Sustainable Separation Processes Research Articles

A metal–organic frameworks-imprinted emulsion interface with dynamic size- and site-selective recognition for significantly enhanced flavoniods extraction

The boronic acid suspended Cr based MIL-100 (MIL-100-B) sorbents have been widely used to separation of cis-diol containing molecules. However, it’s still challenging in fabrication of high performance metal organic frameworks (MOFs) due to its irregular size and low content of functional groups. For improving identification efficiency, the emulsion microreactor were firstly designed to purify MIL-100-B prior to their use. Herein, a highly ordered MOFs-imprinted polymer microsphere was synthesized by O/W Pickering emulsion template, which can highly selective separation of MIL-100-B via the synergistic effect of boronic acid sites and imprinted cavities. The obtained purified H-MIL-100-B exhibited the uniform size and abundant boronic acid groups (B elements ratio up to 27.37 %). The emulsion imprinted microsphere (EIMs) showed the good selectivity towards MIL-100-B. Additionally, the obtained MOF-imprinted microsphere exhibited green, convenient, sustainable separation process towards the purification and recycle of MIL-100-B. The purified MOFs (H-MIL-100-B) were used to specific bind with cis-diol flavoniods naringin (NRG). Satisfactorily, H-MIL-100-B show high adsorption amount (43.69μmol/g at 308 K), fast capture kinetics (160 min), high selectivity and excellent regenerability (up to seven cycles). Remarkably, the purified NRG solutions displayed lasting antibacterial activity against Staphylococcus aureus (S. aureus) with inhibition zone of 13.47 mm. More importantly, the H-MIL-100-B could effectively promote the specific recognition ability of NRG by reducing matrix interference and improving purification efficiency (93.93 %) from complex natural extracts. A high score (0.75) was predicted via analytical GREEnness (AGREE) approaches, demonstrating environmentally friendly and greenness of separation process. The MOFs-imprinted emulsion microspheres possessed dynamic recognition properties towards target MOFs, thus opening new direction for the development of convenient and efficient microreactor for the purification of other functional MOFs.

Widening the stimuli-responsiveness of aqueous biphasic systems by changing the ionic liquid cation basicity.

Herein we demonstrate the formation of new stimuli-responsive aqueous biphasic systems (ABS), able to respond simultaneously to temperature and pH, or just to one stimulus, therefore allowing the design of more sustainable separation processes. This dual behavior is achieved with ABS formed by mono or dicationic protic ionic liquids as phase-forming components, being defined by the ionic liquid cation chemical structure or its basicity. While ABS comprising monocationic ionic liquids only respond to the effect of temperature, systems comprising dicationic ionic liquids are simultaneously affected by both temperature and pH variations. Dicationic ionic liquids are here identified as the key to unlock a double response to stimuli, which is due to the presence of two pKa values afforded by the cation. The reported findings contribute to increase the customizability of double stimuli-responsive ABS based on ionic liquids, whose development was up to date limited to ionic liquids bearing pH-responsive anions, opening the door towards the development of more sustainable separation processes.

A chemical-free magnetophoretic approach for recovering magnetic particles in microalgae removal through magnetic separation

Magnetic separation can swiftly remove many substances (e.g., biomolecules, cells, and viruses) from water. In algal bloom mitigation and biomass dehydration, magnetic particles (MPs) with proper surface modifications could effectively attract and remove algae from the impaired water body. It has long been expected to recover and reuse magnetic nanoparticles or particles to reduce the algal removal cost and potential adverse effects on the environment. This study evaluated the use of a tunable magnetic field to remove algae using functionalized MPs coated with polymers: polyethyleneimine (PEI), chitosan (CTS), and cetyltrimethyl ammonium bromide (CTAB), whose recovery and reuse were examined. The results show that PEI-coated MPs and CTS-coated MPs at the coating density of 2.3 g-cationic polymers·g-MPs−1 achieved higher removal efficiencies of 88.61 ± 9.12% and 73.19 ± 0.37%, respectively, toward a model algal cell (i.e., Scenedesmus obliquus) within a 5-min separation time. In contrast, CTAB-coated MPs and pristine MPs exhibited lower removal efficiencies (47.46 ± 0.3% and 52.69 ± 0.44%, respectively). Furthermore, the removal efficiency of PEI-coated MPs was further improved to over 95% under pH 7, the highest magnetic field of 40 mT, and algogenic organic matter-free conditions. Adsorption kinetics and isotherm analysis revealed that chemical and physical interactions drive the adsorption of a monolayer of algal cells on the surface of magnetic particles. Atomic force microscopy and quartz crystal microbalance confirmed a strong adhesion force and rate between functionalized MPs and algae, which affect both algal removal efficiency and MPs recovery from algae-MPs aggregates. The extended Derjaguin−Landau−Verwey−Overbeek (EDLVO) theory predicted a strong attractive force between algae and cationic polymer-coated MPs, which supported the enhanced algal removal. Finally, almost 99% of the four MPs could be recovered from separated algae-MPs aggregates within 30 s under the strong magnetic field and exhibited excellent magnetic responsiveness and reusability in further separation cycles. This study establishes a foundation for coagulant-free algae removal and enables the potential sustainable separation processes.

Thymol: nature's solvent for sustainable hollow fiber fabrication

Sustainable separation processes like membrane technology are crucial for chemical and pharmaceutical industries. Membrane fabrication needs green materials.

A novel sustainable separation process based on special azeotropic behavior of benzene/ethanol/butanone: Process design and multi-performance evaluation

Special azeotropic behaviors of complex mixtures can be used to develop distillation processes to realize energy-saving separation. Based on the residual curves of the system at different pressures and an examination of the impact of several extractants on the relative volatility, the pressure-swing distillation (PSD) process and the extractive distillation (ED) process were proposed to separate benzene/ethanol/butanone azeotrope. According to the characteristic of the azeotropic disappearance of ethanol/butanone with increasing pressure, two new extractive pressure-swing distillation (EPSD) processes were developed and compared with PSD as well as ED. To be able to determine the optimal operating parameters for various processes, the non-dominated sorting genetic algorithm II (NSGA-Ⅱ) was utilized. Heat integration was designed for the EPSD processes to reduce energy consumption. The above processes were evaluated in four aspects of the economy, energy, environment and exergy. The relationship between the four performances of different processes and the normal distance was discussed. The results indicate that the EPSD processes show better performance than the ED and PSD processes. Compared with the two EPSD processes, the total annual cost (TAC) of the heat integrated EPSD processes (HI-EPSD) was reduced by 13.2% and 14.4%, the total gas emissions of CO2, SO2 and NOX were also reduced by 23.6% and 27.2%, respectively. Hence, coupling the ED process with the PSD process and heat integration can both better improve the separation performance of distillation.

The sustainable recovery of rare earth in the leaching solution of Baotou minerals with extraction-precipitation strategy based on fatty acids

To research and develop sustainable extraction-precipitation strategy, the recovery of rare earth (RE) was studied by using mono and binary carboxylic acids, namely lauric acid (LA), myristic acid (MA), sebacic acid (SA) and dodecanedioic acid (DA). Compared with the other carboxylic acids, LA has better precipitation performance and selectivity for RE. It was successfully used to concentrate the leaching solution of Baotou minerals to 227 g/L. RE sulfate was also transformed into RE chloride with high solubility. Ca and Mg impurities in the leachate can be effectively eliminated. The particle size of formed RE concentrate is obviously larger than that those produced by industrial precipitants, which helps to improve the separation efficiency. Unlike oxalic acid and ammonium bicarbonate, the extraction-precipitant studied in this article can be reused to avoid the generation of oxalic acid wastewater, ammonia nitrogen wastewater, and carbon dioxide. The obtained RE concentrates have good separation performances and low solubilities in aqueous phase. The mechanism of RE extraction-precipitation by LA was examined by slope analysis, XPS and IR spectra. LA showed good stability during the recovery and recycling processes. Based on the above research, the extraction-precipitation of fatty acid (FA) provides a simple, efficient and sustainable separation process for Baotou minerals.

Biosorption of methylene blue and malachite green from single and binary solutions by Pinus pinaster bark

Aiming to develop a sustainable separation process reducing the water pollution, in this work Pinus pinaster (cluster pine) bark from a wood veneer industry was used for methylene blue and malachite green removal from aqueous systems. For single adsorption, the influence of time (up 8 h), adsorbent dose (2,5 - 5 - 10 g·L-1), temperature (25 ºC - 40 ºC - 60 ºC), pH (2 - 4 - 6) and particle size (0,1 mm - 0,5 mm, 0,5 mm - 1 mm and 1,6 mm - 2 mm) on adsorption was investigated. To study the initial concentration effect on binary adsorption, different concentrations (0 - 5 - 25 - 50 mg·L-1) were used at 25 ºC, natural pH and a dose of 5 g·L-1. High efficiency was obtained at pH = 4 (natural pH), dose of 5 g·L-1 and particle size of 0,5 - 1 mm. Adsorption percentages higher than 70 % were reached in less than one hour, with removal almost complete at equilibrium in single systems, without temperature influence. Methylene blue was slightly better adsorbed by bark. In binary systems, dyes exhibited competitive adsorption, decreasing their removal, especially increasing the initial concentration of the other dye. Dyes adsorption followed the pseudo-second order kinetic model, whereas the Langmuir isotherm explained adsorption equilibria in mono-component systems. High adsorption capacities (41,7 mg·g-1 for malachite green and 50,0 mg·g-1 for methylene blue) were obtained at 40 ºC and natural pH indicating that pine bark can be effectively used as biosorbent.

Polysulfone ultrafiltration membranes fabricated from green solvents: Significance of coagulation bath composition

Even though membranes can lead to more environmentally sustainable separation processes, membrane casting typically involves toxic organic solvents. Recently, there has been increasing interest in substituting these toxic solvents for green solvents. In this study, polysulfone ultrafiltration membranes were fabricated by nonsolvent induced phase separation using two green, bio-derived solvents: Cyrene and gamma-valerolactone (GVL). The effect of coagulation bath composition was investigated, with water, ethanol, and water/ethanol mixtures tested as nonsolvents in the bath. Membranes were characterized and their performance was tested by dead-end filtration. For both Cyrene and GVL, using pure water in the coagulation bath resulted in membranes with residual solvent trapped inside. During dead-end filtration, these membranes were either impermeable (in the case of GVL) or had very low bovine serum albumin (BSA) rejection (in the case of Cyrene). Concentrations of ∼ 50–75 v% ethanol in the coagulation bath led to improved solvent removal and better pore formation, as indicated by scanning electron microscopy. These membranes also had higher flux and rejection. For example, membranes cast using Cyrene with a 65:35 volumetric ratio of ethanol:water in the coagulation bath achieved 70.1 L/m2/h water flux at 2.41 bar and 96.7 % BSA rejection. Additionally, the effect of humidity on membranes cast using GVL was investigated. Membranes cast under moderate humidity had novel surface morphologies with porous dimples ∼ 1 µm wide. Overall, these results show that Cyrene and GVL are promising solvents for preparing polysulfone ultrafiltration membranes. The work highlights the importance of relating membrane properties to casting conditions.

Direct prediction of gas adsorption via spatial atom interaction learning

Physisorption relying on crystalline porous materials offers prospective avenues for sustainable separation processes, greenhouse gas capture, and energy storage. However, the lack of end-to-end deep learning model for adsorption prediction confines the rapid and precise screen of crystalline porous materials. Here, we present DeepSorption, a spatial atom interaction learning network that realizes accurate, fast, and direct structure-adsorption prediction with only information of atomic coordinate and chemical element types. The breakthrough in prediction is attributed to the awareness of global structure and local spatial atom interactions endowed by the developed Matformer, which provides the intuitive visualization of atomic-level thinking and executing trajectory in crystalline porous materials prediction. Complete adsorption curves prediction could be performed using DeepSorption with a higher accuracy than Grand canonical Monte Carlo simulation and other machine learning models, a 20-35% decline in the mean absolute error compared to graph neural network CGCNN and machine learning models based on descriptors. Since the established direct associations between raw structure and target functions are based on the understanding of the fundamental chemistry of interatomic interactions, the deep learning network is rationally universal in predicting the different physicochemical properties of various crystalline materials.

Prospects of artificial intelligence in the development of sustainable separation processes

Addressing the urgent need for more energy-efficient separation technologies is paramount in reducing energy consumption and lessening environmental impact as we march toward a carbon-neutral society. The rapid progression of AI and its promising applications in separation science presents new, fascinating possibilities. For instance, AI algorithms can forecast the properties of prospective new materials, speeding up the process of sorbent material innovation. With the ability to analyze vast datasets related to processes, machine learning driven by data can enhance operations to reduce energy wastage and improve error detection. The recent rise of Generative Pretrained Transformer models (GPT) has motivated researchers to construct specialized large-scale language models (LLM) based on a comprehensive scientific corpus of papers, reference materials, and knowledge bases. These models are useful tools for facilitating the rapid selection of suitable separation techniques. In this article, we present an exploration of AI's role in promoting sustainable separation processes, covering a concise history of its implementation, potential advantages, inherent limitations, and a vision for its future growth.

Merging Renewable Carbon-Based Materials and Emerging Separation Concepts to Attain Relevant Purification Applications in a Circular Economy

The globe demands a more efficient approach to provide materials and products for the economic and living needs of a modern society. Separation processes have an important role in order to achieve the recoveries and purities required in terms of quality specifications. There are a variety of porous materials taking the role of separation agents which work effectively in many technological industrial applications based on adsorption and membrane processes. The separation agents derived from renewable materials represent a desirable alternative to face the sustainability challenges in industrial settings. In this sense, the biomass residues which are abundant in agroindustrial regions represent an opportunity to tackle the needs for sustainable separation processes. Innovation plays a key role in order to combine renewable materials and emerging separation concepts to find compelling solutions for the needs of water and gas treatment purifications. These solutions are achieved more effectively through the joint research and innovation effort between materials and process aspects. This commentary remarks the fruitful opportunity existing for separation technology to take advantage of biomass residues to be converted into tailor-made separation agents. It focuses on novel separation applications where the biocarbon electroactive properties play a significant role. These technological approaches for biocarbon are beyond its most common use as an activated carbon adsorbent. Recent research contributions providing original solutions on this aspect are discussed here mainly for gas separation of CO2 and volatile organic compounds, freshwater recovery, and electrolyte separation among others. Innovative separation solutions including tailor-made biocarbons are expected to grow at a fast pace in the coming years.

Insight on the sustainable design and multi-objective optimization for separating the ternary azeotropic mixture of toluene/n-butanol/water by natural decanting coupled with pressure swing distillation

The effective recovery of n-butanol (BuOH) and toluene from wastewater via sustainable separation process is critical to promote environmental protection and resource utilization. In this work, we propose a comprehensive methodology to develop a natural decanting coupled with pressure-swing distillation (NDPSD) for the azeotropic separation of BuOH/toluene/water system. Firstly, the thermodynamic topologic insights are employed to analyze the feasibility of the NDPSD. Secondly, conceptual design involving the understanding of mass balance lines, the liquid–liquid envelope, and distillation boundaries were applied to develop initial design of the NDPSD with two different separation sequences (i.e., configurations). Then, both initial designs are optimized to obtain the optimum column configurations via an improved non-sorting genetic algorithm, with the total capital and operating cost as dual objective function. Finally, both optimized schemes are heat-integrated for the purpose of energy conservation. The performance of all the developed configurations were examined using three indicators, i.e., economic, environmental, and energy efficiency, and our results revealed that the heat-integrated configuration B with separation sequence of water → BuOH → toluene provides the best economic, environmental, and thermodynamic efficiency.

Recovery Process for Critical Metals: Selective Adsorption of Nickel(II) from Cobalt(II) at Acidic Condition and Elevated Temperature

Effective and sustainable separation processes for critical metals, especially for the physicochemically similar elements nickel and cobalt in battery recycling, are of great interest in the future. Selective adsorption represents a highly potential process for this purpose. In this publication, a silica adsorbent functionalized with an amino-polycarboxylate derivate (HSU331) was investigated regarding the selective adsorption of Ni(II) in the presence of Co(II) in acidic solution (pH range at equilibrium 1.8–2.3) at elevated temperature. Comparable maximum equilibrium loadings ([Formula: see text]) for Ni(II) and Co(II) of 0.59 μmol(Ni(II)) · μmol(Ligand)-1 (18.3 mg(Ni(II)) · g(Adsorbent)-1), and 0.52 μmol(Co(II)) · μmol(Ligand)-1 (16.0 mg(Co(II)) · g(Adsorbent)-1), respectively, were achieved at T = 50°C in single-component experiments. Under competitive conditions, the Ni(II) loading remained constant at 0.60 μmol(Ni(II)) · μmol(Ligand)-1 (18.4 mg(Ni(II)) · g(Adsorbent)-1), while the Co(II) loading drastically decreased to 0.09 μmol(Co(II)) · μmol(Ligand)-1 (2.7 mg(Co(II)) · g(Adsorbent)-1) in an equimolar dual-component system. Calculated stability constants of 3 · 103 and 0.7 · 103 L · mol-1, respectively, for the formed metal ion complexes of Ni(II) and Co(II) onto the adsorbent HSU331, clarify the clear selectivity of the adsorbent towards Ni(II) in the presence of Co(II) even at elevated temperature ( T = 50°C).

Unprecedented water permeation in nanostructured PVDF membranes prepared by unidirectional freezing and surface melting method

Phase inversion has played a vital role in membrane technology by offering the economic viability for producing polymeric membrane in quantity, and it allows for the development of wastewater treatment technologies with the membrane as a promising energy-saving separator. However, most existing phase inversion membranes suffer from low permeance, thus diminishing their advantages in the quest for more efficient and sustainable separation processes. Here, based on unidirectional freezing approach, we showcase a hierarchical porous membrane that outperforms the permeance of the phase inversion membranes without compromising the membranes’ separation capabilities. An unprecedented surface melting atop a frozen membrane cast film promotes the phase inversion in the water phase, which in turn constructs an additional separating layer on membrane surface. These membranes exhibit tuneable pores in the range between 9 and 50 nm and pure water permeation which is 16–25 times higher than that of an equivalent industry standard. Moreover, the synergy between freezing and melting enables a separate design of pore sizes from membrane both surfaces, leading to a dual-skin polymeric membrane showing enhanced functionality throughout its cross-section. With the enhanced efficiencies, these membranes have potential to positively contribute to the current water-energy nexus, by considerably improving the economic and technological viability of many water-treatment and filtration-based separation systems.

Synthesis of Hybrid PVDF–PTFE Membrane Using Nonhazardous Solvent for Ethanol–Water Separation through Membrane Distillation

This work was focussed on synthesizing a polyvinylidene fluoride (PVDF)–polytetrafluoroethylene (PTFE) hybrid flat sheet membrane using a nonhazardous solvent dimethyl sulfoxide (DMSO) for ethanol–water separation via vacuum membrane distillation (VMD). The base polymer (PVDF) concentrations were varied from 12 wt% to 16 wt% and the copolymer (PTFE) loading were ranged from 1 wt% to 2 wt% (e.g., 1.0 wt%, 1.5 wt%, and 2.0 wt%). The morphological characteristics, porosity, and contact angle (CA) were examined for the synthesized membranes. An increased CA was observed when PTFE loading was increased in the dope solution. The addition of PTFE to the dope solution efficiently diminished the formation of micro voids and increased the hydrophobicity of the membrane with improved characteristics. Membrane pore size, porosity, and thickness increased significantly from 0.17 µm to 0.21 µm, 48.37% to 67.79%, and 79.31 µm to 107.62 µm, respectively, within the studied range. A pure PVDF membrane CA of 88° was increased to 117.3° for 2 wt% loaded PTFE in PVDF. The synthesis of PVDF–PTFE hybrid membranes that used DMSO as a solvent and distilled water as a nonsolvent in a coagulation bath appears to be viable for membrane preparation via phase inversion to provide a reliable and sustainable separation process with a safer environment. The performance of the synthesized membrane was studied for flux and the separation factor. The maximum ethanol flux and separation factor obtained were 11 kg/m2/h and 7.0, respectively. This work suggests that the PVDF–PTFE hybrid flat sheet membranes could be used for ethanol separation in VMD.

Adsorptive molecular sieving of linear over branched alkanes using trianglamine host macrocycles for sustainable separation processes

The separation of high-purity linear alkanes from a mixture of linear and branched alkanes is of great importance to the oil and gas industry for the improvement of the gasoline quality. Herein, we investigate the methylene-bridged trianglamines (M-TA) as supramolecular adsorbents for the selective separation of linear alkane isomers. This selectivity depends on the host–guest complexation arising from the size matching between the trianglamines cavity and the linear guest molecules. Moreover, M-TA are highly recyclable with almost no loss of efficiency showing a promising prospect in industrial applications. We believe that the tailored design of host supramolecular entities as smart and selective recognition units for energy-intensive separations will be the preferred future approch towards environmentally friendly and sustainable processes in industrial operations.

Alkyl-Substituted Aminobis(phosphonates)-Efficient Precipitating Agents for Rare Earth Elements, Thorium, and Uranium in Aqueous Solutions.

The efficient and environmentally sustainable separation process for rare earth elements (REE), especially for adjacent lanthanoids, remains a challenge due to the chemical similarity of REEs. Tetravalent actinoids, thorium, and traces of uranium are also present in concentrates of REEs, making their separation relevant. This study reports six simple water-soluble aminobis(phosphonate) ligands, RN[CH2P(O)(OH)2]2 (1 R = CH2CH3, 2 R = (CH2)2CH3, 3 R = (CH2)3CH3, 4 R = (CH2)4CH3, 5 R = (CH2)5CH3, 6 R = CH2CH(C2H5)(CH2)3CH3) as precipitating agents for REEs, Th, and U, as well as gives insight into the coordination modes of the utilized ligands with REEs at the molecular level. Aminobis(phosphonates) 4–6 with longer carbon chains were found to separate selectively thorium, uranium, and scandium from REEs with short precipitation time (15 min) and excellent separation factors that generally range from 100 to 2000 in acidic aqueous solution. Ligands 1–6 also improved separation factors for adjacent lanthanoids in comparison to traditional oxalate precipitation agents. Importantly, precipitated metals can be recovered from the ligands with 3 molar HNO3 with no observed ligand decomposition enabling the possibility of recycling the ligands in the separation process. NMR-monitored pH titrations for 1 showed deprotonation steps at pKa 1.3, 5.55, and >10.5, which indicate that the ligands remain in a deprotonated [L]−1 form in the pH range of 0–4 used in the precipitation studies. 31P NMR titration studies between 1 and M(NO3)3 (M = Y, La, Lu) gave satisfactory fits for 1:3, 1:2, and 1:1 metal–ligand stoichiometries for Y, La, and Lu, respectively, according to an F-test. Therefore, aminobis(phosphonate) precipitation agents 1–6 are likely to form metal complexes with fewer ligands than traditional separation agents like DEHPA, which coordinates to REEs in 1:6 metal–ligand ratio.

Imprinted membranes for sustainable separation processes

The rapid industrial growth and the necessity of recovering and recycling raw materials increased the interest in the production of highly selective and efficient separation tools. In this perspective, a relevant input was given by the membrane-based technology and the production of imprinted membranes, which possess specific recognition properties at molecular and ionic level, offers the possibility of developing sustainable and green processes. Furthermore, the integration of imprinted membranes with traditional or membrane-based approaches is a promising strategy in the logic of process intensification, which means the combination of different operations in a single apparatus. This work discusses the concept and separation mechanisms of imprinted membranes. Furthermore, it presents an overview of their application in organic solvent nanofiltration, for the removal of toxic agents and recovery solvent, as well as valuable compounds. The recent advances in water treatment, such as pesticide removal and recovery of metal ions, are also discussed. Finally, potential applications of imprinted membranes in hybrid processes are highlighted, and a look into the future of membrane separations for water treatment and recovery ofcritical raw materials is offered.

Covalent triazine frameworks composite membrane (CdS/CTF-1) with enhanced photocatalytic in-situ cleaning and disinfection properties for sustainable separation

Photo-assisted catalysis is proposed to be an effective approach to deal with the membrane fouling issue, which restricts the broad application of burgeoning 2D covalent organic frameworks (COF) membranes in sustainable separation process. In this work, a new type of [0D + 2D] composite membrane was developed via covalent triazine frameworks (CTF-1) nanosheets with built-in CdS quantum dots (QDs). The regular skeleton of 2D-CTF-1 facilitated the uniform growth of CdS QDs (3 nm) on the planar nanosheets. CdS/CTF-1 composite membrane exhibits high water flux (>170 L m −2 h −1 , 0.1 MPa) and high dyes rejection (>94%) via manipulating transportation channels. More importantly, the built-in [0D + 2D]-heterojunction significantly improves the photocatalytic in - situ cleaning and disinfection performance of CdS/CTF-1 membrane, allowing for regenerating permeability (>95%) with the assist of H 2 O 2 during multiple operations. Thus, we provide a prospective strategy to resolve the membrane fouling issues and enable the practical application of 2D membranes for continuous separation. Photocatalytic in - situ cleaning CdS/CTF-1 composite membrane achieves efficient and continuous separation. • We literally resolve the fouling issue of 2D COF membranes for sustainable separation. • A novel [0D + 2D] membrane was developed by embedding CdS QDs in CTF-1 nanosheets. • CdS/CTF-1 membrane shows improved permeability due to additional channels. • CdS QDs enhance the photocatalytic in - situ cleaning and disinfection performance. • CdS/CTF-1 membrane regenerates its permeability >95% via sunlight illumination.

Sustainable Direct Recycling of Lithium‐Ion Batteries via Solvent Recovery of Electrode Materials

AbstractSeparation of electrode materials from their current collectors is an enabling step toward recovering critical materials from spent lithium‐ion batteries. In the presented research, a highly efficient, cost‐effective, and environmentally sustainable separation process was developed for that purpose. Ethylene glycol, a vital commodity chemical as an antifreeze and polymer precursor, is used to delaminate electrode materials at low temperatures in seconds without altering the crystalline structure and morphology of active electrode materials. The recovered current collectors were intact without any corrosion. The authors also found that the solvent could be continuously reused, leading to the development of a closed‐loop ecosystem and lithium‐ion battery circular economy. The ultrafast delamination was driven by the competitive inhibition of binding through the weakening of hydrogen bonding. The ethylene glycol‐based separation is a sustainable electrode recovery process that paves the way for battery recycling.