A multi-layer mesoporous silicalite-1 membrane supported on commercially available porous alumina tubes was prepared by firstly dip-coating the tubes in silica colloid sol and then using a hydrothermal synthetic proce...A multi-layer mesoporous silicalite-1 membrane supported on commercially available porous alumina tubes was prepared by firstly dip-coating the tubes in silica colloid sol and then using a hydrothermal synthetic process.The mesoporous silicalite-1 membrane was further modified by grafting organosilane compounds with various alkyl chains length(C_nH_(2n+1)(CH_3)_2SiCl;n = 1,3,8,12 and 18).These hydrophobic silicalite-1 membranes containing silane coupling agents effectively removed ethanol from 3 wt.%,5 wt.%and 10 wt.%aqueous ethanol solutions by pervaporation over a temperature range of 303-323 K.The separation factor(a) of ethanol decreased as the ethanol content in the feed solution increased from 3%to 10%whereas the permeation flux(J) basically remained constant.Ethanol separation factors(a) of 7.90-22.24 with total fluxes(J) of 0.76-2.89 kg/(m^2h) were obtained by pervaporation at 3_3-323 K for ethanol feed composition of 3%-10%.展开更多
Three types of composite PDMS membranes were prepared by using PAN, CA, and PVDF as support materials and used to separate ethanol from aqueous solution by pervaporation.The experimental results evidently demonstrated...Three types of composite PDMS membranes were prepared by using PAN, CA, and PVDF as support materials and used to separate ethanol from aqueous solution by pervaporation.The experimental results evidently demonstrated that the support layer had a significant impact on the flux and selectivity of composite PDMS membranes. The effect of the average pore size of supports on the performance of composite PDMS membranes was complex, and depended on many factors such as the physico-chemical properties of skin layers or supports and the preparation methods of composite membranes. The total flux of ethanol-water mixture through each composite PDMS membrane increased with increasing temperature. In contrast, the relation between selectivity and temperature was different due to various supports. With increasing feed concentration, the flux through each composite PDMS membrane increased quickly while the selectivity decreased.All these observation would be helpful to provide a guideline for the selection of an optimum support layer.展开更多
基金the National Natural Science Foundation of China under Grant No.50972103the Scientific Research Foundation for Returned Overseas Chinese Scholars,Ministry of Education of China
文摘A multi-layer mesoporous silicalite-1 membrane supported on commercially available porous alumina tubes was prepared by firstly dip-coating the tubes in silica colloid sol and then using a hydrothermal synthetic process.The mesoporous silicalite-1 membrane was further modified by grafting organosilane compounds with various alkyl chains length(C_nH_(2n+1)(CH_3)_2SiCl;n = 1,3,8,12 and 18).These hydrophobic silicalite-1 membranes containing silane coupling agents effectively removed ethanol from 3 wt.%,5 wt.%and 10 wt.%aqueous ethanol solutions by pervaporation over a temperature range of 303-323 K.The separation factor(a) of ethanol decreased as the ethanol content in the feed solution increased from 3%to 10%whereas the permeation flux(J) basically remained constant.Ethanol separation factors(a) of 7.90-22.24 with total fluxes(J) of 0.76-2.89 kg/(m^2h) were obtained by pervaporation at 3_3-323 K for ethanol feed composition of 3%-10%.
文摘Three types of composite PDMS membranes were prepared by using PAN, CA, and PVDF as support materials and used to separate ethanol from aqueous solution by pervaporation.The experimental results evidently demonstrated that the support layer had a significant impact on the flux and selectivity of composite PDMS membranes. The effect of the average pore size of supports on the performance of composite PDMS membranes was complex, and depended on many factors such as the physico-chemical properties of skin layers or supports and the preparation methods of composite membranes. The total flux of ethanol-water mixture through each composite PDMS membrane increased with increasing temperature. In contrast, the relation between selectivity and temperature was different due to various supports. With increasing feed concentration, the flux through each composite PDMS membrane increased quickly while the selectivity decreased.All these observation would be helpful to provide a guideline for the selection of an optimum support layer.
