PERVAPORATION SEPARATION OF ETHANOL/WATER MIXTURES WITH CHLOROSILANE MODIFIED SILICALITE-1/PDMS HYBRID MEMBRANES  

作　　者：李继定 

机构地区：[1]Membrane Technology & Engineering Research Center,Department of Chemical Engineering,Tsinghua University

出　　处：《Chinese Journal of Polymer Science》2010年第4期625-635,共11页高分子科学（英文版）

基　　金：supported by the Major State Basic Research Program of China(No.2009CB623404);National Natural Science Foundation of China(Nos.20736003,20676067);National High Technology Research and Development Program of China(Nos.2007AA06Z317,2008EG111021);Foundation of Ministry of Education of China (No.20070003130);Foundation of the State Key Laboratory of Chemical Engineering(SKL-ChE-08A01)

摘　　要：Ultra-fine silicalite-1 particles were modified with four kinds of chlorosilanes （dodecyltrichlorosilane, octyltrichlorosilane, hexadecyltrichlorosilane and octadecyltrichlorosilane） and characterized by FI-IR, TGA, contact angle measurements and BET analysis. It was found that the surface hydrophobicity of silicalite-1 particles was improved significantly as the alkyl group was strongly bonded to the particle surface. Modified silicalite-1 particles were incorporated into PDMS （poly（dimethylsiloxanediol）） membranes, which were applied for the pervaporation separation of ethanol/water mixtures. The effect of surface properties, zeolite loading and operation conditions on pervaporation performance of the membranes was investigated. The separation factor of PDMS membranes filled with modified silicalite-1 increased considerably compared with that filled with unmodified ones, and the total flux decreased with increasing zeolite loading. The solution and diffusion selectivity of hybrid membranes were also measured to explain the pervaporation properties of silicalite-1 filled PDMS membranes. It was found that modification of silicalite-1 with dodecyltrichlorosilane effectively improved the solution and diffusion selectivity of silicalite-1 filled PDMS membranes with high zeolite loading. This may be attributed to the high surface hydrophobicity of modified silicalite-1 and its good integration with PDMS membranes. Both the high separation factor and solution selectivity indicated that modification of silicalite-1 with chlorosilanes was an effective method to improve the selectivity of silicalite-1/PDMS hybrid membranes for ethanol.Ultra-fine silicalite-1 particles were modified with four kinds of chlorosilanes （dodecyltrichlorosilane, octyltrichlorosilane, hexadecyltrichlorosilane and octadecyltrichlorosilane） and characterized by FI-IR, TGA, contact angle measurements and BET analysis. It was found that the surface hydrophobicity of silicalite-1 particles was improved significantly as the alkyl group was strongly bonded to the particle surface. Modified silicalite-1 particles were incorporated into PDMS （poly（dimethylsiloxanediol）） membranes, which were applied for the pervaporation separation of ethanol/water mixtures. The effect of surface properties, zeolite loading and operation conditions on pervaporation performance of the membranes was investigated. The separation factor of PDMS membranes filled with modified silicalite-1 increased considerably compared with that filled with unmodified ones, and the total flux decreased with increasing zeolite loading. The solution and diffusion selectivity of hybrid membranes were also measured to explain the pervaporation properties of silicalite-1 filled PDMS membranes. It was found that modification of silicalite-1 with dodecyltrichlorosilane effectively improved the solution and diffusion selectivity of silicalite-1 filled PDMS membranes with high zeolite loading. This may be attributed to the high surface hydrophobicity of modified silicalite-1 and its good integration with PDMS membranes. Both the high separation factor and solution selectivity indicated that modification of silicalite-1 with chlorosilanes was an effective method to improve the selectivity of silicalite-1/PDMS hybrid membranes for ethanol.

关 键 词：SILICALITE-1 PDMS membrane MODIFICATION Pervaporation. 

分 类 号：TB383.2[一般工业技术—材料科学与工程]