Predicting the Solubility of CO₂ in Toluene + Ionic Liquid Mixtures with PC-SAFT

Abstract

Perturbed-chain statistical associating fluid theory (PC-SAFT) was applied for modeling the vapor−liquid equilibrium of CO 2 + toluene + ionic liquid (IL) mixtures and the molar volume of their liquid phases at temperatures between 298.15 K and 333.15 K and at pressures up to 80 bar. ILs used for this study contain the bis-(trifluoromethylsulfonylimide) anion ([Tf 2 N] − ) and imidazolium, pyridinium, thiolanium, and phosphonium cations. The pure-IL PC-SAFT parameters were fit to pure-IL liquid density data. Temperaturedependent binary interaction parameters were fit to binary liquid−liquid equilibrium data (i.e., toluene + IL) obtained from the literature and some points measured for this work. Temperature independent binary interaction parameters were fit to vapor−liquid equilibrium data (CO 2 + IL, CO 2 + toluene) from the literature. The availability of the pure-IL parameters and binary interaction parameters allowed prediction of CO 2 solubility in toluene + IL mixtures with an absolute average relative deviation (AARD) of 6.8%, as well as molar volumes of CO 2 + toluene + IL mixtures with an AARD of 5.0%, for the four ternary systems under investigation.

Promising Thiolanium Ionic Liquid for Extraction of Aromatics from Aliphatics: Experiments and Modeling

“…These parameters are commonly fit to pure-component density data. Additionally, one binary k ij parameter was fit for each IL + aromatic and IL + aliphatic pair, which was consistent with our previous work . No k ij was used for the completely miscible toluene + heptane mixture.…”

“…PC-SAFT parameters used here were obtained from previous works and are shown in Table S4. ,, ILs were considered as self-associating compounds and toluene and heptane as nonpolar. Other contributions, such as polar for ILs or quadrupolar for the aromatics, were set to zero since they usually do not improve the calculations compared with their associating and nonpolar representation, respectively. , Binary parameters k ij were fit to binary liquid–liquid equilibrium data of aromatic + IL and heptane + IL at 298.15 K and 1.013 bar.…”

“…Besides the general parameters needed to define pseudocomponents in Aspen, such as density and molecular weight, molecular volume and sigma profiles are needed to calculate LLE with the COSMO-SAC method. Density was calculated by fitting experimental densities at different temperatures. − Molecular volumes and sigma profiles used for COSMO-SAC were the same as those generated for the COSMO-RS model.…”

Combining soft-SAFT and COSMO-RS modeling tools to assess the CO2–SO2 separation using phosphonium-based ionic liquids

“…In a different approach, Camper et al [35] and Scovazzo et al [36] measured the solubility of CO2 in several ILs (i.e., including [P6, 6,6,14][Cl]) and modeled their results with regular solution theory. Finally, the version of PC-SAFT was used by Canales et al [37] to model gas solubility in toluene + [P2,2,2,8][NTf2].…”

Structure and Dynamics of an Ionic Liquid Mixture Film Confined by Mica

“…Ionic liquids (ILs) have unique chemical and physical properties that make them excellent candidates for various applications in chemical synthesis, catalysis, lubrication, and electrochemistry, among other areas, and they can be designed with specificity for particular problems. − The design for particular purposes needs not be restricted to the combination of a single cation with a single anion, and many studies have gone beyond this by considering mixtures with conventional solvents or multiple ions. Significant research has recently been devoted to binary and ternary mixtures of ILs. − Because this is relevant to applications, when dealing with multiple salt components, we are not only interested in their bulk behavior but also in their preferential arrangement at interfaces.…”