文献类型：期刊文献

英文题名：Modeling pVT properties and phase equilibria for systems containing ionic liquids using a new lattice-fluid equation of state

作者：Xu, Xiaochun[1]; Peng, Changjun[1]; Liu, Honglai[1]; Hu, Ying[1]

机构：[1] State Key Laboratory of Chemical Engineering, Department of Chemistry, East China University of Science and Technology, Shanghai 200237, China

年份：2009

卷号：48

期号：24

起止页码：11189

外文期刊名：Industrial and Engineering Chemistry Research

收录：EI(收录号：20100112615950)

语种：英文

外文关键词：Carbon dioxide - Equations of state - Phase equilibria - Binary mixtures - Thermodynamic properties

摘要：The cations or anions of ionic liquids (ILs) usually have long alkyl chains or chainlike structures. Therefore, ILs can be reasonably considered as fluids containing neutral chainlike molecules. Lattice-based molecular thermodynamic models generally used for polymer systems can be applied to describe the thermodynamic properties and phase behavior of IL systems. In our previous work, a new lattice-fluid equation of state (LF EoS) was developed and successfully applied to normal fluid systems (Xu et al., Fluid Phase Equilib. 2008, 265, 112.). In this work, this LF EoS is further extended to model the pVT properties and phase equilibria of IL systems. The molecular parameters of ILs in this EoS were determined by correlating the experimental pVT data of pure ILs. It is shown that the pVT behavior of IL mixtures can be fairly well predicted by these parameters. The vapor-liquid equilibria (VLE) of binary IL-solvent systems were calculated by using an adjustable binary parameter, k12. For liquid-liquid equilibria (LLE) of binary IL systems, a parameter Cr describing the effect of the mixture composition on the chain-length parameter r is further used, and satisfactory correlation is obtained. The upper critical solution temperature (UCST) can be predicted successfully. Moreover, the EoS reproduces the solubility data for carbon dioxide (CO2) in various ILs covering a wide range of pressures (0-100 MPa), and it describes the global behavior of trifluoromethane (CHF3) and IL mixtures. The results reveal that the LF EoS is well-suited for the calculation or prediction of the thermodynamic properties of systems containing ILs. ? 2009 American Chemical Society.