文献类型：期刊文献

英文题名：Simplified critical-point criteria for some multicomponent systems

作者：Cai, Jun[2];Hu, Ying[2];Prausnitz, John M.[1,3]

机构：[1]Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA;[2]E China Univ Sci & Technol, Dept Chem, Shanghai 200237, Peoples R China;[3]Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA

年份：2010

卷号：65

期号：8

起止页码：2443

外文期刊名：CHEMICAL ENGINEERING SCIENCE

收录：;EI(收录号：20101012749122);WOS:【SCI-EXPANDED(收录号:WOS:000276468200002)】；

基金：For financial support. JC and YH are grateful to the National Natural Science Foundation of China (no. 20973062), the Ministry of Education of China, 111 project (B08021) and to PCSIRT; JMP is grateful to the Office for Basic Sciences, US Department of Energy.

语种：英文

外文关键词：Continuous thermodynamics; Critical property; Critical-point criteria; Polydisperse mixture

摘要：Stability theory for multicomponent fluid mixtures is used to calculate the spinodal and the critical locus for a multicomponent mixture. Upon using well-defined simplifying assumptions, the criteria developed here are suitable for mixtures whose properties are described by a molecular-thermodynamic model where the Helmholtz energy depends on composition-average model parameters. Such mixtures are typically encountered in systems that contain homologues. Our method is especially useful when the homologue-mixture contains a large number of components. Different from our previous work (Fluid Phase Equilibria, 206, 41-59, 2003), the criteria developed here do not require that the model parameters depend on moments of a characteristic property (e.g. molecular weight) used to characterize the distribution of components. The spinodal lines and the critical points obtained by our method are identical to those obtained from the less-computer-efficient Gibbs traditional method. To illustrate, the Soave-Redlich-Kwong equation of state is used to calculate critical properties of mixtures containing carbon dioxide, hydrogen sulphide, and alkanes. (C) 2009 Elsevier Ltd. All rights reserved.