Pervaporation performance for ethanolwater mixtures by silicalite-1 filled PDMS membranes
Ultra-fine silicalite-1 particles were modified with two kinds of chlorosilanes (dodecyltrichlorosilane and octyltrichlorosilane)and characterized with FI-IR，TGA，contact angle measurements and BET analysis. It was found that the surface hydrophobicity of silicalite-1 particles was improved significantly，with contact angle increasing from 16.4°(unmodified silicalite1)to 122.0°(modified silicalite-1 with dodecyltrichlorosilane). Modified silicalite-1 particles were incorporated into PDMS (poly (dimethylsiloxanediol))membranes，which were applied for the pervaporation of ethanol/water mixtures. The effect of zeolite loading and operation conditions on pervaporation performance of the membranes was investigated in detail. 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 sorption and diffusion selectivity of filled membranes were also measured to explain the pervaporation properties of silicalite-1 filled PDMS membranes. It was found that modification of silicalite1 with dodecyltrichlorosilane effectively improved the sorption 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 of the high separation factor and sorption selectivity indicated that modification of silicalite-1 with chlorosilanes was an effective method to improve the selectivity of the zeolite filled PDMS membranes for ethanol/water mixtures.
醇水体系 膜分离技术 沸石分子筛 渗透汽化性能 硅橡胶膜 填充改性
ZHAN Xia LI Jiding CHEN Jian HUANG Junqi
Membrane Technology & Engineering Research Center, Department of Chemical Engineering,Tsinghua Unive Membrane Technology & Engineering esearch Center, Department of Chemical Engineering,Tsinghua Univer
国内会议
北京
英文
150-158
2008-12-01（万方平台首次上网日期，不代表论文的发表时间）