Although hydrophilic membranes are desired for reducing resistance to water permeation, hydrophilic surfaces are not used in the water-in-oil(W/O) membrane emulsification process because water spreads on the hydrophil...Although hydrophilic membranes are desired for reducing resistance to water permeation, hydrophilic surfaces are not used in the water-in-oil(W/O) membrane emulsification process because water spreads on the hydrophilic surface without forming droplets. Here, we report that a hydrophilic ceramic membrane can form a hydrophobic interface in diesel at a higher temperature;interestingly, the experiments show that the contact angle increases when the temperature rises. The hydrophilic membrane surface evolves into a hydrophobic interface, particularly near the boiling point of water, resulting in a water contact angle of 147.5° ± 1.2°. This work established a method for preparing W/O monodispersed emulsions by direct emulsification of hydrophilic ceramic membranes at a temperature close to the boiling point of water.Additionally, it made high flux of membrane emulsification of monodispersed W/O emulsions possible,which satisfied the industrial requirements of fluidized catalytic cracking in the petrochemical industry.展开更多
A hybrid system combined with a non-contact membrane and bubbling absorption is proposed to capture CO_(2) from flue gas.The non-contact way of membrane and liquid absorbent effectively avoids the reduction of gas dif...A hybrid system combined with a non-contact membrane and bubbling absorption is proposed to capture CO_(2) from flue gas.The non-contact way of membrane and liquid absorbent effectively avoids the reduction of gas diffusion flux through the membrane.High-porosity ceramic membranes in hybrid systems are used for gas-solid separation in fuel gas treatment.Due to the high content of H_(2)O and cement dust in the flue gas of the cement plant,the membrane is hydrophobically modified by polytetrafluoroethylene(PTFE)to improve its anti-water,anti-fouling,and self-cleaning performances.The results show that the diffusion flux of CO_(2) through the membrane is still higher than 7.0×10^(−3) mol/m^(2)s(20%CO_(2) concentration)even under the influence of water and cement dust.In addition,slaked lime selected as the absorbent is cheap and the product after bubbling absorption is nano-scale light calcium carbonate.To sum up,the hybrid system combining non-contact membrane and bubbling absorption is expected to be used to capture carbon dioxide from the flue gas of the cement plant.展开更多
SAPO-34 zeolite membranes show high efficiency for CO2/CH4 separation but suffer from the reduction of separation performance when exposed to humid atmosphere.In this work,n-dodecyltrimethoxysilane(DTMS)was used to mo...SAPO-34 zeolite membranes show high efficiency for CO2/CH4 separation but suffer from the reduction of separation performance when exposed to humid atmosphere.In this work,n-dodecyltrimethoxysilane(DTMS)was used to modify the hollow fibers supported SAPO-34 membranes to increase the external surface hydrophobicity and thus sustain their performance under moisture environment.The modified membranes were fully characterized.Their separation performance was extensively investigated in both dry and wet gaseous systems and compared with the un-modified ones.The un-modified SAPO-34 membrane exhibited a high separation selectivity of 160 and CO2 permeance of 1.18×10-6 mol·m-2·s-1·Pa-1 for separation of dry CO2/CH4 at 298 K.However,its separation selectivity declined to 0.9 and the CO2 permeance was only about 1.7×10-8 mol·m-2·s-1·Pa-1 for wet CO2/CH4 at same temperature.High temperature(e.g.353 K)could reduce the effect of moisture to improve SAPO-34 separation selectivity,but further increasing temperature(e.g.373 K)led to decrease in CO2/CH4 separation selectivity.A significant decrease of selectivity was observed at higher pressure drop.The modified SAPO-34 membrane showed decreased CO2 permeance but increased separation selectivity for dry CO2/CH4 gas mixture,and super performance for wet CO2/CH4 gas mixture due to the improved hydrophobicity of membrane surface.A separation selectivity of 65 and CO2 permeance of 4.73×10-8 mol·m-2·s-1·Pa-1 for wet CO2/CH4 mixture can be observed at 353 K with a pressure drop of 0.4 MPa.Furthermore,the modified membrane exhibited stable separation performance during the 120-hour test for wet CO2/CH4 mixture at 353 K.The hydrophobic modification paves a way for SAPO-34 membranes in real applications.展开更多
2,4-Dichlorophenol was removed from wasterwater using a new hydrophobic poly（phthalazinone ether sulfone ketone） （PPESK） hollow fiber membrane by vacuum membrane distillation （VMD）.
In the process of membrane absorption,spontaneous wetting of hydrophobic microporous membrane causes membrane modification and increases membrane phase mass transfer resistance,which have attracted wide interest.Howev...In the process of membrane absorption,spontaneous wetting of hydrophobic microporous membrane causes membrane modification and increases membrane phase mass transfer resistance,which have attracted wide interest.However,due to the limitations of previous testing methods,the study of the spontaneous membrane wetting process is limited.Herein,we present a method for monitoring spontaneous membrane wetting by measuring its alternating current(AC)impedance.The impedance tests of the PVDF flat membranes and hollow fiber membranes were conducted in a two-electrode system.The results of equivalent circuit fitting indicate that the impedance value of the unwetted membrane is about 1.02×10^(10)Ω,which is close to the theoretical value of 1.4×10^(10)Ω,and this method can quantify the electrochemical impedance value of membranes with different degrees of spontaneous wetting.In addition,a method of impedance test for real-time monitoring of spontaneous wetting was designed.During the experiment,the timeliness and continuity of this method are confirmed with exact judgment under different conditions.In future work,the impedance data will be used to build model to predict the percentage of membrane wetting degree.展开更多
In this study, poly(vinilydene fluoride-co-hexafluoropropylene)(PVDF-HFP) was used for preparation of hydrophobic membranes using non-solvent induced phase inversion(NIPS) technique. PVDF-HFP copolymer with concentrat...In this study, poly(vinilydene fluoride-co-hexafluoropropylene)(PVDF-HFP) was used for preparation of hydrophobic membranes using non-solvent induced phase inversion(NIPS) technique. PVDF-HFP copolymer with concentrations of 10 wt% and 12 wt% was prepared to investigate the effect of polymer concentration on pore structure,morphology, hydrophobicity and performance of prepared membranes. Besides, the use of two coagulation baths with the effects of parameters such as coagulant time, polymer type and concentration, and the amount of nonsolvent were studied. The performance of prepared membranes was evaluated based on the permeability and selectivity of oxygen and nitrogen from a gas mixture of nitrogen/oxygen under operating conditions of feed flow rate(1–5 L·min-1), inlet pressure to membrane module(0.1–0.5 MPa) and temperatures between 25 and 45 °C. The results showed that the use of two coagulation baths with different compositions of distillated water and isopropanol,coagulant time, polymer type and concentration, and the amount of non-solvent additive have the most effect on pore structure, morphology, thickness, roughness and crystallinity of fabricated membranes. Porosity ranges for the three fabricated membranes were determined, where the maximum porosity was 73.889% and the minimum value was 56.837%. Also, the maximum and minimum average thicknesses of membrane were 320.85 μm and115 μm. Besides, the values of 4.7504 × 10-7 mol· m-2· s-1· Pa-1, 0.525 and 902.126 nm were achieved for maximum oxygen permeance, O2/N2 selectivity and roughness, respectively.展开更多
A novel matrix of macropore cellulose membrane was prepared by chemical graft, and immobilized the cationic charged groups as affinity ligands. The prepared membrane Fan be used for the removal of endotoxin from human...A novel matrix of macropore cellulose membrane was prepared by chemical graft, and immobilized the cationic charged groups as affinity ligands. The prepared membrane Fan be used for the removal of endotoxin from human serum albumin (HSA) solutions. With a cartridge of 20 sheets affinity membrane of 47 mm diameter, the endotoxin level in HSA solution can be reduced ro 0.027 eu/mL. Recovery of HSA was over 95%.展开更多
Microstructure in selective layer has played a decisive role in permselectivity of nanofiltration(NF) membranes,and nanomaterials were well-known additives that had been applied to mediate the microstructure and perme...Microstructure in selective layer has played a decisive role in permselectivity of nanofiltration(NF) membranes,and nanomaterials were well-known additives that had been applied to mediate the microstructure and permeability of polyamide NF membranes. However, nanoadditives generally displayed a poor dispersion in membranes or in fabrication process. To solve this problem, we showed an interesting concept that novel NF membranes with hybrid selective layer consisting of flexible polyisobutylene(PIB) and rigid polyamide could be fabricated from well-defined interfacial polymerization. The hydrophobic polymer mediated phase separation and microdomains formation in polyamide layer were found. The immiscibility between the rigid polyamide and flexible PIB as well as the resultant interface effect was interpreted as the reason for the polymer enhanced permselectivity, which was similar with the well-known thin film nanocomposite(TFN) membranes that nanoparticles incorporated contributed significantly to membrane permeability and rejection performance.Our results have demonstrated that novel NF membranes with enhanced performance can be prepared from immiscible polymers, which is a new area that has not been extensively studied before.展开更多
Carbon monoxide releasing molecules (CORMs) have been recently developed for research and pharmacological purposes. A considerable amount of studies demonstrated a wide spectrum of biological activities for lipophilic...Carbon monoxide releasing molecules (CORMs) have been recently developed for research and pharmacological purposes. A considerable amount of studies demonstrated a wide spectrum of biological activities for lipophilic CORM-2 (tricarbonyldichlororuthenium (II) dimer). It is generally accepted that the liberated gas provides the specific activities to CORMs, with a little attention paid to any possible effect of complementary core molecules. However, the versatile repertoire of actions attributed to CORM-2 is surprisingly wide for CO, a molecule with the sole chemical activity of binding to ferrous iron in protein prosthetic groups. The study was designed to analyze CORM-2 and its core molecule (“i”CORM) activities at a molecular level. With respect to the hydrophobic nature of the compounds, we followed their interactions with several amphipathic entities: the heme sites of hemoproteins, heme binding proteins and cell membranes. CORM-2/“i”CORM decreased the Soret optical density of hemoglobin and myoglobin, indicating that both compounds interact with the protein amphipathic site in the heme pocket. Pre-addition of CORM-2/“i”CORM to the apo-forms of the plasma heme binding proteins, hemopexin and albumin, partially abolished their heme binding capacity. In contrast, the compounds had no effect on the preformed heme-protein complexes. Addition of CORM-2/“i”- CORM to blood or isolated erythrocytes revealed aggregation of the cells or lysis, depending on the rea-gent-to-cells ratio. It was concluded that the ruthenium containing core molecule of CORM-2 may be physiologically active due to non-specific hydrophobic interactions. As each type of CORMs is expected to have a different mode of action beyond CO activity, their potential therapeutic uses will require clarification.展开更多
The wet phase inversion process was used to prepare a kind of medical exhaust membranes with super-hydrophobicity and good gas permeability capacity by using non-woven fabric as the support base.The influences of solu...The wet phase inversion process was used to prepare a kind of medical exhaust membranes with super-hydrophobicity and good gas permeability capacity by using non-woven fabric as the support base.The influences of solution temperature,the evaporation time,the content of the non-solvent additive and the ratio of polyvinyl chloride(PVC)/polyacrylonitrile(PAN) on the gas permeability capacity and hydrostatic pressure of the resultant membranes were investigated.A kind of composite membrane with gas permeability about 2 800 mL/min and hydrostatic pressure of 36 kPa was obtained.In addition,the relationship between the properties and structure of the membrane was analyzed.展开更多
疏水性差热导率高是制约膜蒸馏在高盐度废水处理领域运用的关键技术参数。为提高膜的疏水性的同时降低膜的导热性能,对自制的SiO_(2)/PVDF复合膜进行了分子模拟和污染物为Ni^(2+)、Co^(2+)和Mg^(2+)的耐污染实验。通过Materials Studio ...疏水性差热导率高是制约膜蒸馏在高盐度废水处理领域运用的关键技术参数。为提高膜的疏水性的同时降低膜的导热性能,对自制的SiO_(2)/PVDF复合膜进行了分子模拟和污染物为Ni^(2+)、Co^(2+)和Mg^(2+)的耐污染实验。通过Materials Studio (MS)软件建立了膜的分子模型。结果表明,羟基含量为40%膜的导热系数最低;采用膜蒸馏+MVR(机械蒸汽再压缩蒸发技术)组合工艺可降低30.61%的处理成本。各污染物与膜表面的非键作用力中,氢键作用能(E_(el))为负值且是污染物富集在膜表面的主要作用力。此外,Ni^(2+)离子对膜的渗透性能影响最大。展开更多
基金the support from the National Key Research and Development Program of China (2021YFB3801303)the National Natural Science Foundation of China (21838005, 21921006)the Key Scientific Research and Development Projects of Jiangsu Province (BE201800901)。
文摘Although hydrophilic membranes are desired for reducing resistance to water permeation, hydrophilic surfaces are not used in the water-in-oil(W/O) membrane emulsification process because water spreads on the hydrophilic surface without forming droplets. Here, we report that a hydrophilic ceramic membrane can form a hydrophobic interface in diesel at a higher temperature;interestingly, the experiments show that the contact angle increases when the temperature rises. The hydrophilic membrane surface evolves into a hydrophobic interface, particularly near the boiling point of water, resulting in a water contact angle of 147.5° ± 1.2°. This work established a method for preparing W/O monodispersed emulsions by direct emulsification of hydrophilic ceramic membranes at a temperature close to the boiling point of water.Additionally, it made high flux of membrane emulsification of monodispersed W/O emulsions possible,which satisfied the industrial requirements of fluidized catalytic cracking in the petrochemical industry.
文摘A hybrid system combined with a non-contact membrane and bubbling absorption is proposed to capture CO_(2) from flue gas.The non-contact way of membrane and liquid absorbent effectively avoids the reduction of gas diffusion flux through the membrane.High-porosity ceramic membranes in hybrid systems are used for gas-solid separation in fuel gas treatment.Due to the high content of H_(2)O and cement dust in the flue gas of the cement plant,the membrane is hydrophobically modified by polytetrafluoroethylene(PTFE)to improve its anti-water,anti-fouling,and self-cleaning performances.The results show that the diffusion flux of CO_(2) through the membrane is still higher than 7.0×10^(−3) mol/m^(2)s(20%CO_(2) concentration)even under the influence of water and cement dust.In addition,slaked lime selected as the absorbent is cheap and the product after bubbling absorption is nano-scale light calcium carbonate.To sum up,the hybrid system combining non-contact membrane and bubbling absorption is expected to be used to capture carbon dioxide from the flue gas of the cement plant.
基金Supported by the National Natural Science Foundation of China(21490585,21776128)the“Six Top Talents”and“333 Talent Project”of Jiangsu Province,State Key Laboratory of Materials-Oriented Chemical Engineering(ZK201602,ZK201719)Priority Academy Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘SAPO-34 zeolite membranes show high efficiency for CO2/CH4 separation but suffer from the reduction of separation performance when exposed to humid atmosphere.In this work,n-dodecyltrimethoxysilane(DTMS)was used to modify the hollow fibers supported SAPO-34 membranes to increase the external surface hydrophobicity and thus sustain their performance under moisture environment.The modified membranes were fully characterized.Their separation performance was extensively investigated in both dry and wet gaseous systems and compared with the un-modified ones.The un-modified SAPO-34 membrane exhibited a high separation selectivity of 160 and CO2 permeance of 1.18×10-6 mol·m-2·s-1·Pa-1 for separation of dry CO2/CH4 at 298 K.However,its separation selectivity declined to 0.9 and the CO2 permeance was only about 1.7×10-8 mol·m-2·s-1·Pa-1 for wet CO2/CH4 at same temperature.High temperature(e.g.353 K)could reduce the effect of moisture to improve SAPO-34 separation selectivity,but further increasing temperature(e.g.373 K)led to decrease in CO2/CH4 separation selectivity.A significant decrease of selectivity was observed at higher pressure drop.The modified SAPO-34 membrane showed decreased CO2 permeance but increased separation selectivity for dry CO2/CH4 gas mixture,and super performance for wet CO2/CH4 gas mixture due to the improved hydrophobicity of membrane surface.A separation selectivity of 65 and CO2 permeance of 4.73×10-8 mol·m-2·s-1·Pa-1 for wet CO2/CH4 mixture can be observed at 353 K with a pressure drop of 0.4 MPa.Furthermore,the modified membrane exhibited stable separation performance during the 120-hour test for wet CO2/CH4 mixture at 353 K.The hydrophobic modification paves a way for SAPO-34 membranes in real applications.
文摘2,4-Dichlorophenol was removed from wasterwater using a new hydrophobic poly（phthalazinone ether sulfone ketone） （PPESK） hollow fiber membrane by vacuum membrane distillation （VMD）.
基金Fanatical support from the National Natural Science Foundation of China(21576011)and the kind supply of electrochemical workstation from Prof。
文摘In the process of membrane absorption,spontaneous wetting of hydrophobic microporous membrane causes membrane modification and increases membrane phase mass transfer resistance,which have attracted wide interest.However,due to the limitations of previous testing methods,the study of the spontaneous membrane wetting process is limited.Herein,we present a method for monitoring spontaneous membrane wetting by measuring its alternating current(AC)impedance.The impedance tests of the PVDF flat membranes and hollow fiber membranes were conducted in a two-electrode system.The results of equivalent circuit fitting indicate that the impedance value of the unwetted membrane is about 1.02×10^(10)Ω,which is close to the theoretical value of 1.4×10^(10)Ω,and this method can quantify the electrochemical impedance value of membranes with different degrees of spontaneous wetting.In addition,a method of impedance test for real-time monitoring of spontaneous wetting was designed.During the experiment,the timeliness and continuity of this method are confirmed with exact judgment under different conditions.In future work,the impedance data will be used to build model to predict the percentage of membrane wetting degree.
文摘In this study, poly(vinilydene fluoride-co-hexafluoropropylene)(PVDF-HFP) was used for preparation of hydrophobic membranes using non-solvent induced phase inversion(NIPS) technique. PVDF-HFP copolymer with concentrations of 10 wt% and 12 wt% was prepared to investigate the effect of polymer concentration on pore structure,morphology, hydrophobicity and performance of prepared membranes. Besides, the use of two coagulation baths with the effects of parameters such as coagulant time, polymer type and concentration, and the amount of nonsolvent were studied. The performance of prepared membranes was evaluated based on the permeability and selectivity of oxygen and nitrogen from a gas mixture of nitrogen/oxygen under operating conditions of feed flow rate(1–5 L·min-1), inlet pressure to membrane module(0.1–0.5 MPa) and temperatures between 25 and 45 °C. The results showed that the use of two coagulation baths with different compositions of distillated water and isopropanol,coagulant time, polymer type and concentration, and the amount of non-solvent additive have the most effect on pore structure, morphology, thickness, roughness and crystallinity of fabricated membranes. Porosity ranges for the three fabricated membranes were determined, where the maximum porosity was 73.889% and the minimum value was 56.837%. Also, the maximum and minimum average thicknesses of membrane were 320.85 μm and115 μm. Besides, the values of 4.7504 × 10-7 mol· m-2· s-1· Pa-1, 0.525 and 902.126 nm were achieved for maximum oxygen permeance, O2/N2 selectivity and roughness, respectively.
文摘A novel matrix of macropore cellulose membrane was prepared by chemical graft, and immobilized the cationic charged groups as affinity ligands. The prepared membrane Fan be used for the removal of endotoxin from human serum albumin (HSA) solutions. With a cartridge of 20 sheets affinity membrane of 47 mm diameter, the endotoxin level in HSA solution can be reduced ro 0.027 eu/mL. Recovery of HSA was over 95%.
基金Supported by the National Basic Research Program of China(2015CB655303)the Natural Science Foundation of Zhejiang Province(Q14B040003)
文摘Microstructure in selective layer has played a decisive role in permselectivity of nanofiltration(NF) membranes,and nanomaterials were well-known additives that had been applied to mediate the microstructure and permeability of polyamide NF membranes. However, nanoadditives generally displayed a poor dispersion in membranes or in fabrication process. To solve this problem, we showed an interesting concept that novel NF membranes with hybrid selective layer consisting of flexible polyisobutylene(PIB) and rigid polyamide could be fabricated from well-defined interfacial polymerization. The hydrophobic polymer mediated phase separation and microdomains formation in polyamide layer were found. The immiscibility between the rigid polyamide and flexible PIB as well as the resultant interface effect was interpreted as the reason for the polymer enhanced permselectivity, which was similar with the well-known thin film nanocomposite(TFN) membranes that nanoparticles incorporated contributed significantly to membrane permeability and rejection performance.Our results have demonstrated that novel NF membranes with enhanced performance can be prepared from immiscible polymers, which is a new area that has not been extensively studied before.
文摘Carbon monoxide releasing molecules (CORMs) have been recently developed for research and pharmacological purposes. A considerable amount of studies demonstrated a wide spectrum of biological activities for lipophilic CORM-2 (tricarbonyldichlororuthenium (II) dimer). It is generally accepted that the liberated gas provides the specific activities to CORMs, with a little attention paid to any possible effect of complementary core molecules. However, the versatile repertoire of actions attributed to CORM-2 is surprisingly wide for CO, a molecule with the sole chemical activity of binding to ferrous iron in protein prosthetic groups. The study was designed to analyze CORM-2 and its core molecule (“i”CORM) activities at a molecular level. With respect to the hydrophobic nature of the compounds, we followed their interactions with several amphipathic entities: the heme sites of hemoproteins, heme binding proteins and cell membranes. CORM-2/“i”CORM decreased the Soret optical density of hemoglobin and myoglobin, indicating that both compounds interact with the protein amphipathic site in the heme pocket. Pre-addition of CORM-2/“i”CORM to the apo-forms of the plasma heme binding proteins, hemopexin and albumin, partially abolished their heme binding capacity. In contrast, the compounds had no effect on the preformed heme-protein complexes. Addition of CORM-2/“i”- CORM to blood or isolated erythrocytes revealed aggregation of the cells or lysis, depending on the rea-gent-to-cells ratio. It was concluded that the ruthenium containing core molecule of CORM-2 may be physiologically active due to non-specific hydrophobic interactions. As each type of CORMs is expected to have a different mode of action beyond CO activity, their potential therapeutic uses will require clarification.
文摘The wet phase inversion process was used to prepare a kind of medical exhaust membranes with super-hydrophobicity and good gas permeability capacity by using non-woven fabric as the support base.The influences of solution temperature,the evaporation time,the content of the non-solvent additive and the ratio of polyvinyl chloride(PVC)/polyacrylonitrile(PAN) on the gas permeability capacity and hydrostatic pressure of the resultant membranes were investigated.A kind of composite membrane with gas permeability about 2 800 mL/min and hydrostatic pressure of 36 kPa was obtained.In addition,the relationship between the properties and structure of the membrane was analyzed.
文摘疏水性差热导率高是制约膜蒸馏在高盐度废水处理领域运用的关键技术参数。为提高膜的疏水性的同时降低膜的导热性能,对自制的SiO_(2)/PVDF复合膜进行了分子模拟和污染物为Ni^(2+)、Co^(2+)和Mg^(2+)的耐污染实验。通过Materials Studio (MS)软件建立了膜的分子模型。结果表明,羟基含量为40%膜的导热系数最低;采用膜蒸馏+MVR(机械蒸汽再压缩蒸发技术)组合工艺可降低30.61%的处理成本。各污染物与膜表面的非键作用力中,氢键作用能(E_(el))为负值且是污染物富集在膜表面的主要作用力。此外,Ni^(2+)离子对膜的渗透性能影响最大。
