The presence of chirality,a fundamental attribute found in nature,is of great significance in the field of pharmaceutical science.Chiral drugs are unique in that their molecular structure is non-superimposable on its ...The presence of chirality,a fundamental attribute found in nature,is of great significance in the field of pharmaceutical science.Chiral drugs are unique in that their molecular structure is non-superimposable on its mirror image.This stereoisomerism significantly impacts the functionality,metabolic pathway,effectiveness,and safety of chiral medications.The enantiomers of chiral drugs can exhibit diverse pharmacological effects in the human body.As a result,it is essential to separate and purify chiral drugs effectively.Despite the abundance of reports on chiral drug separation membranes,there is a dearth of comprehensive reviews.This paper aims to fill this gap by providing a thorough review from a materials perspective,with a focus on the design and construction of chiral drug separation membranes.Furthermore,it systematically analyzes the separation mechanisms employed by these membranes.The paper also delves into the challenges and prospects related to chiral drug separation membranes,with the intention of imparting valuable insights for further research and development in this field.展开更多
Membrane separation technology has been taken up for use in diverse applications such as water treatment,pharmaceutical,petroleum,and energy-related industries.Compared with the design of membrane materials,the innova...Membrane separation technology has been taken up for use in diverse applications such as water treatment,pharmaceutical,petroleum,and energy-related industries.Compared with the design of membrane materials,the innovation of membrane preparation technique is more urgent for the development of membrane separation technology,because it not only affects physicochemical properties and separation performance of the fabricated membranes,but also determines their potential in industrialized application.Among the various membrane preparation methods,spray technique has recently gained increasing attention because of its low cost,rapidity,scalability,minimum of environmental burden,and viability for nearly unlimited range of materials.In this Review article,we summarized and discussed the recent developments in separation membranes using the spray technique,including the fundamentals,important features and applications.The present challenges and future considerations have been touched to provide inspired insights for developing the sprayed separation membranes.展开更多
Membrane technology holds significant potential for augmenting or partially substituting conventional separation techniques,such as heatdriven distillation,thereby reducing energy consumption.Organic solvent nanofiltr...Membrane technology holds significant potential for augmenting or partially substituting conventional separation techniques,such as heatdriven distillation,thereby reducing energy consumption.Organic solvent nanofiltration represents an advanced membrane separation technology capable of discerning molecules within a molecular weight range of approximately 100-1000 Da in organic solvents,offering low energy requirements and minimal carbon footprints.Molecular separation in non-polar solvent system,such as toluene,n-hexane,and n-heptane,has gained paramount importance due to their extensive use in the pharmaceutical,biochemical,and petrochemical industries.In this review,we presented recent advancements in membrane materials,membrane fabrication techniques and their promising applications for separation in nonpolar solvent system,encompassing hydrocarbon separation,bioactive molecule purification and organic solvent recovery.Furthermore,this review highlighted the challenges and opportunities associated with membrane scale-up strategies and the direct translation of this promising technology into industrial applications.展开更多
Covalent organic skeletons(COFs)have been widely used in gas separation due to their excellent pore structure,high crystallinity,and high specific surface area.In this work,Dha Tab-COF was synthesized by solvothermal ...Covalent organic skeletons(COFs)have been widely used in gas separation due to their excellent pore structure,high crystallinity,and high specific surface area.In this work,Dha Tab-COF was synthesized by solvothermal method and filled in polyether block polyamide(PEBAX)to form mixed matrix membranes(MMMs).Various characterization methods such as Fourier transform infrared spectroscopy(FT-IR),Xray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM)and X-ray diffractometry(XRD)were used to characterize the structure of Dha Tab-COF as well as the MMMs.The effects of operating pressure,operating temperature and the content of Dha Tab-COF particles on the CO_(2)/CH_(4)separation performance of the membranes were investigated.The best separation performance with a CO_(2)permeability of 295.8 barrer(1 barrer=7.52×10^(-18)m^(3)·(STP)·m^(-2)·m·s^(-1)·Pa^(-1))and a CO_(2)/CH_(4)selectivity of 21.6 was achieved when the Dha Tab-COF content is 2%(mass),which were 45.7%and 108.1%higher than that of the pure PEBAX membrane,respectively.展开更多
In the field of modern hydrogen energy,obtaining pure hydrogen and syngas and then being able to use them for green energy production are significant problems.Developing solid oxide fuel cells(SOFC)and catalytic membr...In the field of modern hydrogen energy,obtaining pure hydrogen and syngas and then being able to use them for green energy production are significant problems.Developing solid oxide fuel cells(SOFC)and catalytic membranes for oxygen separation as well as materials for these devices is one of the most likely ways to solve these problems.In this work,the authors’recent studies in this field are reviewed;the fundamentals of developing materials for SOFC cathodes and oxygen separation membranes’permselective layers based on research of their oxygen mobility and surface reactivity are presented.Ruddlesden-Popper phases Ln_(2-x)Ca_(x)NiO_(4+δ)(LnCNO)and perovskite-fluorite nanocomposites PrNi_(0.5)Co_(0.5)O_(3-δ)-Ce_(0.9)Y_(0.1)O_(2-δ)(PNC-YDC)were studied by isotope exchange of oxygen with C_(18)O_(2)and^(18)O_(2)in flow and closed reactors.For LnCNO a high oxygen mobility was shown(D*~10^(-7)cm^(2)/s at 700℃),being provided by the cooperative mechanism of oxygen migration involving both regular and highly-mobile interstitial oxygen.For PNC-YDC dominated a wide fast diffusion channel via fluorite phase and interphases due to features of the redistribution of cations resulting in superior oxygen mobility(D*~10^(-8)cm^(2)/s at 700℃).After optimization of composition and nanodomain structure of these materials,as cathodes of SOFC they provided a high power density,while for asymmetric supported oxygen separation membranes-a high oxygen permeability.展开更多
Synthetic polymer membranes are widely used in many applications,including,among others,water purification,protein separation,and medicine.However,the use of existing polymer membranes faces major challenges,such as t...Synthetic polymer membranes are widely used in many applications,including,among others,water purification,protein separation,and medicine.However,the use of existing polymer membranes faces major challenges,such as the trade-off between permeability and selectivity,membrane fouling,and poor mechanical strength.To address these problems the authors have focused their research on surface/interfacial tailoring and the structure-property relationship of polymer membranes used in liquid separation systems.Progress has been made as follows:(1)a methodology for membrane surface functionalization and nanofiltration(NF)membrane preparation based on mussel-inspired catecholic chemistry was proposed and established;(2)a class of mechanically robust and environmentally-responsive composite membranes with hydrogel pore-filled in rigid macroporous supports was designed and developed;(3)a methodology for surface tailoring and antifouling modification of polymer membranes based on amphiphilic copolymers was created and the scientific implications for amphiphilic polymer membranes elaborated;(4)an adsorption membrane with both filtration and adsorption functions was designed and developed to achieve rapid removal of trace micropollutants,including heavy metal ions,organic dyes,plasticizer,antibiotics,and others.This mini-review briefly summarizes this work.展开更多
Membrane separation technologies,with a broad application prospect in the field of hydrogen separation,are characterized by the simplicity of the devices,high energy efficiency and environmental friendliness.The perfo...Membrane separation technologies,with a broad application prospect in the field of hydrogen separation,are characterized by the simplicity of the devices,high energy efficiency and environmental friendliness.The performance of separation membranes is the primary factor that determines the efficiency of hydrogen separation.Therefore,the development of hydrogen separation membranes is always a research focus.This paper presents and reviews the research developments and features of organic membranes,inorganic membranes and hybrid matrix membranes for hydrogen separations.First,the characterization methods of key index parameters of membrane materials are presented.Second,the performance parameters of different types of membrane are compared.Finally,the trend of technological development of different types of membrane materials is forecast.展开更多
Poly(ethylene-oxide)(PEO)-based membranes have attracted much attention recently for CO2 separation because CO2 is highly soluble into PEO and shows high selectivity over other gases such as CH4 and N2.Unfortunately,t...Poly(ethylene-oxide)(PEO)-based membranes have attracted much attention recently for CO2 separation because CO2 is highly soluble into PEO and shows high selectivity over other gases such as CH4 and N2.Unfortunately,those membranes are not strong enough mechanically and highly crystalline,which hinders their broader applications for separation membranes.In this review discussions are made,as much in detail as possible,on the strategies to improve gas separation performance of PEO-based membranes.Some of techniques such as synthesis of graft copolymers that contain PEO,cross-linking of polymers and blending with long chains polymers contributed significantly to improvement of membrane.Incorporation of ionic liquids/nanoparticles has also been found effective.However,surface modification of nanoparticles has been done chemically or physically to enhance their compatibility with polymer matrix.As a result of all such efforts,an excellent performance,i.e.,CO2 permeability up to 200 Barrer,CO2/N2 selectivity up to 200 and CO2/CH4 selectivity up to 70,could be achieved.Another method is to introduce functional groups into PEO-based polymers which boosted CO2 permeability up to 200 Barrer with CO2/CH4 selectivity between 40 and 50.The CO2 permeability of PEO-based membranes increases,without much change in selectivity,when the length of ethylene oxide is increased.展开更多
A series of organosilica sols are prepared by the polymeric sol–gel method using 1,2-bis(triethoxysilyl)ethane(BTESE)as the precursor.Particle size distributions of the BTESE-derived sols are systematically investiga...A series of organosilica sols are prepared by the polymeric sol–gel method using 1,2-bis(triethoxysilyl)ethane(BTESE)as the precursor.Particle size distributions of the BTESE-derived sols are systematically investigated by carefully adjusting the synthesis parameters(i.e.,water ratios,acid ratios and solvent ratios)in the sol process.In certain conditions,increasing the water ratio or the acid ratio tends to cause larger sol sizes and bimodal particle size distributions.However,higher solvent ratios lead to smaller sol sizes and unimodal particle size distributions.The organosilica membranes prepared from the optimized sols show excellent H_2 permeances(up to 4.2×10^(-7)mol·m^(-2)·s^(-1)·Pa^(-1))and gas permselectitivies(H_2/CO_2 is 9.5,H_2/N_2 is 50 and H_2/CH_4 is 68).This study offers significant insights into the relationship between the sol synthesis parameters,sol sizes and membrane performance.展开更多
Poly（amide-6-b-ethylene oxide）（Pebax1657）/1-butyl-3-methylimidazo-lium bis[trifluoromethyl）sulfonyl]-imide（[Bmim][Tf2N]） blend membranes with different [Bmim][Tf2N] contents were prepared via solution casting a...Poly（amide-6-b-ethylene oxide）（Pebax1657）/1-butyl-3-methylimidazo-lium bis[trifluoromethyl）sulfonyl]-imide（[Bmim][Tf2N]） blend membranes with different [Bmim][Tf2N] contents were prepared via solution casting and solvent evaporation method. The permeation properties of the blend membranes for CO2, N2,CH4 and H2 were studied, and the physical properties were characterized by differential scanning calorimeter（DSC） and X-ray diffraction（XRD）. Results showed that [Bmim][Tf2N] was dispersed as amorphous phase in the blend membranes, which caused the decrease of Tg（PE） and crystallinity（PA）. With the addition of [Bmim][Tf2N], the CO2 permeability increased and reached up to approximately 286 Barrer at 40 wt%[Bmim][Tf2N], which was nearly double that of pristine Pebax1657 membrane. The increase of CO2 permeability may be attributed to high intrinsic permeability of [Bmim][Tf2N], the increase of fractional free of volume（FFV） and plasticization effect. However, the CO2 permeability reduced firstly when the [Bmim][Tf2N]content was below 10 wt%, which may be due to that the small ions of [Bmim][Tf2N] in the gap of polymer chain inhibited the flexibility of polymer chain; the interaction between Pebax1657 and [Bmim][Tf2N]decreased the content of EO units available for CO2 transport and led to a more compact structure. For Pebax1657/[Bmim][Tf2N] blend membranes, the permeabilities of N2, H2 and CH4decreased with the increase of feed pressure due to the hydrostatic pressure effect, while CO2 permeability increased with the increase of feed pressure for that the CO2-induced plasticization effect was stronger than hydrostatic pressure effect.展开更多
The high price and toxicity of ionic liquids(ILs) have limited the design and application of supported ionic liquid membranes(SILMs) for CO_2 separation in both academic and industrial fields. In this work, [Choline][...The high price and toxicity of ionic liquids(ILs) have limited the design and application of supported ionic liquid membranes(SILMs) for CO_2 separation in both academic and industrial fields. In this work, [Choline][Pro]/polyethylene glycol 200(PEG200) mixtures were selected to prepare novel SILMs because of their green and costeffective characterization, and the CO_2/N_2 separation with the prepared SILMs was investigated experimentally at temperatures from 308.15 to 343.15 K. The temperature effect on the permeability, solubility and diffusivity of CO_2 was modeled with the Arrhenius equation. A competitive performance of the prepared SILMs was observed with high CO_2 permeability ranged in 343.3–1798.6 barrer and high CO_2/N_2 selectivity from 7.9 to 34.8.It was also found that the CO_2 permeability increased 3 times by decreasing the viscosity of liquids from 370 to38 m Pa·s. In addition, the inherent mechanism behind the significant permeability enhancement was revealed based on the diffusion-reaction theory, i.e. with the addition of PEG200, the overall resistance was substantially decreased and the SILMs process was switched from diffusion-control to reaction-control.展开更多
Metal-organic polyhedra(MOPs)possess a microporous framework and impose hierarchical constraints on their surface ligands,leading to the long-ignored,logarithmic ligand exchange dynamics.Herein,polymer networks with M...Metal-organic polyhedra(MOPs)possess a microporous framework and impose hierarchical constraints on their surface ligands,leading to the long-ignored,logarithmic ligand exchange dynamics.Herein,polymer networks with MOP as nanoscale cross-linkers(MOP-CNs)can integrate unique ligand exchange dynamics and microporosity,affording vitrimer-like gas separation membranes with promising mechanical performance and(re)processability.All the ligands on the MOP surfaces are confined and correlated via a 3D coordination framework and their neighboring spaces,giving rise to a high energy barrier for ligand exchange.Therefore,MOP-CNs demonstrate high mechanical strengths at room temperature due to their negligible ligand dynamics.The thermo-activated ligand exchange process with integrated network topology enables facile(re)processing and high solvo-resistance at high temperatures.This facilitates Arrhenius type temperature dependence of flowability and stress relaxation,giving rise to the simultaneous achievement of promising mechanical strengths and(re)processability.Finally,the cage topologies of MOPs endow the materials with a bonus microporous feature and spur their applications as gas separation membranes.展开更多
Mixed matrix hollow fiber membranes（MMHFMs）filled with metal-organic frameworks（MOFs）have great potential for energy-efficient gas separation processes,but the major hurdle is polymer/MOFs interfacial defects and ...Mixed matrix hollow fiber membranes（MMHFMs）filled with metal-organic frameworks（MOFs）have great potential for energy-efficient gas separation processes,but the major hurdle is polymer/MOFs interfacial defects and membrane plasticization.Herein,lab-synthesized MIL-53 was post-functionalized by aminosilane grafting and subsequently incorporated into Ultem-1000 polymer matrix to fabricate high performance MMHFMs.SEM,DLS,XRD and TGA were performed to characterize silane-modified MIL-53（S-MIL-53）and prepared MMHFMs.Moreover,the effect of MOFs loading was systematically investigated first;then gas separation performance of MMHFMs for pure and mixed gas was evaluated under different pressures.MMHFMs containing post-functionalized S-MIL-53 achieved remarkable gas permeation properties which was better than model predictions.Compared to pure HFMs,CO2permeance of MMHFM loaded with 15%S-MIL-53 increased by 157%accompanying with 40%increase for CO2/N2selectivity,which outperformed the MMHFM filled with naked MIL-53.The pure and mixed gas permeation measurements with elevated feed pressure indicated that incorporation of S-MIL-53 also increased the resistance against CO2plasticization.This work reveals that post-modified MOFs embedded in MMHFMs facilitate the improvement of gas separation performance and suppression of membrane plasticization.展开更多
A microporous zirconia membrane with hydrogen permeance about 5 × 10-8mol·m-2·s-1·Pa-1, H2/CO2 permselectivity of ca. 14, and excellent hydrothermal stability under steam pressure of 100 k Pa was f...A microporous zirconia membrane with hydrogen permeance about 5 × 10-8mol·m-2·s-1·Pa-1, H2/CO2 permselectivity of ca. 14, and excellent hydrothermal stability under steam pressure of 100 k Pa was fabricated via polymeric sol–gel process. The effect of calcination temperature on single gas permeance of sol–gel derived zirconia membranes was investigated. Zirconia membranes calcined at 350 °C and 400 °C showed similar single gas permeance, with permselectivities of hydrogen towards other gases, such as oxygen, nitrogen, methane, and sulfur hexa fluoride, around Knudsen values. A much lower CO2permeance（3.7 × 10-9mol·m-2·s-1·Pa-1）was observed due to the interaction between CO2 molecules and pore wall of membrane. Higher calcination temperature, 500 °C, led to the formation of mesoporous structure and, hence, the membrane lost its molecular sieving property towards hydrogen and carbon dioxide. The stability of zirconia membrane in the presence of hot steam was also investigated. Exposed to 100 k Pa steam for 400 h, the membrane performance kept unchanged in comparison with freshly prepared one, with hydrogen and carbon dioxide permeances of 4.7 × 10-8and ~ 3 × 10-9mol·m-2·s-1·Pa-1, respectively. Both H2 and CO2permeances of the zirconia membrane decreased with exposure time to 100 k Pa steam. With a total exposure time of 1250 h, the membrane presented hydrogen permeance of 2.4 × 10-8mol·m-2·s-1·Pa-1and H2/CO2 permselectivity of 28, indicating that the membrane retains its microporous structure.展开更多
Cu（OH）2 nanowires were prepared and incorporated into poly（vinylidene fluoride）（PVDF） to fabricate Cu（OH）2-PVDF ultrafiltration（UF） membrane via immersion precipitation phase inversion process. The effect of...Cu（OH）2 nanowires were prepared and incorporated into poly（vinylidene fluoride）（PVDF） to fabricate Cu（OH）2-PVDF ultrafiltration（UF） membrane via immersion precipitation phase inversion process. The effect of Cu（OH）2 nanowires on the morphology of membranes was investigated by X-ray photoelectron spectroscopy（XPS）, Fourier transform infrared（FTIR） spectroscopy, atomic force microscopy（AFM）, scanning electron microscopy（SEM） and X-ray diffraction（XRD） measurements. The results showed that all the Cu（OH）2-PVDF membranes had wider fingerlike pore structure and better hydrophilicity, smoother surface than pristine PVDF membrane due to the incorporation of Cu（OH）2 nanowires. In addition, water flux and bovine serum albumin（BSA） rejection were also measured to investigate the filtration performance of membranes. The results indicated that all the Cu（OH）2-PVDF membranes had high water flux, outstanding BSA rejection and excellent antifouling properties. It is worth mentioning that the optimized performance could be obtained when the Cu（OH）2 nanowires content reached 1.2 wt%. Furthermore, the membrane with 1.2 wt% Cu（OH）2 nanowires showed outstanding oil-water emulsion separation capability.展开更多
Y-type zeolite membranes were synthesized by a two-step approach in which a particle seed layer was prepared by electrophoresis deposition(EPD) at first, followed by densification through secondary growth. The pre-see...Y-type zeolite membranes were synthesized by a two-step approach in which a particle seed layer was prepared by electrophoresis deposition(EPD) at first, followed by densification through secondary growth. The pre-seeding adopted the directing agent for Y-type zeolite synthesis serving as seeds. The effects of aging time of the directing agent, electrophoresis voltage and electrophoresis deposition time on seed layers quality as well as the quality of zeolite membranes were investigated. The results indicated that the zeolite seeds derived from the directing agent could be evenly deposited on substrate under certain EPD conditions. The XRD patterns of the seeded substrates after the secondary growth showed that the pure as-synthesized Y-type zeolite membranes had successfully grown on the substrates. The SEM images indicated that the substrate was covered by the highly intergrown zeolite crystals when the seeding solution employed the directing agent with an aging time of 2 days. The separation performance of zeolite membrane was evaluated using a CO_2/N2 mixture(with a mole ratio of 1:1) at different temperatures. Furthermore, the pervaporation measurements were carried out for the dehydration of isopropanol aqueous solutions with different mass fractions. The as-synthesized Y-type zeolite membranes exhibited a relatively high selectivity of water from isopropanol and sustainable permeation flux.展开更多
Sustainable processes for purifying water,capturing carbon,producing biofuels,operating fuel cells,and performing energy-efficient industrial separations will require next-generation membranes.Solvent-less fabrication...Sustainable processes for purifying water,capturing carbon,producing biofuels,operating fuel cells,and performing energy-efficient industrial separations will require next-generation membranes.Solvent-less fabrication for membranes not only eliminates potential environmental issues with organic solvents,but also solves the swelling problems that occur with delicate polymer substrates.Furthermore,the activation procedures often required for synthesizing microporous materials such as metal–organic frameworks(MOFs)can be reduced when solvent-less vapor-phase approaches are employed.This perspective covers several vacuum deposition processes,including initiated chemical vapor deposition(iCVD),initiated plasma-enhanced chemical vapor deposition(iPECVD),solvent-less vapor deposition followed by in situ polymerization(SLIP),atomic layer deposition(ALD),and molecular layer deposition(MLD).These solvent-less vapor-phase methods are powerful in creating ultrathin selective layers for thin-film composite membranes and advantageous in conformally coating nanoscale pores for the precise modification of pore size and internal functionalities.The resulting membranes have shown promising performance for gas separation,nanofiltration,desalination,and water/oil separation.Further development of novel membrane materials and the scaling up of high-throughput reactors for solvent-less vapor-phase processes are necessary in order to make a real impact on the chemical industry in the future.展开更多
Triheptyl cellulose/ethyl cellulose(3/97)binary blend membranes were prepared from tetrahydrofuran,chloroform and dichloromethane solutions and their air separation capabit- ities were studied at different temperature...Triheptyl cellulose/ethyl cellulose(3/97)binary blend membranes were prepared from tetrahydrofuran,chloroform and dichloromethane solutions and their air separation capabit- ities were studied at different temperatures.With increasing temperature from 25 to 85℃,the flux QOEA of O_2-enriched air(OEA),O_2 permselectivity and the O_2 concentration Yo_2 in the OEA all increase.The membranes show a unique trend in their Yo_2～QOEA relationship,that is,the air separation capability increases simultaneously with the OEA permeation capability.The magnitudes of QOEA and Yo_2 for 17μm-thick membrane after the testg time of 36hours at 70℃ are 5×10^(-4)cm^3 (STP)/s·cm^2 and 37.6%,respectively.The air separation capability depends slightly on membrane forming solvents.展开更多
Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-...Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-based membranes.Herein,we firstly reported the incorporation of protic ILs (PILs) having ether-rich and carboxylate sites (ECPILs) into poly(ether-block-amide)(Pebax) matrix for efficient separation H_(2)S and CO_(2)from CH_(4).Notably,the optimal permeability of H_(2)S reaches up to 4310 Barrer (40C,0.50 bar) in Pebax/ECPIL membranes,along with H_(2)S/CH_(4)and (H_(2)StCO_(2))/CH_(4)selectivity of 97.7 and 112.3,respectively.These values are increased by 1125%,160.8%and 145.9%compared to those in neat Pebax membrane.Additionally,the solubility and diffusion coefficients of the gases were measured,demonstrating that ECPIL can simultaneously strengthen the dissolution and diffusion of H_(2)S and CO_(2),thus elevating the permeability and permselectivity.By using quantum chemical calculations and FT-IR spectroscopy,the highly reversible multi-site hydrogen bonding interaction between ECPILs and H_(2)S was revealed,which is responsible for the fast permeation of H_(2)S and good selectivity.Furthermore,H_(2)S/CO_(2)/CH_(4)(3/3/94 mol/mol) ternary mixed gas can be efficiently and stably separated by Pebax/ECPIL membrane for at least 100 h.Overall,this work not only illustrates that PILs with ether-rich and carboxylate hydrogen bonding sites are outstanding materials for simultaneous removal of H_(2)S and CO_(2),but may also provide a novel insight into the design of membrane materials for natural gas upgrading.展开更多
Separating He from CH_(4)or N_(2)is crucial for natural gas He extraction,a prevailing industrial approach.Herein,molecular simulation and machine learning(ML)were combined to screen 801 experimentally synthesized COF...Separating He from CH_(4)or N_(2)is crucial for natural gas He extraction,a prevailing industrial approach.Herein,molecular simulation and machine learning(ML)were combined to screen 801 experimentally synthesized COFs for He/CH_(4)and He/N_(2)separation,either by means of adsorption or membrane separation.Top 10 COFs for 4 different gas separation purposes(CH_(4)/He or N_(2)/He separation with either adsorption or membrane)were identified respectively.The highest adsorption performance score(APSmix,defined as the product of working capacity and adsorption selectivity for mixture gas)reached 447.88 mol/kg and 49.45 mol/kg for CH_(4)/He and N_(2)/He,with corresponding adsorption selectivity of 115.56 and 30.33.He permeabilities of 1.5×10^(6)or 1.2×10^(6)Barrer were achieved for equimolar He/CH_(4)or He/N_(2)mixture gas separations,accompanied by permselectivity of 5.47 and 11.80 well surpassing 2008 Robeson's upper bound.Best performing COFs for adsorption separation are 3D COFs with pore diameter below 0.8 nm while those for membrane separation are 2D COFs with large pores.Additionally,ML models were developed to predict separation performance,with key descriptors identified.The mechanism for how COFs'structure affects their separation performance was also revealed.展开更多
基金supported by the Foundation Research Project of Kaili University(No.2025ZD007)the National Key Research and Development Program of China(No.2021YFB3801503)the Joint Research Program of Shaoxing University and Shaoxing Institute,Zhejiang University(No.2023LHLG006),China.
文摘The presence of chirality,a fundamental attribute found in nature,is of great significance in the field of pharmaceutical science.Chiral drugs are unique in that their molecular structure is non-superimposable on its mirror image.This stereoisomerism significantly impacts the functionality,metabolic pathway,effectiveness,and safety of chiral medications.The enantiomers of chiral drugs can exhibit diverse pharmacological effects in the human body.As a result,it is essential to separate and purify chiral drugs effectively.Despite the abundance of reports on chiral drug separation membranes,there is a dearth of comprehensive reviews.This paper aims to fill this gap by providing a thorough review from a materials perspective,with a focus on the design and construction of chiral drug separation membranes.Furthermore,it systematically analyzes the separation mechanisms employed by these membranes.The paper also delves into the challenges and prospects related to chiral drug separation membranes,with the intention of imparting valuable insights for further research and development in this field.
基金supported by the National Key Research and Development Program of China(2021YF B3802600)National Key Research and Development Project of China(2018YFE0203500)the Natural Science Foundation of Jiangsu Province(BK20190603).
文摘Membrane separation technology has been taken up for use in diverse applications such as water treatment,pharmaceutical,petroleum,and energy-related industries.Compared with the design of membrane materials,the innovation of membrane preparation technique is more urgent for the development of membrane separation technology,because it not only affects physicochemical properties and separation performance of the fabricated membranes,but also determines their potential in industrialized application.Among the various membrane preparation methods,spray technique has recently gained increasing attention because of its low cost,rapidity,scalability,minimum of environmental burden,and viability for nearly unlimited range of materials.In this Review article,we summarized and discussed the recent developments in separation membranes using the spray technique,including the fundamentals,important features and applications.The present challenges and future considerations have been touched to provide inspired insights for developing the sprayed separation membranes.
基金supported by the National Natural Science Foundation of China(Grant No.2230081973)Shanghai Pilot Program for Basic Research(22TQ1400100-4).
文摘Membrane technology holds significant potential for augmenting or partially substituting conventional separation techniques,such as heatdriven distillation,thereby reducing energy consumption.Organic solvent nanofiltration represents an advanced membrane separation technology capable of discerning molecules within a molecular weight range of approximately 100-1000 Da in organic solvents,offering low energy requirements and minimal carbon footprints.Molecular separation in non-polar solvent system,such as toluene,n-hexane,and n-heptane,has gained paramount importance due to their extensive use in the pharmaceutical,biochemical,and petrochemical industries.In this review,we presented recent advancements in membrane materials,membrane fabrication techniques and their promising applications for separation in nonpolar solvent system,encompassing hydrocarbon separation,bioactive molecule purification and organic solvent recovery.Furthermore,this review highlighted the challenges and opportunities associated with membrane scale-up strategies and the direct translation of this promising technology into industrial applications.
基金supported by the National Natural Science Foundation of China(No.22271022,No 22378327).
文摘Covalent organic skeletons(COFs)have been widely used in gas separation due to their excellent pore structure,high crystallinity,and high specific surface area.In this work,Dha Tab-COF was synthesized by solvothermal method and filled in polyether block polyamide(PEBAX)to form mixed matrix membranes(MMMs).Various characterization methods such as Fourier transform infrared spectroscopy(FT-IR),Xray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM)and X-ray diffractometry(XRD)were used to characterize the structure of Dha Tab-COF as well as the MMMs.The effects of operating pressure,operating temperature and the content of Dha Tab-COF particles on the CO_(2)/CH_(4)separation performance of the membranes were investigated.The best separation performance with a CO_(2)permeability of 295.8 barrer(1 barrer=7.52×10^(-18)m^(3)·(STP)·m^(-2)·m·s^(-1)·Pa^(-1))and a CO_(2)/CH_(4)selectivity of 21.6 was achieved when the Dha Tab-COF content is 2%(mass),which were 45.7%and 108.1%higher than that of the pure PEBAX membrane,respectively.
基金the Russian Science Foundation(Project 16-13-00112)the budget project#AAAA-A17-117041110045-9 for Boreskov Institute of Catalysis is gratefully acknowledged.
文摘In the field of modern hydrogen energy,obtaining pure hydrogen and syngas and then being able to use them for green energy production are significant problems.Developing solid oxide fuel cells(SOFC)and catalytic membranes for oxygen separation as well as materials for these devices is one of the most likely ways to solve these problems.In this work,the authors’recent studies in this field are reviewed;the fundamentals of developing materials for SOFC cathodes and oxygen separation membranes’permselective layers based on research of their oxygen mobility and surface reactivity are presented.Ruddlesden-Popper phases Ln_(2-x)Ca_(x)NiO_(4+δ)(LnCNO)and perovskite-fluorite nanocomposites PrNi_(0.5)Co_(0.5)O_(3-δ)-Ce_(0.9)Y_(0.1)O_(2-δ)(PNC-YDC)were studied by isotope exchange of oxygen with C_(18)O_(2)and^(18)O_(2)in flow and closed reactors.For LnCNO a high oxygen mobility was shown(D*~10^(-7)cm^(2)/s at 700℃),being provided by the cooperative mechanism of oxygen migration involving both regular and highly-mobile interstitial oxygen.For PNC-YDC dominated a wide fast diffusion channel via fluorite phase and interphases due to features of the redistribution of cations resulting in superior oxygen mobility(D*~10^(-8)cm^(2)/s at 700℃).After optimization of composition and nanodomain structure of these materials,as cathodes of SOFC they provided a high power density,while for asymmetric supported oxygen separation membranes-a high oxygen permeability.
基金Project supported by the National Natural Science Foundation of China(Nos.51828301,51773175,and 51973185)the Fundamental Research Funds for the Central Universities,China。
文摘Synthetic polymer membranes are widely used in many applications,including,among others,water purification,protein separation,and medicine.However,the use of existing polymer membranes faces major challenges,such as the trade-off between permeability and selectivity,membrane fouling,and poor mechanical strength.To address these problems the authors have focused their research on surface/interfacial tailoring and the structure-property relationship of polymer membranes used in liquid separation systems.Progress has been made as follows:(1)a methodology for membrane surface functionalization and nanofiltration(NF)membrane preparation based on mussel-inspired catecholic chemistry was proposed and established;(2)a class of mechanically robust and environmentally-responsive composite membranes with hydrogel pore-filled in rigid macroporous supports was designed and developed;(3)a methodology for surface tailoring and antifouling modification of polymer membranes based on amphiphilic copolymers was created and the scientific implications for amphiphilic polymer membranes elaborated;(4)an adsorption membrane with both filtration and adsorption functions was designed and developed to achieve rapid removal of trace micropollutants,including heavy metal ions,organic dyes,plasticizer,antibiotics,and others.This mini-review briefly summarizes this work.
基金funded by the National Key Research and Development Program of China (grant no.2019YFB1505000).
文摘Membrane separation technologies,with a broad application prospect in the field of hydrogen separation,are characterized by the simplicity of the devices,high energy efficiency and environmental friendliness.The performance of separation membranes is the primary factor that determines the efficiency of hydrogen separation.Therefore,the development of hydrogen separation membranes is always a research focus.This paper presents and reviews the research developments and features of organic membranes,inorganic membranes and hybrid matrix membranes for hydrogen separations.First,the characterization methods of key index parameters of membrane materials are presented.Second,the performance parameters of different types of membrane are compared.Finally,the trend of technological development of different types of membrane materials is forecast.
文摘Poly(ethylene-oxide)(PEO)-based membranes have attracted much attention recently for CO2 separation because CO2 is highly soluble into PEO and shows high selectivity over other gases such as CH4 and N2.Unfortunately,those membranes are not strong enough mechanically and highly crystalline,which hinders their broader applications for separation membranes.In this review discussions are made,as much in detail as possible,on the strategies to improve gas separation performance of PEO-based membranes.Some of techniques such as synthesis of graft copolymers that contain PEO,cross-linking of polymers and blending with long chains polymers contributed significantly to improvement of membrane.Incorporation of ionic liquids/nanoparticles has also been found effective.However,surface modification of nanoparticles has been done chemically or physically to enhance their compatibility with polymer matrix.As a result of all such efforts,an excellent performance,i.e.,CO2 permeability up to 200 Barrer,CO2/N2 selectivity up to 200 and CO2/CH4 selectivity up to 70,could be achieved.Another method is to introduce functional groups into PEO-based polymers which boosted CO2 permeability up to 200 Barrer with CO2/CH4 selectivity between 40 and 50.The CO2 permeability of PEO-based membranes increases,without much change in selectivity,when the length of ethylene oxide is increased.
基金Supported by the National Natural Science Foundation of China(21276123,21490581)the National High Technology Research and Development Program of China(2012AA03A606)+1 种基金the "Summit of the Six Top Talents" Program of Jiangsu Province(2011-XCL-021)the Open Research Fund Program of Collaborative Innovation Center of Membrane Separation and Water Treatment(2016YB01)
文摘A series of organosilica sols are prepared by the polymeric sol–gel method using 1,2-bis(triethoxysilyl)ethane(BTESE)as the precursor.Particle size distributions of the BTESE-derived sols are systematically investigated by carefully adjusting the synthesis parameters(i.e.,water ratios,acid ratios and solvent ratios)in the sol process.In certain conditions,increasing the water ratio or the acid ratio tends to cause larger sol sizes and bimodal particle size distributions.However,higher solvent ratios lead to smaller sol sizes and unimodal particle size distributions.The organosilica membranes prepared from the optimized sols show excellent H_2 permeances(up to 4.2×10^(-7)mol·m^(-2)·s^(-1)·Pa^(-1))and gas permselectitivies(H_2/CO_2 is 9.5,H_2/N_2 is 50 and H_2/CH_4 is 68).This study offers significant insights into the relationship between the sol synthesis parameters,sol sizes and membrane performance.
基金supported by the National High Technology Research and Development Program of China(863 Program)(No.2012AA03A611)
文摘Poly（amide-6-b-ethylene oxide）（Pebax1657）/1-butyl-3-methylimidazo-lium bis[trifluoromethyl）sulfonyl]-imide（[Bmim][Tf2N]） blend membranes with different [Bmim][Tf2N] contents were prepared via solution casting and solvent evaporation method. The permeation properties of the blend membranes for CO2, N2,CH4 and H2 were studied, and the physical properties were characterized by differential scanning calorimeter（DSC） and X-ray diffraction（XRD）. Results showed that [Bmim][Tf2N] was dispersed as amorphous phase in the blend membranes, which caused the decrease of Tg（PE） and crystallinity（PA）. With the addition of [Bmim][Tf2N], the CO2 permeability increased and reached up to approximately 286 Barrer at 40 wt%[Bmim][Tf2N], which was nearly double that of pristine Pebax1657 membrane. The increase of CO2 permeability may be attributed to high intrinsic permeability of [Bmim][Tf2N], the increase of fractional free of volume（FFV） and plasticization effect. However, the CO2 permeability reduced firstly when the [Bmim][Tf2N]content was below 10 wt%, which may be due to that the small ions of [Bmim][Tf2N] in the gap of polymer chain inhibited the flexibility of polymer chain; the interaction between Pebax1657 and [Bmim][Tf2N]decreased the content of EO units available for CO2 transport and led to a more compact structure. For Pebax1657/[Bmim][Tf2N] blend membranes, the permeabilities of N2, H2 and CH4decreased with the increase of feed pressure due to the hydrostatic pressure effect, while CO2 permeability increased with the increase of feed pressure for that the CO2-induced plasticization effect was stronger than hydrostatic pressure effect.
基金Supported by the National Basic Research Program of China(2013CB733501)the National Natural Science Foundation of China(21136004,21176112,21476106,and21428601)+1 种基金Specialized Research Fund for the Doctoral Program of Higher Education(No.20133221110001)the Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘The high price and toxicity of ionic liquids(ILs) have limited the design and application of supported ionic liquid membranes(SILMs) for CO_2 separation in both academic and industrial fields. In this work, [Choline][Pro]/polyethylene glycol 200(PEG200) mixtures were selected to prepare novel SILMs because of their green and costeffective characterization, and the CO_2/N_2 separation with the prepared SILMs was investigated experimentally at temperatures from 308.15 to 343.15 K. The temperature effect on the permeability, solubility and diffusivity of CO_2 was modeled with the Arrhenius equation. A competitive performance of the prepared SILMs was observed with high CO_2 permeability ranged in 343.3–1798.6 barrer and high CO_2/N_2 selectivity from 7.9 to 34.8.It was also found that the CO_2 permeability increased 3 times by decreasing the viscosity of liquids from 370 to38 m Pa·s. In addition, the inherent mechanism behind the significant permeability enhancement was revealed based on the diffusion-reaction theory, i.e. with the addition of PEG200, the overall resistance was substantially decreased and the SILMs process was switched from diffusion-control to reaction-control.
基金The work is supported by the National Natural Science Foundation of China(grant nos.51873067 and 21961142018)the Natural Science Foundation of Guangdong Province(grant no.2021A1515012024).
文摘Metal-organic polyhedra(MOPs)possess a microporous framework and impose hierarchical constraints on their surface ligands,leading to the long-ignored,logarithmic ligand exchange dynamics.Herein,polymer networks with MOP as nanoscale cross-linkers(MOP-CNs)can integrate unique ligand exchange dynamics and microporosity,affording vitrimer-like gas separation membranes with promising mechanical performance and(re)processability.All the ligands on the MOP surfaces are confined and correlated via a 3D coordination framework and their neighboring spaces,giving rise to a high energy barrier for ligand exchange.Therefore,MOP-CNs demonstrate high mechanical strengths at room temperature due to their negligible ligand dynamics.The thermo-activated ligand exchange process with integrated network topology enables facile(re)processing and high solvo-resistance at high temperatures.This facilitates Arrhenius type temperature dependence of flowability and stress relaxation,giving rise to the simultaneous achievement of promising mechanical strengths and(re)processability.Finally,the cage topologies of MOPs endow the materials with a bonus microporous feature and spur their applications as gas separation membranes.
基金the financial support from the National Natural Science Foundation of China(No.21436009)
文摘Mixed matrix hollow fiber membranes（MMHFMs）filled with metal-organic frameworks（MOFs）have great potential for energy-efficient gas separation processes,but the major hurdle is polymer/MOFs interfacial defects and membrane plasticization.Herein,lab-synthesized MIL-53 was post-functionalized by aminosilane grafting and subsequently incorporated into Ultem-1000 polymer matrix to fabricate high performance MMHFMs.SEM,DLS,XRD and TGA were performed to characterize silane-modified MIL-53（S-MIL-53）and prepared MMHFMs.Moreover,the effect of MOFs loading was systematically investigated first;then gas separation performance of MMHFMs for pure and mixed gas was evaluated under different pressures.MMHFMs containing post-functionalized S-MIL-53 achieved remarkable gas permeation properties which was better than model predictions.Compared to pure HFMs,CO2permeance of MMHFM loaded with 15%S-MIL-53 increased by 157%accompanying with 40%increase for CO2/N2selectivity,which outperformed the MMHFM filled with naked MIL-53.The pure and mixed gas permeation measurements with elevated feed pressure indicated that incorporation of S-MIL-53 also increased the resistance against CO2plasticization.This work reveals that post-modified MOFs embedded in MMHFMs facilitate the improvement of gas separation performance and suppression of membrane plasticization.
基金Supported by the National Natural Science Foundation of China(21276123,21490581)the National High Technology Research and Development Program of China(2012AA03A606)+3 种基金State Key Laboratory of Materials-Oriented Chemical Engineering(ZK201002)the Natural Science Research Plan of Jiangsu Universities(11KJB530006)the "Summit of the Six Top Talents" Program of Jiangsu Provincea Project Funded by the Priority Academic Program development of Jiangsu Higher Education Institutions(PAPD)
文摘A microporous zirconia membrane with hydrogen permeance about 5 × 10-8mol·m-2·s-1·Pa-1, H2/CO2 permselectivity of ca. 14, and excellent hydrothermal stability under steam pressure of 100 k Pa was fabricated via polymeric sol–gel process. The effect of calcination temperature on single gas permeance of sol–gel derived zirconia membranes was investigated. Zirconia membranes calcined at 350 °C and 400 °C showed similar single gas permeance, with permselectivities of hydrogen towards other gases, such as oxygen, nitrogen, methane, and sulfur hexa fluoride, around Knudsen values. A much lower CO2permeance（3.7 × 10-9mol·m-2·s-1·Pa-1）was observed due to the interaction between CO2 molecules and pore wall of membrane. Higher calcination temperature, 500 °C, led to the formation of mesoporous structure and, hence, the membrane lost its molecular sieving property towards hydrogen and carbon dioxide. The stability of zirconia membrane in the presence of hot steam was also investigated. Exposed to 100 k Pa steam for 400 h, the membrane performance kept unchanged in comparison with freshly prepared one, with hydrogen and carbon dioxide permeances of 4.7 × 10-8and ~ 3 × 10-9mol·m-2·s-1·Pa-1, respectively. Both H2 and CO2permeances of the zirconia membrane decreased with exposure time to 100 k Pa steam. With a total exposure time of 1250 h, the membrane presented hydrogen permeance of 2.4 × 10-8mol·m-2·s-1·Pa-1and H2/CO2 permselectivity of 28, indicating that the membrane retains its microporous structure.
基金financially supported by the Postdoctoral Science Foundation of China (No.2014M560802)the Natural Science Foundation of Education Department of Shaanxi Provincial Government (No.16JK1755)the State Key Laboratory of Chemical Engineering (No.SKL-ChE-16A04)
文摘Cu（OH）2 nanowires were prepared and incorporated into poly（vinylidene fluoride）（PVDF） to fabricate Cu（OH）2-PVDF ultrafiltration（UF） membrane via immersion precipitation phase inversion process. The effect of Cu（OH）2 nanowires on the morphology of membranes was investigated by X-ray photoelectron spectroscopy（XPS）, Fourier transform infrared（FTIR） spectroscopy, atomic force microscopy（AFM）, scanning electron microscopy（SEM） and X-ray diffraction（XRD） measurements. The results showed that all the Cu（OH）2-PVDF membranes had wider fingerlike pore structure and better hydrophilicity, smoother surface than pristine PVDF membrane due to the incorporation of Cu（OH）2 nanowires. In addition, water flux and bovine serum albumin（BSA） rejection were also measured to investigate the filtration performance of membranes. The results indicated that all the Cu（OH）2-PVDF membranes had high water flux, outstanding BSA rejection and excellent antifouling properties. It is worth mentioning that the optimized performance could be obtained when the Cu（OH）2 nanowires content reached 1.2 wt%. Furthermore, the membrane with 1.2 wt% Cu（OH）2 nanowires showed outstanding oil-water emulsion separation capability.
基金supported by the Talent Introduction Fund of Yangzhou Universitythe Jiangsu Social Development Project-Science and Technology Support Program(BE2014613)+1 种基金Six Talent Peaks of Jiangsu province(2014-XCL-013)the Project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Y-type zeolite membranes were synthesized by a two-step approach in which a particle seed layer was prepared by electrophoresis deposition(EPD) at first, followed by densification through secondary growth. The pre-seeding adopted the directing agent for Y-type zeolite synthesis serving as seeds. The effects of aging time of the directing agent, electrophoresis voltage and electrophoresis deposition time on seed layers quality as well as the quality of zeolite membranes were investigated. The results indicated that the zeolite seeds derived from the directing agent could be evenly deposited on substrate under certain EPD conditions. The XRD patterns of the seeded substrates after the secondary growth showed that the pure as-synthesized Y-type zeolite membranes had successfully grown on the substrates. The SEM images indicated that the substrate was covered by the highly intergrown zeolite crystals when the seeding solution employed the directing agent with an aging time of 2 days. The separation performance of zeolite membrane was evaluated using a CO_2/N2 mixture(with a mole ratio of 1:1) at different temperatures. Furthermore, the pervaporation measurements were carried out for the dehydration of isopropanol aqueous solutions with different mass fractions. The as-synthesized Y-type zeolite membranes exhibited a relatively high selectivity of water from isopropanol and sustainable permeation flux.
基金Zhejiang University,the research grant from the State Key Laboratory of Chemical Engineering(SKL-ChE-19T04)the funding support from the Institute of Zhejiang University-Quzhou(IZQ2019-KJ-011)Junjie Zhao also acknowledges the funding from the National Natural Science Foundation of China(21908194 and 21938011).
文摘Sustainable processes for purifying water,capturing carbon,producing biofuels,operating fuel cells,and performing energy-efficient industrial separations will require next-generation membranes.Solvent-less fabrication for membranes not only eliminates potential environmental issues with organic solvents,but also solves the swelling problems that occur with delicate polymer substrates.Furthermore,the activation procedures often required for synthesizing microporous materials such as metal–organic frameworks(MOFs)can be reduced when solvent-less vapor-phase approaches are employed.This perspective covers several vacuum deposition processes,including initiated chemical vapor deposition(iCVD),initiated plasma-enhanced chemical vapor deposition(iPECVD),solvent-less vapor deposition followed by in situ polymerization(SLIP),atomic layer deposition(ALD),and molecular layer deposition(MLD).These solvent-less vapor-phase methods are powerful in creating ultrathin selective layers for thin-film composite membranes and advantageous in conformally coating nanoscale pores for the precise modification of pore size and internal functionalities.The resulting membranes have shown promising performance for gas separation,nanofiltration,desalination,and water/oil separation.Further development of novel membrane materials and the scaling up of high-throughput reactors for solvent-less vapor-phase processes are necessary in order to make a real impact on the chemical industry in the future.
文摘Triheptyl cellulose/ethyl cellulose(3/97)binary blend membranes were prepared from tetrahydrofuran,chloroform and dichloromethane solutions and their air separation capabit- ities were studied at different temperatures.With increasing temperature from 25 to 85℃,the flux QOEA of O_2-enriched air(OEA),O_2 permselectivity and the O_2 concentration Yo_2 in the OEA all increase.The membranes show a unique trend in their Yo_2～QOEA relationship,that is,the air separation capability increases simultaneously with the OEA permeation capability.The magnitudes of QOEA and Yo_2 for 17μm-thick membrane after the testg time of 36hours at 70℃ are 5×10^(-4)cm^3 (STP)/s·cm^2 and 37.6%,respectively.The air separation capability depends slightly on membrane forming solvents.
基金sponsored by the National Natural Science Foundation of China (Nos. 22308145, 22208140, 22178159, 22078145)Natural Science Foundation of Jiangsu Province (BK20230791)Postgraduate Research Innovation Program of Jiangsu Province (KYCX24_0165)。
文摘Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-based membranes.Herein,we firstly reported the incorporation of protic ILs (PILs) having ether-rich and carboxylate sites (ECPILs) into poly(ether-block-amide)(Pebax) matrix for efficient separation H_(2)S and CO_(2)from CH_(4).Notably,the optimal permeability of H_(2)S reaches up to 4310 Barrer (40C,0.50 bar) in Pebax/ECPIL membranes,along with H_(2)S/CH_(4)and (H_(2)StCO_(2))/CH_(4)selectivity of 97.7 and 112.3,respectively.These values are increased by 1125%,160.8%and 145.9%compared to those in neat Pebax membrane.Additionally,the solubility and diffusion coefficients of the gases were measured,demonstrating that ECPIL can simultaneously strengthen the dissolution and diffusion of H_(2)S and CO_(2),thus elevating the permeability and permselectivity.By using quantum chemical calculations and FT-IR spectroscopy,the highly reversible multi-site hydrogen bonding interaction between ECPILs and H_(2)S was revealed,which is responsible for the fast permeation of H_(2)S and good selectivity.Furthermore,H_(2)S/CO_(2)/CH_(4)(3/3/94 mol/mol) ternary mixed gas can be efficiently and stably separated by Pebax/ECPIL membrane for at least 100 h.Overall,this work not only illustrates that PILs with ether-rich and carboxylate hydrogen bonding sites are outstanding materials for simultaneous removal of H_(2)S and CO_(2),but may also provide a novel insight into the design of membrane materials for natural gas upgrading.
基金the support from the Natural Science Foundation of China(U23A20115)the Natural Science Foundation of China(22368027,22078104)+4 种基金Science and Technology Key Project of Guangdong Province(2025B0101060003)the Natural Science Foundation of Guangdong Province(2024A1515012725,2024A1515012724)Guangzhou Municipal Science and Technology Project(2024A04J6251)State Key Laboratory of Pulp and Paper Engineering 2024ZD03Fundamental Research Funds for the Central Universities(2025ZYGXZR023)。
文摘Separating He from CH_(4)or N_(2)is crucial for natural gas He extraction,a prevailing industrial approach.Herein,molecular simulation and machine learning(ML)were combined to screen 801 experimentally synthesized COFs for He/CH_(4)and He/N_(2)separation,either by means of adsorption or membrane separation.Top 10 COFs for 4 different gas separation purposes(CH_(4)/He or N_(2)/He separation with either adsorption or membrane)were identified respectively.The highest adsorption performance score(APSmix,defined as the product of working capacity and adsorption selectivity for mixture gas)reached 447.88 mol/kg and 49.45 mol/kg for CH_(4)/He and N_(2)/He,with corresponding adsorption selectivity of 115.56 and 30.33.He permeabilities of 1.5×10^(6)or 1.2×10^(6)Barrer were achieved for equimolar He/CH_(4)or He/N_(2)mixture gas separations,accompanied by permselectivity of 5.47 and 11.80 well surpassing 2008 Robeson's upper bound.Best performing COFs for adsorption separation are 3D COFs with pore diameter below 0.8 nm while those for membrane separation are 2D COFs with large pores.Additionally,ML models were developed to predict separation performance,with key descriptors identified.The mechanism for how COFs'structure affects their separation performance was also revealed.
