Inflection in the loading dependence of the Maxwell-Stefan diffusivity of iso-butane in MFI zeolite

被引：37

作者：

Chmelik, C. ^{[2
]}

Heinke, L. ^{[2
]}

Kaerger, J. ^{[2
]}

Schmidt, W. ^{[3
]}

Shah, D. B. ^{[4
]}

van Baten, J. M. ^{[1
]}

Krishna, R. ^{[1
]}

机构：

[1] Univ Amsterdam, Vant Hoff Inst Mol Sci, NL-1018 WV Amsterdam, Netherlands

[2] Univ Leipzig, Abt Grenzflachenphys, D-04103 Leipzig, Germany

[3] Max Planck Inst Coal Sci, D-45470 Mulheim, Germany

[4] Cleveland State Univ, Dept Chem & Biomed Engn, Cleveland, OH 44115 USA

来源：

CHEMICAL PHYSICS LETTERS | 2008年 / 459卷 / 1-6期

关键词：

D O I：

10.1016/j.cplett.2008.05.023

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Configurational-bias Monte Carlo simulations of the adsorption isotherm for iso-butane (iC4) in MFI zeolite shows a strong infection at a loading Theta = 4 molecules per unit cell. The consequence of the isotherm inflection on the loading dependence of the Maxwell-Stefan (M-S) diffusivity, D, was investigated using infra-red microscopy (IRM). The experimental data show that D decreases nearly linearly as H is increased to 4; further increase in H results in a sharp increase in D, with a cusp at Theta = 4. Kinetic Monte Carlo (KMC) simulations are used to rationalize the experimental observations. The simulations indicate that significant inter-molecular repulsions are present for Theta > 4. (c) 2008 Elsevier B. V. All rights reserved.

引用

页码：141 / 145

页数：5

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