Pervaporation performance of NaY zeolite membranes is improved by ion-exchange with di-valent nitrate salt.Different nitrate salts,including Co(NO_(3))_(2),Mg(NO_(3))_(2),Zn(NO_(3))_(2),Ca(NO_(3))_(2),Cu(NO_(3))_(2),K...Pervaporation performance of NaY zeolite membranes is improved by ion-exchange with di-valent nitrate salt.Different nitrate salts,including Co(NO_(3))_(2),Mg(NO_(3))_(2),Zn(NO_(3))_(2),Ca(NO_(3))_(2),Cu(NO_(3))_(2),KNO_(3),and AgNO_(3),have great effects on the channel structure and water affinity of the NaY zeolite membrane.When the concentration of nitrate salt,ion-exchange temperature and time are 0.1 mol·L^(-1),50℃and 2 h,the ion-exchange degree order of NaY zeolites is Ag^(+)>K^(+)>Ca^(2+)>Zn^(2+)>>Co^(2+)>Mg^(2+).Especially,Ag^(+)and K^(+)cation exchange degree of NaY zeolites are achieved to 96.54% and 82.77% in this work.BET surface,total pore capacity,pore size distribution and water contact angle of the ion-exchanged NaY zeolites are all disordered by mono-and di-valent cations.Di-valent nitrate salt is favor for increasing the dehydration performance of NaY zeolite membranes by ion-exchange.When the ion-exchange solution is Zn(NO_(3))_(2),the total flux variation and separation factor variation of the NaY membrane(M-5)are -45% and 230% for separation of 10%(mass)H_(2)O/EtOH mixture by pervaporation,and the ion-exchanged membranes showed good reproducibility.展开更多
Heterogeneous catalysts with ultrafine or nano particle size have currently attracted considerable attentions in the chemical and petrochemical production processes, but their large-scale applications remain challengi...Heterogeneous catalysts with ultrafine or nano particle size have currently attracted considerable attentions in the chemical and petrochemical production processes, but their large-scale applications remain challenging because of difficulties associated with their efficient separation from the reaction slurry. A porous ceramic membrane reactor has emerged as a promising method to solve the problem concerning catalysts separation in situ from the reaction mixture and make the production process continuous in heterogeneous catalysis. This article presents a review of the present progress on porous ceramic membrane reactors for heterogeneous catalysis, which covers classification of configurations of porous ceramic membrane reactor, major considerations and some important industrial applications. A special emphasis is paid to major considerations in term of application-oriented ceramic membrane design, optimization of ceramic membrane reactor performance and membrane fouling mechanism. Finally, brief concluding remarks on porous ceramic membrane reactors are given and possible future research interests are also outlined.展开更多
Both activity and stability of the catalyst can be improved in heterogeneous Fenton reaction,in particular,with no limitation for the working p H and no production of the sludge.In this work,a combination of catalyst ...Both activity and stability of the catalyst can be improved in heterogeneous Fenton reaction,in particular,with no limitation for the working p H and no production of the sludge.In this work,a combination of catalyst Cu_2O and pore-channel-dispersed H_2O_2is proposed to treat the pulp wastewater.Degradation degree of CODs in the wastewater was up to 77%in the ceramic membrane reactor using Cu_2O powder(2.0 g·L^(-1))and membranefeeding H_2O_2(0.8 ml·L^(-1))within 60 min.Evolution of·OH radical formation in the advanced oxidation process was analyzed with a fluorescent method.Utilization efficiency of H_2O_2was successfully enhanced by 10%with the membrane distributor.Further on,the catalyst recyclability was evaluated in a five-cycle test.The concentration of copper ions being dissolved in the treated water was monitored with ICP.After Cu_2O/H_2O_2(membrane)treatment the effluent is qualified to discharge with COD concentration lower than 15 mg·L^(-1)with regard to the national standard GB25467-2010.展开更多
1 INTRODUCTIONRapid and precise methods to obtain the diffusion coefficients of counter-ions are im-portant for the characterization of ion exchange membranes.Many theoreticaldescriptions of ion transport in ion excha...1 INTRODUCTIONRapid and precise methods to obtain the diffusion coefficients of counter-ions are im-portant for the characterization of ion exchange membranes.Many theoreticaldescriptions of ion transport in ion exchange membranes have been developed by usingthe principles of irreversible thermodynamics,or the Nernst-Planck equations.Fick’s law can also be used for the description of the transport of ions with equaldiffusivity.However,for counter-ions of different diffusivities,Nerst-Planck展开更多
Catalytic membrane reactors(CMRs),which synergistically carry out separations and reactions,are expected to become a green and sustainable technology in chemical engineering.The use of ceramic membranes in CMRs is bei...Catalytic membrane reactors(CMRs),which synergistically carry out separations and reactions,are expected to become a green and sustainable technology in chemical engineering.The use of ceramic membranes in CMRs is being widely considered because it permits reactions and separations to be carried out under harsh conditions in terms of both temperature and the chemical environment.This article presents the two most important types of CMRs:those based on dense mixed-conducting membranes for gas separation,and those based on porous ceramic membranes for heterogeneous catalytic processes.New developments in and innovative uses of both types of CMRs over the last decade are presented,along with an overview of our recent work in this field.Membrane reactor design,fabrication,and applications related to energy and environmental areas are highlighted.First,the configuration of membranes and membrane reactors are introduced for each of type of membrane reactor.Next,taking typical catalytic reactions as model systems,the design and optimization of CMRs are illustrated.Finally,challenges and difficulties in the process of industrializing the two types of CMRs are addressed,and a view of the future is outlined.展开更多
1 INTRODUCTIONKnowledge of the basic transport phenomena of ions in an ion exchange membrane isimportant for the application of such a membrane.Various studies on the developmentof mathematical models for predicting a...1 INTRODUCTIONKnowledge of the basic transport phenomena of ions in an ion exchange membrane isimportant for the application of such a membrane.Various studies on the developmentof mathematical models for predicting and correlating membrane transport rate havebeen published in recent years.More exact estimation of the diffusion coefficientshas been the subject of chief concern in many of these papers.For a bi-ionic systemwith the same valence,Sato et al.gave a method for estimating diffusion coefficients展开更多
In this paper, the effect of water vapor removal on methanol synthesis capacity from syngas in a fixed-bed membrane reactor is studied considering long-term catalyst deactivation. A dynamic heterogeneous one-dimension...In this paper, the effect of water vapor removal on methanol synthesis capacity from syngas in a fixed-bed membrane reactor is studied considering long-term catalyst deactivation. A dynamic heterogeneous one-dimensional mathematical model that is composed of two sides is developed to predict the performance of this configuration. In this configuration, conventional methanol reactor is supported by an aluminasilica composite membrane layer for water vapor removal from reaction zone. To verify the accuracy of the considered model and assumptions, simulation results of the conventional methanol reactor is compared with the industrial plant data under the same process condition. The membrane reactor improves catalyst life time and enhances CO2 conversion to methanol by overcoming the limitation imposed by thermodynamic equilibrium. This configuration has enhanced the methanol production capacity about 4.06% compared with the industrial methanol reactor during the production time.展开更多
Ion-exchange membranes(IEMs)are utilized in numerous established,emergent,and emerging applications for water,energy,and the environment.This article reviews the five different types of IEM selectivity,namely charge,v...Ion-exchange membranes(IEMs)are utilized in numerous established,emergent,and emerging applications for water,energy,and the environment.This article reviews the five different types of IEM selectivity,namely charge,valence,specific ion,ion/solvent,and ion/uncharged solute selectivities.Technological pathways to advance the selectivities through the sorption and migration mechanisms of transport in IEM are critically analyzed.Because of the underlying principles governing transport,efforts to enhance selectivity by tuning the membrane structural and chemical properties are almost always accompanied by a concomitant decline in permeability of the desired ion.Suppressing the undesired crossover of solvent and neutral species is crucial to realize the practical implementation of several technologies,including bioelectrochemical systems,hypersaline electrodialysis desalination,fuel cells,and redox flow batteries,but the ion/solvent and ion/uncharged solute selectivities are relatively understudied,compared to the ion/ion selectivities.Deepening fundamental understanding of the transport phenomena,specifically the factors underpinning structure-property-performance relationships,will be vital to guide the informed development of more selective IEMs.Innovations in material and membrane design offer opportunities to utilize ion discrimination mechanisms that are radically different from conventional IEMs and potentially depart from the putative permeability-selectivity tradeoff.Advancements in IEM selectivity can contribute to meeting the aqueous separation needs of water,energy,and environmental challenges.展开更多
An insoluble SA-Fe membrane was prepared by being linked soluble sodium alginate with FeCl3. SEM was used to observe its surface structure. 1R spectrum indicated that Fe^3＋ was linked with -COOH and -OH in SA membran...An insoluble SA-Fe membrane was prepared by being linked soluble sodium alginate with FeCl3. SEM was used to observe its surface structure. 1R spectrum indicated that Fe^3＋ was linked with -COOH and -OH in SA membrane. As a cationic exchanging membrane in electrodialysis the membrane was applied in treating inorganic wastewater with high concentration of inorganic ammonia and azote. The results of experiment showed that it was well-selective to ammonia and azote. The percentage of the removal of ammonia and azote in wastewater was up to 80%.展开更多
Graphene-based materials exhibit unique properties that have been sought to utilize for various potential applications. Many studies suggest that graphene-based materials can be cytotoxic, which may be attributed to d...Graphene-based materials exhibit unique properties that have been sought to utilize for various potential applications. Many studies suggest that graphene-based materials can be cytotoxic, which may be attributed to destructive effects on cell membranes.However, there still are conflicting results regarding interactions between graphene-based materials and lipid membranes. Here,through cryo-electron microscopy(Cryo-EM) and dye-leakage experiments along with in silico methods, we found that graphene oxide nanosheets induce significant membrane damage, while the effect of pristine graphene is negligible. We revealed the importance of heterogeneous oxidization of graphene-based nanosheets in damaging vesicle membranes. Moreover, that not only the oxidization degree but also the oxidization loci and membrane tension play important roles in the cytotoxicity of the graphene-based nanosheets.展开更多
The current density is rather low in solid bipolar membranes, because the water transfer rate is relatively slow across solid bipolar membranes made of solid ion-exchange materials. This paper describes the use of po...The current density is rather low in solid bipolar membranes, because the water transfer rate is relatively slow across solid bipolar membranes made of solid ion-exchange materials. This paper describes the use of polymer solutions, such as phosphatic poly(vinyl alcohol) solution, poly(acrylic acid) solution and poly(vinyl alcohol) solutions with dispersed cation/anion-exchange resin particles to prepare bipolar membranes. The 0.1 mol/L NaOH and the 0.05 mol/L H 2SO 4 were used to test the performance of the bipolar membranes. For a fixed liquid layer thickness, both the current density and the selectivity increase with the concentration increase of a polyelectrolyte solution. The maximum current density measured in the experiment was 1497 A/m 2 with a selectivity of 96.8%.展开更多
Heterogeneity is a major obstacle to the success of CAR-T therapy in treating solid tumors. The complex tumor micro-environment and varying phenotypes of tumor cells might result in antigen escape, drug resistance, an...Heterogeneity is a major obstacle to the success of CAR-T therapy in treating solid tumors. The complex tumor micro-environment and varying phenotypes of tumor cells might result in antigen escape, drug resistance, and tumor recurrence. To address this issue, we proposed to use lipid-modified fluorescein isothiocyanate(Lip-FITC) as an artificial ligand to normalize the phenotypes of solid tumor cells. In murine cutaneous melanoma and colon adenocarcinoma that prefer to utilize exogenous long-chain fatty acids, we observed much more uptake of Lip-FITC and significantly increased FITC fluorescence on tumor cell membranes than normal cells. This specific exogenous labeling with FITC enhanced the recognition and selectivity of CART cells in solid tumors, bypassing the limitations derived from antigen expression differences in adoptive cell therapies. Lipid metabolism analysis and in vitro experiments demonstrated the sufficient uptake of long-chain fatty acid(LCFAs)-modified Lip-FITC by solid tumor cells, as well as satisfactory ligand assembly on cell membranes. In solid tumor model, the treatment induced the recognition and initiation of CART cells and successfully suppressed tumor progression through T-cell immunity.展开更多
基金supported by the National Natural Science Foundation of China(21868012 and 21868013)Jiangxi Provincial Department of Science and Technology(20171BCB24005 and 20181ACH80003)。
文摘Pervaporation performance of NaY zeolite membranes is improved by ion-exchange with di-valent nitrate salt.Different nitrate salts,including Co(NO_(3))_(2),Mg(NO_(3))_(2),Zn(NO_(3))_(2),Ca(NO_(3))_(2),Cu(NO_(3))_(2),KNO_(3),and AgNO_(3),have great effects on the channel structure and water affinity of the NaY zeolite membrane.When the concentration of nitrate salt,ion-exchange temperature and time are 0.1 mol·L^(-1),50℃and 2 h,the ion-exchange degree order of NaY zeolites is Ag^(+)>K^(+)>Ca^(2+)>Zn^(2+)>>Co^(2+)>Mg^(2+).Especially,Ag^(+)and K^(+)cation exchange degree of NaY zeolites are achieved to 96.54% and 82.77% in this work.BET surface,total pore capacity,pore size distribution and water contact angle of the ion-exchanged NaY zeolites are all disordered by mono-and di-valent cations.Di-valent nitrate salt is favor for increasing the dehydration performance of NaY zeolite membranes by ion-exchange.When the ion-exchange solution is Zn(NO_(3))_(2),the total flux variation and separation factor variation of the NaY membrane(M-5)are -45% and 230% for separation of 10%(mass)H_(2)O/EtOH mixture by pervaporation,and the ion-exchanged membranes showed good reproducibility.
基金Supported by the National Natural Science Foundation of China （20990222, 21106061）, the National Basic Research Program of China （2009CB623406）, the National Key Science and Technology Program of China （2011BAE07B05） and the Natural Science Foundation of Jiangsu Province, China （BK2010549, BK2009021）.
文摘Heterogeneous catalysts with ultrafine or nano particle size have currently attracted considerable attentions in the chemical and petrochemical production processes, but their large-scale applications remain challenging because of difficulties associated with their efficient separation from the reaction slurry. A porous ceramic membrane reactor has emerged as a promising method to solve the problem concerning catalysts separation in situ from the reaction mixture and make the production process continuous in heterogeneous catalysis. This article presents a review of the present progress on porous ceramic membrane reactors for heterogeneous catalysis, which covers classification of configurations of porous ceramic membrane reactor, major considerations and some important industrial applications. A special emphasis is paid to major considerations in term of application-oriented ceramic membrane design, optimization of ceramic membrane reactor performance and membrane fouling mechanism. Finally, brief concluding remarks on porous ceramic membrane reactors are given and possible future research interests are also outlined.
基金Supported by the Prospective Research Project of Jiangsu Province(BY2014005-06)
文摘Both activity and stability of the catalyst can be improved in heterogeneous Fenton reaction,in particular,with no limitation for the working p H and no production of the sludge.In this work,a combination of catalyst Cu_2O and pore-channel-dispersed H_2O_2is proposed to treat the pulp wastewater.Degradation degree of CODs in the wastewater was up to 77%in the ceramic membrane reactor using Cu_2O powder(2.0 g·L^(-1))and membranefeeding H_2O_2(0.8 ml·L^(-1))within 60 min.Evolution of·OH radical formation in the advanced oxidation process was analyzed with a fluorescent method.Utilization efficiency of H_2O_2was successfully enhanced by 10%with the membrane distributor.Further on,the catalyst recyclability was evaluated in a five-cycle test.The concentration of copper ions being dissolved in the treated water was monitored with ICP.After Cu_2O/H_2O_2(membrane)treatment the effluent is qualified to discharge with COD concentration lower than 15 mg·L^(-1)with regard to the national standard GB25467-2010.
基金Supported by a grant from Chinese Pastdoctoral Foundation
文摘1 INTRODUCTIONRapid and precise methods to obtain the diffusion coefficients of counter-ions are im-portant for the characterization of ion exchange membranes.Many theoreticaldescriptions of ion transport in ion exchange membranes have been developed by usingthe principles of irreversible thermodynamics,or the Nernst-Planck equations.Fick’s law can also be used for the description of the transport of ions with equaldiffusivity.However,for counter-ions of different diffusivities,Nerst-Planck
基金the National Natural Science Foundation of China(20990222,21006047,21706117,and 21706118)the Natural Science Foundation of Jiangsu(BK20170978 and BK20170970)+1 种基金the State Key Laboratory of Material-Oriented Chemical Engineering(ZK201609)the Innovative Research Team Program by the Ministry of Education of China(IRT17R54).
文摘Catalytic membrane reactors(CMRs),which synergistically carry out separations and reactions,are expected to become a green and sustainable technology in chemical engineering.The use of ceramic membranes in CMRs is being widely considered because it permits reactions and separations to be carried out under harsh conditions in terms of both temperature and the chemical environment.This article presents the two most important types of CMRs:those based on dense mixed-conducting membranes for gas separation,and those based on porous ceramic membranes for heterogeneous catalytic processes.New developments in and innovative uses of both types of CMRs over the last decade are presented,along with an overview of our recent work in this field.Membrane reactor design,fabrication,and applications related to energy and environmental areas are highlighted.First,the configuration of membranes and membrane reactors are introduced for each of type of membrane reactor.Next,taking typical catalytic reactions as model systems,the design and optimization of CMRs are illustrated.Finally,challenges and difficulties in the process of industrializing the two types of CMRs are addressed,and a view of the future is outlined.
基金Supported by the Post-doctoral Foundation of China
文摘1 INTRODUCTIONKnowledge of the basic transport phenomena of ions in an ion exchange membrane isimportant for the application of such a membrane.Various studies on the developmentof mathematical models for predicting and correlating membrane transport rate havebeen published in recent years.More exact estimation of the diffusion coefficientshas been the subject of chief concern in many of these papers.For a bi-ionic systemwith the same valence,Sato et al.gave a method for estimating diffusion coefficients
文摘In this paper, the effect of water vapor removal on methanol synthesis capacity from syngas in a fixed-bed membrane reactor is studied considering long-term catalyst deactivation. A dynamic heterogeneous one-dimensional mathematical model that is composed of two sides is developed to predict the performance of this configuration. In this configuration, conventional methanol reactor is supported by an aluminasilica composite membrane layer for water vapor removal from reaction zone. To verify the accuracy of the considered model and assumptions, simulation results of the conventional methanol reactor is compared with the industrial plant data under the same process condition. The membrane reactor improves catalyst life time and enhances CO2 conversion to methanol by overcoming the limitation imposed by thermodynamic equilibrium. This configuration has enhanced the methanol production capacity about 4.06% compared with the industrial methanol reactor during the production time.
文摘Ion-exchange membranes(IEMs)are utilized in numerous established,emergent,and emerging applications for water,energy,and the environment.This article reviews the five different types of IEM selectivity,namely charge,valence,specific ion,ion/solvent,and ion/uncharged solute selectivities.Technological pathways to advance the selectivities through the sorption and migration mechanisms of transport in IEM are critically analyzed.Because of the underlying principles governing transport,efforts to enhance selectivity by tuning the membrane structural and chemical properties are almost always accompanied by a concomitant decline in permeability of the desired ion.Suppressing the undesired crossover of solvent and neutral species is crucial to realize the practical implementation of several technologies,including bioelectrochemical systems,hypersaline electrodialysis desalination,fuel cells,and redox flow batteries,but the ion/solvent and ion/uncharged solute selectivities are relatively understudied,compared to the ion/ion selectivities.Deepening fundamental understanding of the transport phenomena,specifically the factors underpinning structure-property-performance relationships,will be vital to guide the informed development of more selective IEMs.Innovations in material and membrane design offer opportunities to utilize ion discrimination mechanisms that are radically different from conventional IEMs and potentially depart from the putative permeability-selectivity tradeoff.Advancements in IEM selectivity can contribute to meeting the aqueous separation needs of water,energy,and environmental challenges.
基金Development and Evolution Program of Fujian. No.04FSD.
文摘An insoluble SA-Fe membrane was prepared by being linked soluble sodium alginate with FeCl3. SEM was used to observe its surface structure. 1R spectrum indicated that Fe^3＋ was linked with -COOH and -OH in SA membrane. As a cationic exchanging membrane in electrodialysis the membrane was applied in treating inorganic wastewater with high concentration of inorganic ammonia and azote. The results of experiment showed that it was well-selective to ammonia and azote. The percentage of the removal of ammonia and azote in wastewater was up to 80%.
基金supported by the National Basic Research Program of China(Grant No.2015CB856304)the National Natural Science Foundation of China(Grant Nos.11772054,11772055,11532009,and 11402145)+1 种基金Natural Science Foundation of Shanghai(Grant No.18ZR1418800)National Institutes of Health(Grant No.R35GM128837)
文摘Graphene-based materials exhibit unique properties that have been sought to utilize for various potential applications. Many studies suggest that graphene-based materials can be cytotoxic, which may be attributed to destructive effects on cell membranes.However, there still are conflicting results regarding interactions between graphene-based materials and lipid membranes. Here,through cryo-electron microscopy(Cryo-EM) and dye-leakage experiments along with in silico methods, we found that graphene oxide nanosheets induce significant membrane damage, while the effect of pristine graphene is negligible. We revealed the importance of heterogeneous oxidization of graphene-based nanosheets in damaging vesicle membranes. Moreover, that not only the oxidization degree but also the oxidization loci and membrane tension play important roles in the cytotoxicity of the graphene-based nanosheets.
文摘The current density is rather low in solid bipolar membranes, because the water transfer rate is relatively slow across solid bipolar membranes made of solid ion-exchange materials. This paper describes the use of polymer solutions, such as phosphatic poly(vinyl alcohol) solution, poly(acrylic acid) solution and poly(vinyl alcohol) solutions with dispersed cation/anion-exchange resin particles to prepare bipolar membranes. The 0.1 mol/L NaOH and the 0.05 mol/L H 2SO 4 were used to test the performance of the bipolar membranes. For a fixed liquid layer thickness, both the current density and the selectivity increase with the concentration increase of a polyelectrolyte solution. The maximum current density measured in the experiment was 1497 A/m 2 with a selectivity of 96.8%.
基金supported by the National Natural Science Foundation of China (52103319, 22135005, 51988102)。
文摘Heterogeneity is a major obstacle to the success of CAR-T therapy in treating solid tumors. The complex tumor micro-environment and varying phenotypes of tumor cells might result in antigen escape, drug resistance, and tumor recurrence. To address this issue, we proposed to use lipid-modified fluorescein isothiocyanate(Lip-FITC) as an artificial ligand to normalize the phenotypes of solid tumor cells. In murine cutaneous melanoma and colon adenocarcinoma that prefer to utilize exogenous long-chain fatty acids, we observed much more uptake of Lip-FITC and significantly increased FITC fluorescence on tumor cell membranes than normal cells. This specific exogenous labeling with FITC enhanced the recognition and selectivity of CART cells in solid tumors, bypassing the limitations derived from antigen expression differences in adoptive cell therapies. Lipid metabolism analysis and in vitro experiments demonstrated the sufficient uptake of long-chain fatty acid(LCFAs)-modified Lip-FITC by solid tumor cells, as well as satisfactory ligand assembly on cell membranes. In solid tumor model, the treatment induced the recognition and initiation of CART cells and successfully suppressed tumor progression through T-cell immunity.
