Permeation of hexane isomers across ZSM-5 zeolite membranes

被引:38
作者
Krishna, R [1 ]
Paschek, D [1 ]
机构
[1] Univ Amsterdam, Dept Chem Engn, NL-1018 WV Amsterdam, Netherlands
关键词
D O I
10.1021/ie990912d
中图分类号
TQ [化学工业];
学科分类号
0817 ;
摘要
Gump et al. (Ind. Eng. Chem. Res. 1999, 38, 2775) recently showed that extremely high selectivities are realized for the separation of normal hexane (n-C-6) from 2,2-dimethylbutane (22DMB) when these components are allowed to diffuse across a ZSM-5 zeolite membrane. Their reported selectivities for a 50-50 feed mixture was found to be about 2 orders of magnitude higher than that for the single components. Furthermore, at a temperature of 398 K, the flux of 22DMB exhibits a curious maximum with increasing partial pressure. The objective of this communication is to provide a theoretical background to their experimental observations. Configurational bias Monte Carlo (CBMC) simulations are used to calculate the pure component and mixture isotherms at various temperatures. The Maxwell-Stefan (MS) theory for zeolite diffusion is then used to calculate the fluxes for single-component and binary-mixture permeation. The combined CBMC-MS model provides a nearly quantitative explanation of the experimental data of Gump et al.
引用
收藏
页码:2618 / 2622
页数:5
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