT FROM AUTHOR]

Crystalline metal–organic frameworks (MOFs) have garnered extensive attention owing to their highly ordered porous structure and physicochemical properties. However, their practical application often requires their integration with various substrates, which is challenging because of their weakly adhesive nature and the diversity of substrates that exhibit different properties. Herein, we report the use of amorphous metal–phenolic network coatings to facilitate the growth of crystalline MOF coatings on various particle and planar substrates. Crystalline MOFs with different metal ions and morphologies were successfully deposited on substrates (13 types) of varying sizes, shapes, and surface chemistries. Furthermore, the physicochemical properties of the coated crystalline MOFs (e.g. composition, thickness) could be tuned using different synthesis conditions. The engineered MOF‐coated membranes demonstrated excellent liquid and gas separation performance, exhibiting a high H2 permeance of 63200 GPU and a H2/CH4 selectivity of 10.19, likely attributable to the thin nature of the coating (~180 nm). Considering the vast array of MOFs available (>90,000) and the diversity of substrates, this work is expected to pave the way for creating a wide range of MOF composites and coatings with potential applications in diverse fields. [ABSTRACT FROM AUTHOR]

Capturing carbon dioxide (CO2) from flue gases is a crucial step towards reducing CO2 emissions. Among the various carbon capture methods, facilitated transport membranes (FTMs) have emerged as a promising technology for CO2 capture owing to their high efficiency and low energy consumption in separating CO2. However, FTMs still face the challenge of losing mobile carriers due to weak interaction between the carriers and membrane matrix. Herein, we report a sulfonated chitosan (SCS) gel membrane with confined amine carriers for effective CO2 capture. In this structure, diethylenetriamine (DETA) as a CO2‐mobile carrier is confined within the SCS gel membrane via electrostatic forces, which can react reversibly with CO2 and thus greatly facilitate its transport. The SCS ion gel membrane allows for the fast diffusion of amine carriers within it while blocking the diffusion of nonreactive gases, like N2. Thus, the prepared membrane exhibits exceptional CO2 separation capabilities when tested under simulated flue gas conditions with CO2 permeance of 1155 GPU and an ultra‐high CO2/N2 selectivity of above 550. Moreover, the membrane retains a stable separation performance during the 170 h continuous test. The excellent CO2 separation performance demonstrates the high potential of gel membranes for CO2 capture from flue gas. [ABSTRACT FROM AUTHOR]

Photocatalytic membranes (PM) have been investigated as an antifouling strategy for membrane separation processes. Coating ceramic membranes with photocatalytic layers can provide a highly active surface capable of degrading foulants and smaller molecules improving the membrane's performance when the surface is irradiated by a suitable light. Nevertheless, the coating process often leads to pore blockage due to the formation or deposition of thick layers of photocatalyst on membrane surfaces, which modifies the original membranes' average pore size and reduces membrane permeability. A facile sol-gel dip coating process was used to produce PM without modifying the original surface morphology of alumina microfiltration membranes. A 3.7-fold increase in permeate volume after 90 min of permeation of an acetaminophen solution in continuous filtration mode under UV light (λ = 365 nm LED, 10W) using titania as photocatalyst compared to the bare alumina membrane without irradiation. Furthermore, fouling modelling proved a reduction in the fouling constant, while fouling mechanisms were not modified. Raman analysis showed 100% anatase formed on the membrane surface. Although membranes could remove up to 87% TOC for oily wastewater filtration, antifouling capabilities for this type of effluent were not observed for the photocatalytic membranes mainly due to fouling inside the pores and light attenuation due to the thick fouling layer on the membrane surface. [ABSTRACT FROM AUTHOR]

A series of poly(ethylene glycol)‐block‐poly(propylene glycol) (PEG/PPG)‐ and 5,6‐di(9H‐carbazol‐9‐yl)isoindoline‐1,3‐dione (2CZPImide)‐based crosslinked rubbery polymer membranes, denoted as PEG/PPG‐2CZPImide (x:y), are prepared from the norbornene‐functionalized PEG/PPG oligomer (NB‐PEG/PPG‐NB) and 2‐(bicyclo[2.2.1]hept‐5‐en‐2‐ylmethyl)‐5,6‐di(9H‐carbazol‐9‐yl)isoindoline‐1,3‐dione (2CZPImide‐NB) via ring‐opening metathesis polymerization (ROMP). The molar ratio (x:y) of the NB‐PEG/PPG‐NB (x) to 2CZPImide‐NB (y) monomers is varied from 10:1 to 6:1. X‐ray diffraction (XRD), scanning electron microscopy‐energy dispersive X‐ray spectroscopy (SEM‐EDS), and pure gas permeability studies reveal that the comonomer 2CZPImide‐NB successfully increases the d‐spacing among the crystalline PEG/PPG segments, hence enhancing the diffusivity of gases through the membranes. The synthesized membranes exhibit good CO2 separation performance, with CO2 permeabilities ranging from 311.1 to 418.1 Barrer and CO2/N2 and CO2/CH4 selectivities of 39.4–52.0 and 13.4–16.0, respectively, approaching the 2008 Robeson upper bound. Moreover, PEG/PPG‐2CZPImide (6:1), displaying optimal CO2 permeability and CO2/N2 and CO2/CH4 selectivities, shows long‐term stability against physical aging and plasticization resistance up to 20 days and 10 atm, respectively. [ABSTRACT FROM AUTHOR]

Despite longstanding excitement and progress toward understanding liquid-liquid phase separation in natural and artificial membranes, fundamental questions have persisted about which molecules are required for this phenomenon. Except in extraordinary circumstances, the smallest number of components that has produced large-scale, liquid-liquid phase separation in bilayers has stubbornly remained at three: a sterol, a phospholipid with ordered chains, and a phospholipid with disordered chains. This requirement of three components is puzzling because only two components are required for liquid-liquid phase separation in lipid monolayers, which resemble half of a bilayer. Inspired by reports that sterols interact closely with lipids with ordered chains, we tested whether phase separation would occur in bilayers in which a sterol and lipid were replaced by a single, joined sterol-lipid. By evaluating a panel of sterol-lipids, some of which are present in bacteria, we found a minimal bilayer of only two components (PChemsPC and diPhyPC) that robustly demixes into micron-scale, liquid phases. It suggests an additional role for sterol-lipids in nature, and it reveals a membrane in which tie-lines (and, therefore, the lipid composition of each phase) are straightforward to determine and will be consistent across multiple laboratories. [ABSTRACT FROM AUTHOR]

As global demand for renewable energy and electric vehicles increases, the need for lithium has surged significantly. Extracting lithium from salt lake brine has become a cutting-edge technology in lithium resource production. In this study, two-dimensional (2D) GO/MXene composite membranes were fabricated using pressure-assisted filtration with a polyethyleneimine (PEI) coating, resulting in positively charged PEI-GO/MXene membranes. These innovative membranes, taking advantage of the synergistic effects of interlayer channel sieving and the Donnan effect, demonstrated excellent performance in Mg2+/Li+ separation with a mass ratio of 20 (Mg2+ rejection = 85.3%, Li+ rejection = 16.7%, SLi,Mg = 5.7) in simulated saline lake brine. Testing on actual salt lake brine in Tibet, China, confirmed the composite membrane's potential for effective Mg2+/Li+ separation. In the actual brine test with high concentration, Mg2+/Li+ after membrane separation is 2.2, which indicates that the membrane can significantly reduce the concentration of Mg2+ in the brine. Additionally, the PEI-GO/MXene composite membrane demonstrated strong anti-swelling properties and effective divalent ion rejection. This research presents an innovative approach to advance the development of 2D membranes for the selective removal of Mg2+ and Li+ from salt lake brine. [ABSTRACT FROM AUTHOR]

As a promising wastewater treatment technology, ultrafiltration membranes face challenges related to fouling and flux reduction. To enhance these membranes, various strategies have been explored. Among them, the incorporation of nano-activated carbon (nAC) powder has emerged as an effective method. In this study, composite polysulfone (PSF) ultrafiltration membranes were fabricated using nAC powder at concentrations ranging from 0 to 8 wt.%. These membranes underwent comprehensive investigation, including assessments of membrane morphology, hydrophilicity, pure water flux, equilibrium water content, porosity, average pore size, and protein separation. The addition of activated carbon improved several desirable properties. Specifically, the hydrophilicity of the PSF membranes was enhanced, with the contact angle reduced from 69° to 58° for 8 wt.% of nAC composite membranes compared to the pristine PSF membrane. Furthermore, the water flux test revealed that 6 wt.% activated carbon-based membranes exhibited the highest flux, with a nearly 3 times improvement at 2 bar. Importantly, this enhancement did not compromise the protein rejection. Additionally, the introduction of nAC had a significant effect on the membrane's pore size by improving lysozyme rejection up to 40%. Overall, these findings will guide the selection of the optimal concentration of nAC for PSF ultrafiltration membranes. [ABSTRACT FROM AUTHOR]

The use of deep eutectic solvents (DESs) for the preparation of polymer membranes for environmental separation technologies is comprehensively reviewed. DESs have been divided into five categories based on the hydrogen bond donor (HBD) and acceptor (HBA) that are involved in the production of the DESs, and a wide range of DESs' physicochemical characteristics, such as density, surface tension, viscosity, and melting temperature, are initially gathered. Furthermore, the most popular techniques for creating membranes have been demonstrated and discussed, with a focus on the non-solvent induced phase separation (NIPS) method. Additionally, a number of studies have been reported in which DESs were employed as pore formers, solvents, additives, or co-solvents, among other applications. The addition of DESs to the manufacturing process increased the presence of finger-like structures and macrovoids in the cross-section and, on numerous occasions, had a substantial impact on the overall porosity and pore size. Performance data were also gathered for membranes made for various separation technologies, such as ultrafiltration (UF) and nanofiltration (NF). Lastly, DESs provide various options for the functionalization of membranes, such as the creation of various liquid membrane types, with special focus on supported liquid membranes (SLMs) for decarbonization technologies, discussed in terms of permeability and selectivity of several gases, including CO2, N2, and CH4. [ABSTRACT FROM AUTHOR]

Next-generation wearable electronics demand lightweight membranes integrated with multiple functionalities. Here, heterogeneous composite membranes of carbon nanotubes (CNTs) from vertical orientation to spreading are developed with a simple method to address this challenge. Magnetite (Fe3O4) nanoparticles with polydopamine ligands were uniformly adsorbed on acidified CNTs, resulting in magnetic responsive CNTs. Applying a magnet above the filtration membrane yielded a freestanding CNT/Fe3O4 heterogeneous membrane with an adaptive gradient structure of CNTs transitioning from vertically aligned to horizontally spread. The heterogeneous surfaces of the magnetically aligned CNT/Fe3O4 composite membranes displayed distinct differences in water contact angle, electrical conductivity, and thermal conductivity. Based on the adaptive alignment of CNTs, the fabricated freestanding heterogeneous composite membranes exhibited remarkable Joule heating effect and enhanced electromagnetic shielding effect. [ABSTRACT FROM AUTHOR]

[Display omitted] • A fully bio-based filtration membrane (SGFM) is fabricated based on the gel-confined phase separation. • SGFM can provide lower pressure drop, higher filtration efficiency, and superior microbial survivability for bioaerosol sampling. • By simplifying the elution and extraction process, maximum sample transfer and vigorous recovery was achieved by SGFM. • Green capture was first proposed in air filtration for accurate and sensitive detection of airborne microbes. Air filtration has become a desirable route for collecting airborne microbes. However, the potential biotoxicity and sterilization of current air filtration membranes often lead to undesired inactivation of captured microbes, which greatly limits microbial non-traumatic transfer and recovery. Herein, we report a gel-confined phase separation strategy to rationally fabricate a fully bio-based filtration membrane (SGFM) using soluble soybean polysaccharide and gelatin. The versatile SGFM features fascinating honeycomb micro-nano architecture and hierarchical interconnected porous structures for microbial capture, and achieves a lower pressure drop, higher interception efficiency (99.3%), and superior microbial survivability than commercial gelatin filtration membranes. Particularly, the water-dissolvable SGFM can greatly simplify the elution and extraction process after bioaerosol sampling, thereby bringing about maximum sample transfer and vigorous recovery of collected microbes. Meanwhile, green capture coupled with ATP bioluminescence endows the SGFM with rapid and quantitative detection capability for airborne microbes. This work may pave the way for designing green protocols for the detection of bioaerosols. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering 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.)

During the construction of supramolecular polymers of smaller nanoparticles/nanoclusters bearing hierarchy and homochirality, the mechanism understanding via intuitive visualization and precise cross-scale chirality modulation is still challenging. For this goal, a cooperative self-assembly strategy is here proposed by using ionic complexes with uniform chemical composition comprising polyanionic nanocluster cores and surrounded chiral cationic organic components as monomers for supramolecular polymerization. The single helical polymer chains bearing a core-shell structure at utmost length over 20 μm are demonstrated showing comparable flexibility resembling covalent polymers. A nucleation-elongation growth mechanism that is not dealt with in nanoparticle systems is confirmed to be accompanied by strict chiral self-sorting. A permeable membrane prepared by simple suction of such supramolecular polymers displays high enantioselectivity (e.e. 98% after four runs) for separating histidine derivatives, which discloses a benefiting helical chain structure-induced functionalization for macroscopic supramolecular materials in highly efficient racemate separation. Understanding the mechanism for supramolecular polymer assembly from nanoclusters bearing hierarchy and homochirality is challenging. Here, the authors report a cooperative self-assembly strategy using ionic complexes with chiral surfactants through a nucleation-elongation growth mechanism with chiral self-sorting and prepare a permeable membrane for the separation of histidine derivatives. [ABSTRACT FROM AUTHOR]

Membrane materials that resist nonspecific or specific adsorption are urgently required in widespread practical applications, such as water purification, food processing, and life sciences. In water purification, inevitable membrane fouling not only limits membrane separation performance, leading to a decline in both permeance and selectivity, but also remarkably increases operation requirements, and augments extra maintenance costs and higher energy consumption. In this work, we report a freestanding interfacial polymerization (IP) fabrication strategy for in situ creation of asymmetric block copolymer (BCP) nanofilms with antifouling properties, greatly outperforming the conventional surface post‐modification approaches. The resultant free‐standing asymmetric BCP nanofilms with highly‐dense, highly‐hydrophilic polyethylene glycol (PEG) brushes on one side, can be readily formed via a typical IP process of a well‐defined double‐hydrophilic BCP composed of a highly‐efficient antifouling PEG block and a membrane‐forming multiamine block. The asymmetric BCP nanofilms have been applied for efficient and sustainable natural water purification, demonstrating extraordinary antifouling capabilities accompanied with superior separation performance far beyond commercial polyamide nanofiltration membranes. The antifouling behaviors of asymmetric BCP nanofilms derived from the combined effect of the hydration layer, electrostatic repulsion and steric hindrance were further elucidated by water flux and fouling resistance in combination with all‐atom molecular dynamics (MD) simulation. This work opens up a new avenue for the large‐scale and low‐cost creation of broad‐spectrum, asymmetric membrane materials with diverse functional "defect‐free" surfaces in real‐world applications. [ABSTRACT FROM AUTHOR]