Comprehensive Evaluation of COSMO-RS for Predicting Ternary and Binary Ionic Liquid-Containing Vapor–Liquid Equilibria

Abstract

To develop efficient ionic liquid (IL)-based separation processes like extractive distillation, the knowledge of IL-involved vapor–liquid equilibria (VLE) is necessary. Since experimental measurements are usually time-consuming and expensive, reliable models for VLE prediction are highly desirable. In this work, the predictive performance of COSMO-RS is systematically evaluated for ternary and binary IL-containing VLE systems. A large experimental VLE database is established from the literature, including 6531 and 2265 data points for ternary and binary systems, respectively. The ternary and binary VLE systems are divided into five and three subsets based on the varieties of molecular solutes. The COSMO-RS performance in capturing the effects of IL and solute structures, IL dosage, and temperature on VLE is analyzed. COSMO-RS provides generally qualitative and in some cases quantitative description of the VLE behaviors and thus could be used as a valuable tool for prior IL screening and process analysis for related separations.

Computer-Aided Molecular Design of Ionic Liquids as Advanced Process Media: A Review from Fundamentals to Applications

“…Similar extensive assessments of COSMO-RS for predicting the vapor–liquid equilibria (VLE) and LLE of binary {IL + molecular compound} systems, mutual solubility of water and IL, excess enthalpy of monoethanolamine and ILs, solute-in-IL activity coefficient, etc. have also been conducted, ,− generally showing that the COSMO-based activity coefficient models could provide qualitatively good and quantitatively acceptable predictions in many cases. Consequently, they have become popular tools for IL screening and design tasks wherever thermodynamic properties need to be considered. − …”

Condensable Gases Capture with Ionic Liquids

“…The COSMO-RS model developed by Klamt et al is a predictive thermodynamic model that integrates the electrostatic theory of local charge interaction on the molecular surface and the statistical thermodynamic methodology. − It can predict the thermodynamic equilibrium relationship of fluid and liquid mixture, including vapor–liquid equilibrium (VLE), liquid–liquid equilibrium (LLE), solid–liquid equilibrium (SLE), solubility, distribution coefficient, activity coefficient, Henry’s constant, saturated vapor pressure, excess enthalpy, acidity value (p K a ), flash point, density, viscosity and other thermodynamic properties of pure components or mixtures . COSMO-RS model is an effective apriori tool for screening suitable ILs for gas separation processes, which is independent of the experimental data and only depends on the molecular structure information on the target system.…”

Economic Analysis and Life Cycle Environmental Assessment of Imidazolium-Based Ionic Liquids for Separation of the Methanol/Dimethyl Carbonate Azeotrope

“…Extensive experimental VLE data and interaction parameters were published in the field of thermodynamics. Second is extension of a UNIFAC or COSMO model in ternary or binary IL-containing VLE systems, such as UNIFAC-Lei, − UNIFAC-IL, COSMO-RS, − and COSMO-UNIFAC . At present, group definition, group parameters, and group interaction parameters of the UNIFAC-Lei model have been proved to be reliable for process simulation. − Third is use of CAMD methods based on predicting models for screening of ILs with excellent performances. , At the process unit level, many works have used process simulation, analysis, synthesis, optimization, and control tools to verify the industrial feasibility and economic performances of IL processes. − Aspen Plus software based on the NRTL or UNIFAC-Lei model is often used in process simulations.…”