A novel integrated film of sulfonated polysulfone/graphene/potassium copper ferricyanide(KCuFC/SPSG)was used for selectively extracting rubidium ion(Rb^(+))from brine.To form KCuFC/SPSG,the precursor film of sulfonate...A novel integrated film of sulfonated polysulfone/graphene/potassium copper ferricyanide(KCuFC/SPSG)was used for selectively extracting rubidium ion(Rb^(+))from brine.To form KCuFC/SPSG,the precursor film of sulfonated polysulfone/graphene(SPSG)was synthesized by phase conversion process,which was alternately immersed in 0.1 mol·L^(-1)CuSO_(4)/K_(4)[Fe(CN)_(6)]by in-situ adsorption coupled co-precipitation method.Various data such as nuclear magnetic resonance spectrometer,Fourier transform infrared spectroscope,X-ray photoelectron spectroscope,X-ray diffraction,scanning electron microscope,and energy dispersive spectroscopy all verified that abundant KCuFC were uniformly located on the film.The resulting KCuFC/SPSG was used in film separation system.As the solution was fed into the system,the Rb^(+)could be selectively adsorption by KCuFC/SPSG.After the saturation adsorption,0.5 mol·L^(-1)NH_(4)Cl/HCl was fed into the film cell,Rb^(+)could be quickly desorbed by ion-exchange between Rb^(+)and NH_(4)^(+)in the lattice of KCuFC.The purpose of separating and recovering Rb^(+)from the brine can be achieved after the repeated operation.The effects of pH,adsorption time,and interferential ions on the adsorption capacity of Rb^(+)were investigated by batch experiments.The adsorption behavior fits the pseudo-second order kinetic process,while KCuFC has a higher adsorption capacity(Langmuir maximum sorption 165.4 mg·g^(-1)).In addition,KCuFC/SPSG shows excellent selectivity for Rb^(+)even in complex brine systems.KCuFC/SPSG could maintain 93.5%extraction efficiency after five adsorption/desorption cycles.展开更多
Membrane fouling is one of the most important challenges faced in membrane ultrafiltration operations. The copolymers of polysulfone-graft-methyl acrylate were synthesized by homogeneous photo-initiated graft copolyme...Membrane fouling is one of the most important challenges faced in membrane ultrafiltration operations. The copolymers of polysulfone-graft-methyl acrylate were synthesized by homogeneous photo-initiated graft copolymerization. The variables affecting the degree of grafting, such as the time of UV （Ultraviolet-visible） irradiation and the concentrations of the methyl acrylate and photoinitiator, were investigated. The graft copolymer membranes were prepared by the phase inversion method. The chemical and morphological changes were characterized by attenuated total reflection-Fourier transform infrared spectroscopy （ATR/FT-IR）, scanning electron microscopy, and water contact angles measurements. Results revealed that methyl acrylate groups were present on the membranes and the graft degree of methyl acrylate had remarkable effect on the performance of membranes. Pure water contact angle on the membrane surface decreases with the increase of methyl acrylate graft degree, which indicated that the hydrophilicity of graft copolymer membranes was improved. The permeation fluxes of pure water and bovine serum albumin solution were measured to evaluate the antifouling property of graft copolymer membranes, the results of which have shown an enhancement of antifouling property for graft copolymer membranes.展开更多
Polysulfone （PSF） membranes have gained great attention in the fields of ultrafiltration, microfiltration, and thin film composite membranes for nanofiltration or reverse osmosis. For the first time, it is proposed ...Polysulfone （PSF） membranes have gained great attention in the fields of ultrafiltration, microfiltration, and thin film composite membranes for nanofiltration or reverse osmosis. For the first time, it is proposed to fabricate PSF membranes via thermally induced phase separation （TIPS） process using diphenyl sulfone （DPSO2） and polyethylene glycol （PEG） as mixed diluent. DPSO2 is chosen as a crystallizable diluent, while PEG is considered in terms of molecular weight （Mw） and dosage. We systematically investigate the interactions between PSF, DPSO2 and PEG based on the simulation calculations and solubility parameter theory. It is inferred that DPSO2 has an excellent compatibility with PSF, and the addition of PEG results in the ternary system thermodynamically less stable and then facilitates its liquid-liquid （L-L） phase separation. SEM images indicate that cellular-like pores are obvious throughout the membrane when the PEG content in the mixed diluent is 25 wt%-35 wt%. We can facilely manipulate the pore size, water flux and mechanical properties of PSF membranes with the dosage of PEG-200, the Mw of PEG or the cooling rate. The successful application of TIPS can provide a new approach for structure manipulation and performance enhancement of PSF membranes.展开更多
The stability of anion exchange membranes(AEMs)is an important feature of alkaline exchange membrane fuel cells(AEMFCs),which has been extensively studied.However it remains a real challenge due to the harsh working c...The stability of anion exchange membranes(AEMs)is an important feature of alkaline exchange membrane fuel cells(AEMFCs),which has been extensively studied.However it remains a real challenge due to the harsh working condition.Herein,we developed a novel type of polysulfone-based AEMs with three modified 1,2-dimethylbenzimidazoliums containing different substitutes at C4-and C7-position.The results showed that the introduction of the substitutes could obviously improve the dimensional and alkaline stabilities of the corresponding membranes.The swelling ratios of resultant AEMs were all lower than 10%after water immersion.The membrane with 4,7-dimethoxy-1,2-dimethylbenzimidazolium group exhibited the highest alkaline stability.Only 9.2%loss of hydroxide conductivity was observed after treating the membrane in 1 mol·L^(-1)KOH solution at 80°C for 336 h.Furthermore,the density functional theory(DFT)study on the three functional group models showed that the substitutes at C4-and C7-position affected the lowest unoccupied molecular orbital(LUMO)energies of the different 1,2-dimethylbenzimidazolium groups.展开更多
Lithium metal has been considered to be the most promising anode material for the new generation of energy-storage system.However,challenges still stand in protecting lithium metal from spontaneous reactions with elec...Lithium metal has been considered to be the most promising anode material for the new generation of energy-storage system.However,challenges still stand in protecting lithium metal from spontaneous reactions with electrolytes and preventing the dendritic propagation,both of which would lead to undesirable decrease in Coulombic efficiency.Polysulfone(PSf)membrane with high rigidity and free-volume cavities of approximately 0.3 nm was employed to provide a stable interface on the surface of anodic electrode.The isotropic channels were constructed by the interconnected and uniformly distributed free volumes in the polymer matrix,and were expected to be swelled by solvent molecules and anions of lithium salt and to allow Li+ions to pass through onto the electrode surface.As a result,dendrite-free morphology of deposited lithium was observed.The stabilized interface arose from the PSf film was verified by the promoted performances of Cu|Li cells and steady voltage polarization of Li|Li cells.The full cell with PSf coated anode exhibited excellent cyclability(85%capacity retention rate over 400 cycles at 1C)and an outstanding rate capability(117 m Ah g-1 at 5C).The beneficial performances were further verified by the EIS results.This work provides a new strategic idea to settle the dendritic problems of Li metal anodes.展开更多
Using the inner-surface of polysulfone hollow fiber ultrafiltration membranes as grafted layer, the method of gas-initiation and liquid-polymerization has been studied, which aimed to adjust the diameter of the pores ...Using the inner-surface of polysulfone hollow fiber ultrafiltration membranes as grafted layer, the method of gas-initiation and liquid-polymerization has been studied, which aimed to adjust the diameter of the pores in the membranes. The degree of polymerization varied with the changes of the parameters, such as irradiation time, monomer concentration, temperature and time of polymerization and so on. The results indicated that using benzophenone(BP) which is in a gaseous condition as photo-initiator, acrylamide as graft monomer, the polyacrylamide chain was grafted on the surface of membranes. After the surface membrane being modified, the water flux and retention altered,and thus it can be seen that the diameter of the pores in the membrane was altered. These experiments contribute to finding a new way to produce the hollow fiber membrane with the small pore size and are extraordinarily worth developing and studying.展开更多
Polysulfone(PSF) is extensively used for the production of ultrafiltration(UF) membranes thanks to its high strength,chemical stability,and good processibility.However,PSF is intrinsically hydrophobic,and hydrophilic ...Polysulfone(PSF) is extensively used for the production of ultrafiltration(UF) membranes thanks to its high strength,chemical stability,and good processibility.However,PSF is intrinsically hydrophobic,and hydrophilic modification is always required to PSF-based membranes if they are intended to be used in aqueous systems.Facile strategies to prepare hydrophilic PSF membranes are thus highly demanded.Herein we spray coat a PSF-based amphiphilic block polymer onto macroporous substrates followed by selective swelling to prepare flat-sheet PSF UF membranes.The polymer is a triblock polymer containing PSF as the majority middle block tethered with shorter block of polyethylene glycol(PEG) on both ends,that is,PEG-b-PSF-b-PEG.We use the technique of spray coa ting to homogeneously dispense diluted triblock polymer solutions on the top of macroporous supports,instantly resulting in uniform,defect-free polymer coating layers with the thickness down to ~1.2 μm.The bi-layered composite structures are then immerged in ethanol/acetone mixture to generate mesoscale pores in the coating layers following the mechanism of selective swelling-induced pore generation,thus producing composite membranes with the mesoporous triblock polymer coating as the selective layers.This facile strategy is free from additional hydrophilic modification and much smaller dosages of polymers are used compared to conventional casting methods.The pore sizes,porositie s,hydrophilicity,and consequently the separation properties of the membranes can be flexibly tuned by changing the swelling duration and the composition of the swelling bath.This strategy combining spray coating and selective swelling is upscalable for the production of highperformance PSF UF membranes.展开更多
In this study,the effects of 1-Ethyl-3-methylimidazolium tetrafluoroborate ionic liquid on CO2/CH4 separation performance of symmetric polysulfone membranes are investigated.Pure polysulfone membrane and ionic liquid-...In this study,the effects of 1-Ethyl-3-methylimidazolium tetrafluoroborate ionic liquid on CO2/CH4 separation performance of symmetric polysulfone membranes are investigated.Pure polysulfone membrane and ionic liquid-containing membranes are characterized.Field emission scanning electron microscopy(FE-SEM)is used to analyze surface morphology and thickness of the fabricated membranes.Energy dispersive spectroscopy(EDS)and elemental mapping,Fourier transform infrared(FTIR),thermal gravimetric(TGA),X-ray diffraction(XRD)and Tensile strength analyses are also conducted to characterize the prepared membrane s.CO2/CH4 separation performance of the membranes are measured twice at 0.3 MPa and room temperature(250 C).Permeability measurements confirm that increasing ionic liquid content in polymer-ionic liquid membranes leads to a growth in CO2 permeation and CO2/CH4 selectivity due to high affinity of the ionic liquid to carbon dioxide.CO2 permeation significantly increases from 4,3 Barrer(1 Barrer=10^-10 cm^3(STP)·cm·m^-2·s^-1·cmHg^-1,1 cmHg=1.333 kPa)for the pure polymer membrane to 601.9 Barrer for the 30 wt%ionic liquid membrane.Also,selectivity of this membrane is improved from 8.2 to 25.8.mixed gas te sts are implemented to investigate gases interaction.The results showed,the disruptive effect of CH4 molecules for CO2 permeation lead to selectivity decrement compare to pure gas te st.The fabricated membranes with high ionic liquid content in this study are promising materials for industrial CO2/CH4 separation membranes.展开更多
Polysulfone(PS)hollow-fiber ultrafiltration membrane was characterized combined with flux and streaming potential in single electrolyte solutions.The effects of trans-membrane pressure,electrolyte concentration,ion va...Polysulfone(PS)hollow-fiber ultrafiltration membrane was characterized combined with flux and streaming potential in single electrolyte solutions.The effects of trans-membrane pressure,electrolyte concentration,ion valence and pH value of electrolyte solution on the streaming potential(SP)of the membrane were investigated.The zeta potential and surface charge density of the membrane were calculated on the basis of Helmholtz-Smoluchowski equation and Gouy-Chapmann theory.The results indicate that the valence and concentration of cation have a greater influence on the SP and surface charge density of PS membrane than those of anion,and the pH value of electrolyte solution has great effects on the SP and zeta potential of the membrane surface. Both the absolute value of the streaming potential and water flux of the adsorbed membrane decrease,compared with those of the clean membrane.The streaming potential and flux of the cleaned membrane can be completely recovered by cleaning with the mass fraction of 0.8%EDTA at pH=10.展开更多
The past few decades have witnessed rapid gains in our demands of antifouling membranes such as water purification membranes and hemodialysis membranes.A variety of methodologies have been proposed for improving the a...The past few decades have witnessed rapid gains in our demands of antifouling membranes such as water purification membranes and hemodialysis membranes.A variety of methodologies have been proposed for improving the antifouling performance and the hemocompatibility of the membranes.In this study,a series of copolymers(PSF-PESSB)containing polysulfone(PSF)and poly(arylene ether sulfone)bearing pendant zwitterionic sulfobetaine groups(PESSB)were prepared via one-pot polycondensation.Subsequently,the ultrafiltration(UF)membranes were prepared from different zwitterion-containing copolymers.The prepared membranes showed high thermal stability and mechanical properties.Besides,it also displayed attractive antifouling performance and blood compatibility.Compared with the original PSF membrane,the amount of protein absorption on the modified membrane was reduced;the flux recovery ratio and the resistance to blood cells were significantly improved.The results of this work suggest that PSF-PESSB membranes are expected to be applied in blood purification.The introduction of zwitterion-containing polymers to membranes paves ways for developing advanced hemodialysis technologies for crucial process.展开更多
Polysulfone (PSF) membranes are frequently used in ultrafiltration, due totheirchemical and structural stability and mechanical robustness. Despite these advantages, successful utilization of this membrane technology ...Polysulfone (PSF) membranes are frequently used in ultrafiltration, due totheirchemical and structural stability and mechanical robustness. Despite these advantages, successful utilization of this membrane technology has been greatly limited by the susceptibility of these membranes to fouling, due totheirhydrophobic nature. Here we report on the synthesis and characterisation of hydrophilic PSF membrane materials prepared by incorporation of polyvinyl alcohol, through chemical crosslinking to produce mechanically and chemically stable PSF hydrogels. The hydrogel composition was controlled at three different ratios to evaluate the effect of the PSF contributioni.e.25:75, 50:50 and 75:25. PSF hydrogels were characterized using high resolution scanningelectronmicroscopy (HR-SEM), cyclicvoltammetry (CV), and drop shape analysis techniques. The polysulfone hydrogels formed showed a decrease in contact angle by 50% for all hydrogels regardless of their polysulfone contribution, confirming an improvement in hydrophilic nature. The electron diffusion and ionic transport properties of thehydrogels as immobilised thin films in aqueous solutions,wereevaluated using cyclic voltammetry.展开更多
In order to improve the purification properties of polysulfone (PSF) ultrafiltration membranes (UFM), nano-graphene oxide (nano-GO) was taken as modifier, and the physical blending process was adopted in our experimen...In order to improve the purification properties of polysulfone (PSF) ultrafiltration membranes (UFM), nano-graphene oxide (nano-GO) was taken as modifier, and the physical blending process was adopted in our experiment. The microstructure, surface morphology and functional groups of modified UFM have been characterized respectively by scanning electron microscopy, atomic force microscopy and Fourier transform infrared spectroscopy, and the static contact angle between the membrane surface and the water droplet has also been detected to show the change of its hydrophilicity. Through experiments, it has been found that modified UFM has larger and more developed finger micro-pores, and there exist a large number of -OH groups on its surface, and also its hydrophilicity has been enhanced. The result of the experiments show that the modified UFM may keep rejection above 97% and its water flux can be reached at about 219.1 L/(m2·h) under pressure of 1 bar if 0.4 wt% of nano-GO was added. Additionally, the nano-GO can increase the flux recovery radio (FRR) of the membranes, and the maximum FRR was observed as 74.4% if 0.3 wt% of nano-GO was appended.展开更多
Synthetic membranes have gained an important place in chemical technology and are used in a broad range of applications. UV irradiation is an age old process used for disinfection as well as for sterilization purposes...Synthetic membranes have gained an important place in chemical technology and are used in a broad range of applications. UV irradiation is an age old process used for disinfection as well as for sterilization purposes. It is used for sterilizing equipment in which polysulfone (PSf) membranes are used. As a result, short time UV irradiation of polymer membranes has acquired importance in recent times. In the present study, microporous polysulfone membranes with0.108 mmthickness have been prepared using phase inversion method. Effect of UV irradiation on the membranes for short time intervals (0 - 60 minutes) has been investigated using UV-Vis and FTIR spectrophotometer, and SEM. The performance of the membranes has studied by filtration techniques. UV-Vis and IR spectra analysis and SEM images obtained suggest that chains scission and crosslink have occurred simultaneously in the irradiated membranes by UV radiation in a dose dependant manner. The pure water flux (PWF) values of irradiated membranes obtained from filtration studies were higher compared to that of the control membrane. These results show that a very short UV irradiation (2 minutes) affected the physicochemical characteristics of microporous polysulfone membrane which it increases with increase in time.展开更多
In this work, polysulfone/polyimide（PSf/PI） mixed matrix membranes were fabricated by reinforcement of modified zeolite（MZ） particles through solution casting method for investigation of antibacterial activity aga...In this work, polysulfone/polyimide（PSf/PI） mixed matrix membranes were fabricated by reinforcement of modified zeolite（MZ） particles through solution casting method for investigation of antibacterial activity against two gram negative bacteria（Salmonella typhi, Klebsella pneumonia） and two gram positive bacteria（Staphylococcus aureus, Bacillus subtilis）. The modified zeolite particles were incorporated to PSf and PI matrix and the influence of these particles on thermal, mechanical and structural properties was evaluated. The morphological evolution was investigated through scanning electron microscopy（SEM） and transmission electron microscopy（TEM） analysis, which revealed good compatibility between organic polymer matrix and inorganic filler. Mechanical stability was investigated by tensile testing while thermal analysis was evaluated by thermogravimetric analysis（TGA） and differential scanning calorimetry（DSC）. This revealed improvement in thermal properties with increasing filler concentration from 1 wt% to 10 wt%. Structural analysis was successfully done using X-ray diffraction analysis（XRD） and Fourier transform infrared（FTIR） spectroscopy. Solvent content of fabricated mixed matrix membranes was observed to decrease while moving from more hydrophilic to less hydrophilic solvent. However, addition of filler content enhanced the porosity of fabricated membranes. The synthesized mixed matrix membranes exhibited good antibacterial activity and the highest activity was shown by PSf/PI/MZ mixed matrix membrane. Therefore, the combination effect of PSf, PI and MZ sufficiently enhanced the antibacterial activity of mixed matrix membranes.展开更多
1 INTRODUCTIONSince the invention of asymmetric membrane by Loeb and Sourirajan [1],membraneseparation processes have attracted considerable commercial interests.L-S membranesare generally prepared by phase inversion ...1 INTRODUCTIONSince the invention of asymmetric membrane by Loeb and Sourirajan [1],membraneseparation processes have attracted considerable commercial interests.L-S membranesare generally prepared by phase inversion techniques [2].The thermodynamic and kine-tic analyses of these processes could be expressed by means of semiempiricalmathematical models.Such thermodynamic work involves the construction of a com-plete phase diagram for the membrane formation system and the membrane structure.展开更多
Organoclay-modified hydroxylterminated polysulfone (PSF)/epoxy interpenetrating network nanocomposites (oM-PSF/EP nanocomposites) were prepared by adding organophilic montmorillonite (oMMT) to interpenetrating polymer...Organoclay-modified hydroxylterminated polysulfone (PSF)/epoxy interpenetrating network nanocomposites (oM-PSF/EP nanocomposites) were prepared by adding organophilic montmorillonite (oMMT) to interpenetrating polymer networks (IPNs) of polysulfone and epoxy resin (PSF/EP) using diaminodiphenylmethane (DDM) as curing agent.The mechanical properties like tensile strength,tensile modulus,flexural strength,flexural modulus and impact properties of the nanocomposites were studied as per ASTM standards.Different...展开更多
A blending chelate filter membrane with high chelate capacity for Ag + has been prepared by blending of phosphoramidic acid resin and polysulfone. The major parameters influencing structure of the chelate filter membr...A blending chelate filter membrane with high chelate capacity for Ag + has been prepared by blending of phosphoramidic acid resin and polysulfone. The major parameters influencing structure of the chelate filter membranes such as the blending ratio, phosphoramidic acid resin grain size and temperature of casting solution have been studied. The relationship among the chelate amount of Ag +, pH value, Ag + concentration and phosphoramidic acid resin grain diameter were examined. The chelate filter membrane had a capacity of 1 438 μg/cm 2 for Ag + under appropriate conditions. Sorption isotherm of Ag + could be expressed with the Freundlich sorption model. The dynamic chelate experiments proved that the sorption and desorption of membranes could be realized simultaneously for Ag +.展开更多
Four series of copolyesters were synthesized by direct polycondonsation reaction between aromatic dicarboxylic acids and bisphenols by using tosyi chloride and N, N-dimethylformamide ( DMF ) in pyridine under mild con...Four series of copolyesters were synthesized by direct polycondonsation reaction between aromatic dicarboxylic acids and bisphenols by using tosyi chloride and N, N-dimethylformamide ( DMF ) in pyridine under mild conditions. The electron-rich hydroxyl groups of bisphenols favoured the polycondensation reaction and the order of relative reactivities of bisphenols is as follow:bisphenoI-A> hydroquinone ～ bisphenol-S> chlorohydroquinone. The mesomorphic properties of copolyesters were examined by birefringence under polarizing microscope, melt transparency. DSC and X-ray diffraction. The minimum molar fraction of mesogenic units needed for the appearance of liquid crystallinity is not higher than 0. 1 despite of the different varieties and lengths of the spacers studied.展开更多
Using polysulfone （PSF） hollow fiber ultrafiltration membranes as the substrate, sodium alginate （SA） and polyvinyl alcohol （PVA） blend solutions as the coating solution, and maleic anhydride （MAC） as the cros...Using polysulfone （PSF） hollow fiber ultrafiltration membranes as the substrate, sodium alginate （SA） and polyvinyl alcohol （PVA） blend solutions as the coating solution, and maleic anhydride （MAC） as the cross-linked agent, SAPVA/PSF hollow fiber composite membranes were prepared for the dehydration of ethanol-water. The effects of different sodium alginate concentration in the coating solutions and different operating temperatures on pervaporation performance were investigated. The experimental results showed that pervaporation performance of the SA-PVA/PSF composite membranes for ethanol-water solution exhibited a high separation factor although they had a relatively low permeation flux. As SA concentration in SA-PVA coating solution was 66.7% and the operating temperature was 40 ℃, SA-PVA/PSF hollow fiber composite membrane （PS4） had a separation factor of 886 and flux of 12.6 g/（m^2·h）. Besides, SA-PVA/PSF hollow fiber composite membranes （PS3 and PS4） were used for the investigation of the effect of ethanol concentration in the feed solution on pervaporation performance.展开更多
Several kinds of chloromethyl polysulfones （CMPF） with different chlorinity and reactive groups were synthesized by Friedel.crafts reaction, which could be utilized as reactively matrix membrane materials. The CMPF ...Several kinds of chloromethyl polysulfones （CMPF） with different chlorinity and reactive groups were synthesized by Friedel.crafts reaction, which could be utilized as reactively matrix membrane materials. The CMPF hollow matrix membranes were prepared with phase inversion by utilization of CMPF/additive/DMAC casting solution and CMPF as membrane materials. It was found that the effects of additive content, bore liquid and dry spinning distance on the structure of CMPF hollow fiber matrix membrane were different. A high qualified palysulfone hollow fiber chelating membrane modified with thiourea as chelating groups was prepared using CMPF as membrane matrix materials, through the reaction between thiourea and CMPF hollow fiber matrix membrane to afford the methyl iso-thiourium polysulfone. The experimental results showed that thermal drawing could increase the mechanical properties of matrix membrane, and the thermal treatment could increase the homogeneity and stability of the structure of polysulfoue hollow fiber chelating membrane modified with thiourea.展开更多
基金supported by the Ministry of Science and Technology of China(Science and Technology to Boost Economy 2020 Key Project,SQ2020YFF0412719 and SQ2020YFF0404901)The Key Research and Development and Transformation Program Funding in Qinghai Province(2021-GX-105)Major projects of Anhui Province and Anhui Province Key Research and Development Plan(202104e11020005)。
文摘A novel integrated film of sulfonated polysulfone/graphene/potassium copper ferricyanide(KCuFC/SPSG)was used for selectively extracting rubidium ion(Rb^(+))from brine.To form KCuFC/SPSG,the precursor film of sulfonated polysulfone/graphene(SPSG)was synthesized by phase conversion process,which was alternately immersed in 0.1 mol·L^(-1)CuSO_(4)/K_(4)[Fe(CN)_(6)]by in-situ adsorption coupled co-precipitation method.Various data such as nuclear magnetic resonance spectrometer,Fourier transform infrared spectroscope,X-ray photoelectron spectroscope,X-ray diffraction,scanning electron microscope,and energy dispersive spectroscopy all verified that abundant KCuFC were uniformly located on the film.The resulting KCuFC/SPSG was used in film separation system.As the solution was fed into the system,the Rb^(+)could be selectively adsorption by KCuFC/SPSG.After the saturation adsorption,0.5 mol·L^(-1)NH_(4)Cl/HCl was fed into the film cell,Rb^(+)could be quickly desorbed by ion-exchange between Rb^(+)and NH_(4)^(+)in the lattice of KCuFC.The purpose of separating and recovering Rb^(+)from the brine can be achieved after the repeated operation.The effects of pH,adsorption time,and interferential ions on the adsorption capacity of Rb^(+)were investigated by batch experiments.The adsorption behavior fits the pseudo-second order kinetic process,while KCuFC has a higher adsorption capacity(Langmuir maximum sorption 165.4 mg·g^(-1)).In addition,KCuFC/SPSG shows excellent selectivity for Rb^(+)even in complex brine systems.KCuFC/SPSG could maintain 93.5%extraction efficiency after five adsorption/desorption cycles.
文摘Membrane fouling is one of the most important challenges faced in membrane ultrafiltration operations. The copolymers of polysulfone-graft-methyl acrylate were synthesized by homogeneous photo-initiated graft copolymerization. The variables affecting the degree of grafting, such as the time of UV （Ultraviolet-visible） irradiation and the concentrations of the methyl acrylate and photoinitiator, were investigated. The graft copolymer membranes were prepared by the phase inversion method. The chemical and morphological changes were characterized by attenuated total reflection-Fourier transform infrared spectroscopy （ATR/FT-IR）, scanning electron microscopy, and water contact angles measurements. Results revealed that methyl acrylate groups were present on the membranes and the graft degree of methyl acrylate had remarkable effect on the performance of membranes. Pure water contact angle on the membrane surface decreases with the increase of methyl acrylate graft degree, which indicated that the hydrophilicity of graft copolymer membranes was improved. The permeation fluxes of pure water and bovine serum albumin solution were measured to evaluate the antifouling property of graft copolymer membranes, the results of which have shown an enhancement of antifouling property for graft copolymer membranes.
基金supported by the National Natural Science Foundation of China(Nos.21174124 and 21534009)
文摘Polysulfone （PSF） membranes have gained great attention in the fields of ultrafiltration, microfiltration, and thin film composite membranes for nanofiltration or reverse osmosis. For the first time, it is proposed to fabricate PSF membranes via thermally induced phase separation （TIPS） process using diphenyl sulfone （DPSO2） and polyethylene glycol （PEG） as mixed diluent. DPSO2 is chosen as a crystallizable diluent, while PEG is considered in terms of molecular weight （Mw） and dosage. We systematically investigate the interactions between PSF, DPSO2 and PEG based on the simulation calculations and solubility parameter theory. It is inferred that DPSO2 has an excellent compatibility with PSF, and the addition of PEG results in the ternary system thermodynamically less stable and then facilitates its liquid-liquid （L-L） phase separation. SEM images indicate that cellular-like pores are obvious throughout the membrane when the PEG content in the mixed diluent is 25 wt%-35 wt%. We can facilely manipulate the pore size, water flux and mechanical properties of PSF membranes with the dosage of PEG-200, the Mw of PEG or the cooling rate. The successful application of TIPS can provide a new approach for structure manipulation and performance enhancement of PSF membranes.
基金financially supported by the National Natural Science Foundation of China(No.21404018)Fundamental Research Funds for the Central Universities(No.DUT16RC(4)79)+2 种基金Education Department of the Liaoning Province(No.LT2015007)Fundamental Research Funds for the Central Universities(No.DUT16TD19)Chang Jiang Scholar Program(No.T2012049)
文摘The stability of anion exchange membranes(AEMs)is an important feature of alkaline exchange membrane fuel cells(AEMFCs),which has been extensively studied.However it remains a real challenge due to the harsh working condition.Herein,we developed a novel type of polysulfone-based AEMs with three modified 1,2-dimethylbenzimidazoliums containing different substitutes at C4-and C7-position.The results showed that the introduction of the substitutes could obviously improve the dimensional and alkaline stabilities of the corresponding membranes.The swelling ratios of resultant AEMs were all lower than 10%after water immersion.The membrane with 4,7-dimethoxy-1,2-dimethylbenzimidazolium group exhibited the highest alkaline stability.Only 9.2%loss of hydroxide conductivity was observed after treating the membrane in 1 mol·L^(-1)KOH solution at 80°C for 336 h.Furthermore,the density functional theory(DFT)study on the three functional group models showed that the substitutes at C4-and C7-position affected the lowest unoccupied molecular orbital(LUMO)energies of the different 1,2-dimethylbenzimidazolium groups.
基金supported by the Opening Project(SKLACPS-C-21)of the State Key Laboratory of Advanced Chemical Power Source,Guizhou Meiling Power Sources Co.Ltd.the Program for Innovative and Entrepreneurial team in Zhuhai(ZH01110405160007PWC)Key Laboratory of Advanced Chemical Power Sources,Guizhou Meiling Power Sources Co.Ltd.,Zunyi 563003,Guizhou,China,for funding the experiments.
文摘Lithium metal has been considered to be the most promising anode material for the new generation of energy-storage system.However,challenges still stand in protecting lithium metal from spontaneous reactions with electrolytes and preventing the dendritic propagation,both of which would lead to undesirable decrease in Coulombic efficiency.Polysulfone(PSf)membrane with high rigidity and free-volume cavities of approximately 0.3 nm was employed to provide a stable interface on the surface of anodic electrode.The isotropic channels were constructed by the interconnected and uniformly distributed free volumes in the polymer matrix,and were expected to be swelled by solvent molecules and anions of lithium salt and to allow Li+ions to pass through onto the electrode surface.As a result,dendrite-free morphology of deposited lithium was observed.The stabilized interface arose from the PSf film was verified by the promoted performances of Cu|Li cells and steady voltage polarization of Li|Li cells.The full cell with PSf coated anode exhibited excellent cyclability(85%capacity retention rate over 400 cycles at 1C)and an outstanding rate capability(117 m Ah g-1 at 5C).The beneficial performances were further verified by the EIS results.This work provides a new strategic idea to settle the dendritic problems of Li metal anodes.
基金The Natural Science Foundation of Beijing(No. 2021002) the National Basic Research Priorties Programme(No. 2003CCA02500)
文摘Using the inner-surface of polysulfone hollow fiber ultrafiltration membranes as grafted layer, the method of gas-initiation and liquid-polymerization has been studied, which aimed to adjust the diameter of the pores in the membranes. The degree of polymerization varied with the changes of the parameters, such as irradiation time, monomer concentration, temperature and time of polymerization and so on. The results indicated that using benzophenone(BP) which is in a gaseous condition as photo-initiator, acrylamide as graft monomer, the polyacrylamide chain was grafted on the surface of membranes. After the surface membrane being modified, the water flux and retention altered,and thus it can be seen that the diameter of the pores in the membrane was altered. These experiments contribute to finding a new way to produce the hollow fiber membrane with the small pore size and are extraordinarily worth developing and studying.
基金Financial support from the National Natural Science Foundation of China (21706119)the Program of Excellent Innovation Teams of Jiangsu Higher Education Institutions+1 种基金the Project of Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)the partial support by the Open Fund of State Key Laboratory of Separation Membranes and Membrane Process (M1-201702)。
文摘Polysulfone(PSF) is extensively used for the production of ultrafiltration(UF) membranes thanks to its high strength,chemical stability,and good processibility.However,PSF is intrinsically hydrophobic,and hydrophilic modification is always required to PSF-based membranes if they are intended to be used in aqueous systems.Facile strategies to prepare hydrophilic PSF membranes are thus highly demanded.Herein we spray coat a PSF-based amphiphilic block polymer onto macroporous substrates followed by selective swelling to prepare flat-sheet PSF UF membranes.The polymer is a triblock polymer containing PSF as the majority middle block tethered with shorter block of polyethylene glycol(PEG) on both ends,that is,PEG-b-PSF-b-PEG.We use the technique of spray coa ting to homogeneously dispense diluted triblock polymer solutions on the top of macroporous supports,instantly resulting in uniform,defect-free polymer coating layers with the thickness down to ~1.2 μm.The bi-layered composite structures are then immerged in ethanol/acetone mixture to generate mesoscale pores in the coating layers following the mechanism of selective swelling-induced pore generation,thus producing composite membranes with the mesoporous triblock polymer coating as the selective layers.This facile strategy is free from additional hydrophilic modification and much smaller dosages of polymers are used compared to conventional casting methods.The pore sizes,porositie s,hydrophilicity,and consequently the separation properties of the membranes can be flexibly tuned by changing the swelling duration and the composition of the swelling bath.This strategy combining spray coating and selective swelling is upscalable for the production of highperformance PSF UF membranes.
文摘In this study,the effects of 1-Ethyl-3-methylimidazolium tetrafluoroborate ionic liquid on CO2/CH4 separation performance of symmetric polysulfone membranes are investigated.Pure polysulfone membrane and ionic liquid-containing membranes are characterized.Field emission scanning electron microscopy(FE-SEM)is used to analyze surface morphology and thickness of the fabricated membranes.Energy dispersive spectroscopy(EDS)and elemental mapping,Fourier transform infrared(FTIR),thermal gravimetric(TGA),X-ray diffraction(XRD)and Tensile strength analyses are also conducted to characterize the prepared membrane s.CO2/CH4 separation performance of the membranes are measured twice at 0.3 MPa and room temperature(250 C).Permeability measurements confirm that increasing ionic liquid content in polymer-ionic liquid membranes leads to a growth in CO2 permeation and CO2/CH4 selectivity due to high affinity of the ionic liquid to carbon dioxide.CO2 permeation significantly increases from 4,3 Barrer(1 Barrer=10^-10 cm^3(STP)·cm·m^-2·s^-1·cmHg^-1,1 cmHg=1.333 kPa)for the pure polymer membrane to 601.9 Barrer for the 30 wt%ionic liquid membrane.Also,selectivity of this membrane is improved from 8.2 to 25.8.mixed gas te sts are implemented to investigate gases interaction.The results showed,the disruptive effect of CH4 molecules for CO2 permeation lead to selectivity decrement compare to pure gas te st.The fabricated membranes with high ionic liquid content in this study are promising materials for industrial CO2/CH4 separation membranes.
基金Project(20776161)supported by the National Natural Science Foundation of China
文摘Polysulfone(PS)hollow-fiber ultrafiltration membrane was characterized combined with flux and streaming potential in single electrolyte solutions.The effects of trans-membrane pressure,electrolyte concentration,ion valence and pH value of electrolyte solution on the streaming potential(SP)of the membrane were investigated.The zeta potential and surface charge density of the membrane were calculated on the basis of Helmholtz-Smoluchowski equation and Gouy-Chapmann theory.The results indicate that the valence and concentration of cation have a greater influence on the SP and surface charge density of PS membrane than those of anion,and the pH value of electrolyte solution has great effects on the SP and zeta potential of the membrane surface. Both the absolute value of the streaming potential and water flux of the adsorbed membrane decrease,compared with those of the clean membrane.The streaming potential and flux of the cleaned membrane can be completely recovered by cleaning with the mass fraction of 0.8%EDTA at pH=10.
基金financially supported by the National Natural Science Foundation of China(52003266,21961160739)the Development of Scientific and Technological Project of the Jilin Province(YDZJ202101ZYTS162,20200801051GH)Chinese Academy of Sciences-Wego Group High-tech Research&Development。
文摘The past few decades have witnessed rapid gains in our demands of antifouling membranes such as water purification membranes and hemodialysis membranes.A variety of methodologies have been proposed for improving the antifouling performance and the hemocompatibility of the membranes.In this study,a series of copolymers(PSF-PESSB)containing polysulfone(PSF)and poly(arylene ether sulfone)bearing pendant zwitterionic sulfobetaine groups(PESSB)were prepared via one-pot polycondensation.Subsequently,the ultrafiltration(UF)membranes were prepared from different zwitterion-containing copolymers.The prepared membranes showed high thermal stability and mechanical properties.Besides,it also displayed attractive antifouling performance and blood compatibility.Compared with the original PSF membrane,the amount of protein absorption on the modified membrane was reduced;the flux recovery ratio and the resistance to blood cells were significantly improved.The results of this work suggest that PSF-PESSB membranes are expected to be applied in blood purification.The introduction of zwitterion-containing polymers to membranes paves ways for developing advanced hemodialysis technologies for crucial process.
文摘Polysulfone (PSF) membranes are frequently used in ultrafiltration, due totheirchemical and structural stability and mechanical robustness. Despite these advantages, successful utilization of this membrane technology has been greatly limited by the susceptibility of these membranes to fouling, due totheirhydrophobic nature. Here we report on the synthesis and characterisation of hydrophilic PSF membrane materials prepared by incorporation of polyvinyl alcohol, through chemical crosslinking to produce mechanically and chemically stable PSF hydrogels. The hydrogel composition was controlled at three different ratios to evaluate the effect of the PSF contributioni.e.25:75, 50:50 and 75:25. PSF hydrogels were characterized using high resolution scanningelectronmicroscopy (HR-SEM), cyclicvoltammetry (CV), and drop shape analysis techniques. The polysulfone hydrogels formed showed a decrease in contact angle by 50% for all hydrogels regardless of their polysulfone contribution, confirming an improvement in hydrophilic nature. The electron diffusion and ionic transport properties of thehydrogels as immobilised thin films in aqueous solutions,wereevaluated using cyclic voltammetry.
文摘In order to improve the purification properties of polysulfone (PSF) ultrafiltration membranes (UFM), nano-graphene oxide (nano-GO) was taken as modifier, and the physical blending process was adopted in our experiment. The microstructure, surface morphology and functional groups of modified UFM have been characterized respectively by scanning electron microscopy, atomic force microscopy and Fourier transform infrared spectroscopy, and the static contact angle between the membrane surface and the water droplet has also been detected to show the change of its hydrophilicity. Through experiments, it has been found that modified UFM has larger and more developed finger micro-pores, and there exist a large number of -OH groups on its surface, and also its hydrophilicity has been enhanced. The result of the experiments show that the modified UFM may keep rejection above 97% and its water flux can be reached at about 219.1 L/(m2·h) under pressure of 1 bar if 0.4 wt% of nano-GO was added. Additionally, the nano-GO can increase the flux recovery radio (FRR) of the membranes, and the maximum FRR was observed as 74.4% if 0.3 wt% of nano-GO was appended.
文摘Synthetic membranes have gained an important place in chemical technology and are used in a broad range of applications. UV irradiation is an age old process used for disinfection as well as for sterilization purposes. It is used for sterilizing equipment in which polysulfone (PSf) membranes are used. As a result, short time UV irradiation of polymer membranes has acquired importance in recent times. In the present study, microporous polysulfone membranes with0.108 mmthickness have been prepared using phase inversion method. Effect of UV irradiation on the membranes for short time intervals (0 - 60 minutes) has been investigated using UV-Vis and FTIR spectrophotometer, and SEM. The performance of the membranes has studied by filtration techniques. UV-Vis and IR spectra analysis and SEM images obtained suggest that chains scission and crosslink have occurred simultaneously in the irradiated membranes by UV radiation in a dose dependant manner. The pure water flux (PWF) values of irradiated membranes obtained from filtration studies were higher compared to that of the control membrane. These results show that a very short UV irradiation (2 minutes) affected the physicochemical characteristics of microporous polysulfone membrane which it increases with increase in time.
文摘In this work, polysulfone/polyimide（PSf/PI） mixed matrix membranes were fabricated by reinforcement of modified zeolite（MZ） particles through solution casting method for investigation of antibacterial activity against two gram negative bacteria（Salmonella typhi, Klebsella pneumonia） and two gram positive bacteria（Staphylococcus aureus, Bacillus subtilis）. The modified zeolite particles were incorporated to PSf and PI matrix and the influence of these particles on thermal, mechanical and structural properties was evaluated. The morphological evolution was investigated through scanning electron microscopy（SEM） and transmission electron microscopy（TEM） analysis, which revealed good compatibility between organic polymer matrix and inorganic filler. Mechanical stability was investigated by tensile testing while thermal analysis was evaluated by thermogravimetric analysis（TGA） and differential scanning calorimetry（DSC）. This revealed improvement in thermal properties with increasing filler concentration from 1 wt% to 10 wt%. Structural analysis was successfully done using X-ray diffraction analysis（XRD） and Fourier transform infrared（FTIR） spectroscopy. Solvent content of fabricated mixed matrix membranes was observed to decrease while moving from more hydrophilic to less hydrophilic solvent. However, addition of filler content enhanced the porosity of fabricated membranes. The synthesized mixed matrix membranes exhibited good antibacterial activity and the highest activity was shown by PSf/PI/MZ mixed matrix membrane. Therefore, the combination effect of PSf, PI and MZ sufficiently enhanced the antibacterial activity of mixed matrix membranes.
文摘1 INTRODUCTIONSince the invention of asymmetric membrane by Loeb and Sourirajan [1],membraneseparation processes have attracted considerable commercial interests.L-S membranesare generally prepared by phase inversion techniques [2].The thermodynamic and kine-tic analyses of these processes could be expressed by means of semiempiricalmathematical models.Such thermodynamic work involves the construction of a com-plete phase diagram for the membrane formation system and the membrane structure.
文摘Organoclay-modified hydroxylterminated polysulfone (PSF)/epoxy interpenetrating network nanocomposites (oM-PSF/EP nanocomposites) were prepared by adding organophilic montmorillonite (oMMT) to interpenetrating polymer networks (IPNs) of polysulfone and epoxy resin (PSF/EP) using diaminodiphenylmethane (DDM) as curing agent.The mechanical properties like tensile strength,tensile modulus,flexural strength,flexural modulus and impact properties of the nanocomposites were studied as per ASTM standards.Different...
文摘A blending chelate filter membrane with high chelate capacity for Ag + has been prepared by blending of phosphoramidic acid resin and polysulfone. The major parameters influencing structure of the chelate filter membranes such as the blending ratio, phosphoramidic acid resin grain size and temperature of casting solution have been studied. The relationship among the chelate amount of Ag +, pH value, Ag + concentration and phosphoramidic acid resin grain diameter were examined. The chelate filter membrane had a capacity of 1 438 μg/cm 2 for Ag + under appropriate conditions. Sorption isotherm of Ag + could be expressed with the Freundlich sorption model. The dynamic chelate experiments proved that the sorption and desorption of membranes could be realized simultaneously for Ag +.
文摘Four series of copolyesters were synthesized by direct polycondonsation reaction between aromatic dicarboxylic acids and bisphenols by using tosyi chloride and N, N-dimethylformamide ( DMF ) in pyridine under mild conditions. The electron-rich hydroxyl groups of bisphenols favoured the polycondensation reaction and the order of relative reactivities of bisphenols is as follow:bisphenoI-A> hydroquinone ～ bisphenol-S> chlorohydroquinone. The mesomorphic properties of copolyesters were examined by birefringence under polarizing microscope, melt transparency. DSC and X-ray diffraction. The minimum molar fraction of mesogenic units needed for the appearance of liquid crystallinity is not higher than 0. 1 despite of the different varieties and lengths of the spacers studied.
基金Project supported by the National Basic Research Program of China (Grant No.2003CB615705)
文摘Using polysulfone （PSF） hollow fiber ultrafiltration membranes as the substrate, sodium alginate （SA） and polyvinyl alcohol （PVA） blend solutions as the coating solution, and maleic anhydride （MAC） as the cross-linked agent, SAPVA/PSF hollow fiber composite membranes were prepared for the dehydration of ethanol-water. The effects of different sodium alginate concentration in the coating solutions and different operating temperatures on pervaporation performance were investigated. The experimental results showed that pervaporation performance of the SA-PVA/PSF composite membranes for ethanol-water solution exhibited a high separation factor although they had a relatively low permeation flux. As SA concentration in SA-PVA coating solution was 66.7% and the operating temperature was 40 ℃, SA-PVA/PSF hollow fiber composite membrane （PS4） had a separation factor of 886 and flux of 12.6 g/（m^2·h）. Besides, SA-PVA/PSF hollow fiber composite membranes （PS3 and PS4） were used for the investigation of the effect of ethanol concentration in the feed solution on pervaporation performance.
基金Supported by the Natural Science Foundation of Tianjin (No.05YFJ MJC04200)
文摘Several kinds of chloromethyl polysulfones （CMPF） with different chlorinity and reactive groups were synthesized by Friedel.crafts reaction, which could be utilized as reactively matrix membrane materials. The CMPF hollow matrix membranes were prepared with phase inversion by utilization of CMPF/additive/DMAC casting solution and CMPF as membrane materials. It was found that the effects of additive content, bore liquid and dry spinning distance on the structure of CMPF hollow fiber matrix membrane were different. A high qualified palysulfone hollow fiber chelating membrane modified with thiourea as chelating groups was prepared using CMPF as membrane matrix materials, through the reaction between thiourea and CMPF hollow fiber matrix membrane to afford the methyl iso-thiourium polysulfone. The experimental results showed that thermal drawing could increase the mechanical properties of matrix membrane, and the thermal treatment could increase the homogeneity and stability of the structure of polysulfoue hollow fiber chelating membrane modified with thiourea.
