THERMODYNAMIC MODELING OF AZEOTROPIC MIXTURES WITH [EMIM][TfO] WITH CUBIC-PLUS-ASSOCIATION AND CUBIC EOSs

Abstract Ionic liquids (ILs) are organic salts that are liquids at room temperature and have low vapor pressure. These characteristics render ILs potential substitutes of organic solvents and inorganic salts in separation of azeotropic mixtures. This work presents vapor-liquid equilibrium modeling of the azeotropic mixture acetone + methanol + 1-ethyl-3-methylimidazolium-trifluoromethanesulfonate and ethanol + water + 1-ethyl-3-methylimidazolium-trifluoromethanesulfonate with the Cubic-Plus-Association Equation of State (CPA EoS). The azeotropic ternary mixture phase behavior was properly predicted using binary interaction parameters that were adjusted from binary mixture phase equilibrium data. Results show that the CPA EoS provides a better description of experimental data as compared to the Peng-Robinson-Wong-Sandler Equation of State (PRWS EoS).