A novel technology of preparation of felt-metal supported modified polyvinyl alcohol(PVA) ultrafiltration(UF) membrane was invented, which could avoid the blockage of the holes of support layer and the leakage of ...A novel technology of preparation of felt-metal supported modified polyvinyl alcohol(PVA) ultrafiltration(UF) membrane was invented, which could avoid the blockage of the holes of support layer and the leakage of the casting solution through the holes of support layer. Felt-metal supported ferric sulfate modified PVA composite UF membranes were prepared by the innovative technology. The results show that the composite membranes are used to treat 1 000 mg/L oil/water emulsion at trans-membrane pressure from 0.25 to 0.45 MPa, the permeate flux is from 36 to 52 L/(m2·h), and the retention of chemical oxygen demand(COD) is over 92%. The composite membrane resistance increases with the increase of trans-naembrane pressure.展开更多
concentrating sulfuric acid by membrane distillation in a flat sheet direct contact membrane distillation device with a self made metal PTFE composite membrane has been studied. The effect of sulfuric acid concentrati...concentrating sulfuric acid by membrane distillation in a flat sheet direct contact membrane distillation device with a self made metal PTFE composite membrane has been studied. The effect of sulfuric acid concentration of feed, the flowrate and liquor temperature in high temperature side and low temperature side on the flux and separation efficiency is investigated. The stability of this composite membrane is also inspected. The experimental results show that the metal PTFE composite membrane can be used in membrane distillation, and its properties are very stable. It is feasible to concentrate sulfuric acid by membrane distillation with this membrane.展开更多
Metal-polyvinyl alcohol(PVA) composite ultrafiltration membranes were prepared by coating a certain concentration of PVA solution on metallic fiber sintered membranes. The effects of preparation conditions, such as th...Metal-polyvinyl alcohol(PVA) composite ultrafiltration membranes were prepared by coating a certain concentration of PVA solution on metallic fiber sintered membranes. The effects of preparation conditions, such as the coating solution concentration, sequence and times of coating, and heat-treatment on the properties of the composite membranes were studied. The results show that the hole diameter of the composite membrane decreases with the increase of the concentration of PVA, the hole diameter of composite membrane is different when the sequence of coating is different. When the higher concentration of PVA solution is used to coat the metallic membrane for the first time and the other smaller one for the second time, the hole diameter of the composite membrane is relatively small, compared with that of the composite membrane made by the smaller concentration of PVA solution for the first time and the other higher one for the second time. The holes of the composite membrane contract and the stability of the membrane is improved by heat treatment. When metal-PVA composite hydrophilic membranes are used to treat the oil/water emulsion with the concentration of 1 000 mg·L -1 , the retention is from 80% to 90%, and the permeate flux is from 15 L·m -2 ·h -1 to 40 L·m -2 ·h -1 at pressure of 0.2 to 0.3 MPa.展开更多
Al2O3 ceramic powder was applied to modify the large pores defects on the surface of the porous metal Ti support,in situ oxidation method was a convenient method to prepare defect free ceramic/Ti composite membranes o...Al2O3 ceramic powder was applied to modify the large pores defects on the surface of the porous metal Ti support,in situ oxidation method was a convenient method to prepare defect free ceramic/Ti composite membranes on this basis.In situ oxidation conditions experimental results show that the best condition for preparing the TiO2-Al2O3/Ti composite membrane is under 800°C for 2 h,and the microstructure and pore sizes of the TiO2-Al2O3/Ti composite membranes are affected obviously.The thickness and composition of the TiO2/Ti composite membranes are determined by SEM and XRD completely.The pore size distribution of the composite membrane is measured by bubble pressure method,the most probable aperture is about 3.12μm,while the average pore size of defect free TiO2-Al2O3/Ti is about 3.23μm.After ultrasonic treatment,the slight weight change of membranes reveals no observable change,which indicates that TiO2-Al2O3/Ti composite membranes maintain a good stability.展开更多
MoS2/γ-Al2O3 ceramic composite membrane is successfully synthesized by the sol-gel method based on the inorganic salt route. The aluminum hydrate sol derived from the inorganic salt Al(NO3)3, whose transparence and ...MoS2/γ-Al2O3 ceramic composite membrane is successfully synthesized by the sol-gel method based on the inorganic salt route. The aluminum hydrate sol derived from the inorganic salt Al(NO3)3, whose transparence and viscosity are 97% and 1.2 × 10-3 Pa. s, respectively, can be formed through adjusting the ratio of the peptizing agent H+ to Al3+ to 0.3. The aluminum hydrate gel at 110℃ is amorphous in structure and is heat-treated in air at 800℃ to form γ-Al2O3. The precursor derived from the mixture solution of ammonium molybdate, thioacetamide and a reducing agent, can be transformed into crystal MoS2 under reducing condition at 800℃. MoS2/γ-Al2O3 composite membrane is an organic whole and bps no gradation from MoS2 layer to γ-Al2O3 Iayer. The separation factor a H2/H2S through the MoS2/γ-Al2O3 composite membrane increase with rising temperature and a H2/H2S at 600℃ is 4.45 higher than the theoretical separation factor produced by the ideal Knudsen diffusion.展开更多
In order to further improve the driving performance of ionic polymer metal composites(IPMCs),Nafion/graphene quantum dots(GQDs)hybrid membranes incorporating GQDs with various contents of 0,0.1 wt.%,0.5 wt.%,1.0 wt.%,...In order to further improve the driving performance of ionic polymer metal composites(IPMCs),Nafion/graphene quantum dots(GQDs)hybrid membranes incorporating GQDs with various contents of 0,0.1 wt.%,0.5 wt.%,1.0 wt.%,2.0 wt.%and 4.0 wt.%were fabricated by solution casting,and then IPMCs were manufactured by electroless plating.The water contents and elastic moduli of the hybrid membranes were tested.The morphology characteristics of the hybrid membranes and the IPMCs were observed,and the current,AC impedance,blocking force and displacement of the IPMCs were measured.The results show that the elastic modulus of the hybrid membranes decreases,the water content increases,and the actuation performance of the IPMCs improves significantly after the addition of GQDs.IPMC with 1.0 wt.%GQDs exhibits the best driving property.Compared with the IPMC without GQDs,the working current,ion conductivity,blocking force,and tip displacement increase by 94.67%,311.11%,53.66%,and 66.07%,respectively.These results lay a solid foundation for the preparation of IPMCs with high performance,and further broaden their applications in biomedical devices and bionic robots.展开更多
文摘A novel technology of preparation of felt-metal supported modified polyvinyl alcohol(PVA) ultrafiltration(UF) membrane was invented, which could avoid the blockage of the holes of support layer and the leakage of the casting solution through the holes of support layer. Felt-metal supported ferric sulfate modified PVA composite UF membranes were prepared by the innovative technology. The results show that the composite membranes are used to treat 1 000 mg/L oil/water emulsion at trans-membrane pressure from 0.25 to 0.45 MPa, the permeate flux is from 36 to 52 L/(m2·h), and the retention of chemical oxygen demand(COD) is over 92%. The composite membrane resistance increases with the increase of trans-naembrane pressure.
文摘concentrating sulfuric acid by membrane distillation in a flat sheet direct contact membrane distillation device with a self made metal PTFE composite membrane has been studied. The effect of sulfuric acid concentration of feed, the flowrate and liquor temperature in high temperature side and low temperature side on the flux and separation efficiency is investigated. The stability of this composite membrane is also inspected. The experimental results show that the metal PTFE composite membrane can be used in membrane distillation, and its properties are very stable. It is feasible to concentrate sulfuric acid by membrane distillation with this membrane.
文摘Metal-polyvinyl alcohol(PVA) composite ultrafiltration membranes were prepared by coating a certain concentration of PVA solution on metallic fiber sintered membranes. The effects of preparation conditions, such as the coating solution concentration, sequence and times of coating, and heat-treatment on the properties of the composite membranes were studied. The results show that the hole diameter of the composite membrane decreases with the increase of the concentration of PVA, the hole diameter of composite membrane is different when the sequence of coating is different. When the higher concentration of PVA solution is used to coat the metallic membrane for the first time and the other smaller one for the second time, the hole diameter of the composite membrane is relatively small, compared with that of the composite membrane made by the smaller concentration of PVA solution for the first time and the other higher one for the second time. The holes of the composite membrane contract and the stability of the membrane is improved by heat treatment. When metal-PVA composite hydrophilic membranes are used to treat the oil/water emulsion with the concentration of 1 000 mg·L -1 , the retention is from 80% to 90%, and the permeate flux is from 15 L·m -2 ·h -1 to 40 L·m -2 ·h -1 at pressure of 0.2 to 0.3 MPa.
基金Projects(212006065,21666018)supported by the National Natural Science Foundation of China
文摘Al2O3 ceramic powder was applied to modify the large pores defects on the surface of the porous metal Ti support,in situ oxidation method was a convenient method to prepare defect free ceramic/Ti composite membranes on this basis.In situ oxidation conditions experimental results show that the best condition for preparing the TiO2-Al2O3/Ti composite membrane is under 800°C for 2 h,and the microstructure and pore sizes of the TiO2-Al2O3/Ti composite membranes are affected obviously.The thickness and composition of the TiO2/Ti composite membranes are determined by SEM and XRD completely.The pore size distribution of the composite membrane is measured by bubble pressure method,the most probable aperture is about 3.12μm,while the average pore size of defect free TiO2-Al2O3/Ti is about 3.23μm.After ultrasonic treatment,the slight weight change of membranes reveals no observable change,which indicates that TiO2-Al2O3/Ti composite membranes maintain a good stability.
文摘MoS2/γ-Al2O3 ceramic composite membrane is successfully synthesized by the sol-gel method based on the inorganic salt route. The aluminum hydrate sol derived from the inorganic salt Al(NO3)3, whose transparence and viscosity are 97% and 1.2 × 10-3 Pa. s, respectively, can be formed through adjusting the ratio of the peptizing agent H+ to Al3+ to 0.3. The aluminum hydrate gel at 110℃ is amorphous in structure and is heat-treated in air at 800℃ to form γ-Al2O3. The precursor derived from the mixture solution of ammonium molybdate, thioacetamide and a reducing agent, can be transformed into crystal MoS2 under reducing condition at 800℃. MoS2/γ-Al2O3 composite membrane is an organic whole and bps no gradation from MoS2 layer to γ-Al2O3 Iayer. The separation factor a H2/H2S through the MoS2/γ-Al2O3 composite membrane increase with rising temperature and a H2/H2S at 600℃ is 4.45 higher than the theoretical separation factor produced by the ideal Knudsen diffusion.
基金Projects(51605220,U1637101)supported by the National Natural Science Foundation of ChinaProject(BK20160793)supported by the Jiangsu Provincial Natural Science Foundation,ChinaProject(NS2020029)supported by the Fundamental Research Funds for the Central Universities,China。
文摘In order to further improve the driving performance of ionic polymer metal composites(IPMCs),Nafion/graphene quantum dots(GQDs)hybrid membranes incorporating GQDs with various contents of 0,0.1 wt.%,0.5 wt.%,1.0 wt.%,2.0 wt.%and 4.0 wt.%were fabricated by solution casting,and then IPMCs were manufactured by electroless plating.The water contents and elastic moduli of the hybrid membranes were tested.The morphology characteristics of the hybrid membranes and the IPMCs were observed,and the current,AC impedance,blocking force and displacement of the IPMCs were measured.The results show that the elastic modulus of the hybrid membranes decreases,the water content increases,and the actuation performance of the IPMCs improves significantly after the addition of GQDs.IPMC with 1.0 wt.%GQDs exhibits the best driving property.Compared with the IPMC without GQDs,the working current,ion conductivity,blocking force,and tip displacement increase by 94.67%,311.11%,53.66%,and 66.07%,respectively.These results lay a solid foundation for the preparation of IPMCs with high performance,and further broaden their applications in biomedical devices and bionic robots.