Critical Properties, Normal Boiling Temperatures, and Acentric Factors of Fifty Ionic Liquids

Abstract

The critical properties, the normal boiling temperatures, and the acentric factors of ionic liquids have been determined using an extended group contribution method based on the well-known concepts of Lydersen and of Joback and Reid. The critical properties of ionic liquids cannot be experimentally determined in many cases since most of these compounds start to decompose as the temperature approaches the normal boiling point. However, for the development of thermodynamic models either for pure components or for mixtures containing ionic liquids, the critical properties and other physical parameters are required. The so-called group contribution methods have been commonly used to estimate the critical properties of many substances for which these properties are not available, but no attempt has been made to estimate the critical properties of ionic liquids, as presented in this study. The method does not require any additional data besides the knowledge of the structure of the molecule and its molecular weight. Since experimental critical properties of ionic liquids are not available, the accuracy of the method is checked by calculating the liquid densities of the ionic liquids considered in the study. The results show that the values determined for the critical properties, for the normal boiling temperatures, and for the acentric factors are accurate enough for engineering calculations, for generalized correlations, and for equation of state methods, among other applications.

Modeling vapor liquid equilibrium of ionic liquids + gas binary systems at high pressure with cubic equations of state

“…The critical properties of ionic liquids were taken from Valderrama et al (2007Valderrama et al ( , 2008aValderrama et al ( , 2009), Ren et al (2010) and Nwosu et al (2009). For CO 2 , C 2 H 6 and CHF 3 , the properties were taken from the DIPPR data base (DIADEM, 2000).…”

Extraction of free fatty acids from soybean oil using ionic liquids or poly(ethyleneglycol)s

“…After such assumptions, the critical parameters and acentric factor for AMOENG100 were obtained applying the modified Lydersen-Joback-Reid method given by Valderrama and Robles. [37][38][39] For the ionic liquid [bmim][DCA], these values were taken directly from literature. 37 In the case of PEG200, PEG400, soybean oil, and fatty acids the boiling point, critical temperature and pressure were calculated using the method of Gani and coworkers 40,41 as in the case of other substances of high molar masses.…”

Phase Behavior at High Pressure of the Ternary System: CO2, Ionic Liquid and Disperse Dye

“…The binary interaction parameters in the mixing rules were optimized using the P, x data for each system. The critical properties and acentric factors of the IL were obtained of the Valderrama and Robles [30], and the critical properties, and acentric factors of the disperse dye Red 60 were obtained of the Mishima et al [31]. The critical properties are presented in Table 4 and Table 5 shows the interaction parameters for each system.…”