Thermodynamic study of binary mixtures of 2-propanol with ionic liquids, 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, 1-hexyl-3-methylimidazolium trifluoromethanesulfonate and triethylhexylammonium bis(trifluoromethylsulfonyl)imide

Abstract

In this work, densities, speeds of sound, refractive indices and viscosities of three binary mixtures containing the ionic liquids 1-hexyl-3-methylimidazolium bis(trifluoromethyl-sulfonyl)imide, 1-hexyl-3-methylimidazolium trifluoromethanesulfonate and triethylhexyl-ammonium bis(trifluoromethylsulfonyl)imide, mixed with 2-propanol at wide temperature and composition ranges at atmospheric pressure have been measured. From these experimental data, the excess molar volume, excess molar compressibility, deviation in refractive index and deviation in viscosity have been calculated. Excess properties have been correlated with the composition data using Redlich-Kister polynomial equation. The effects of temperature, cation and anion of ionic liquid on the physicochemical properties were analysed and discussed in terms of intermolecular interactions occurring in the studied systems. The Prigogine-Flory-Patterson theory was examined for suitability for the correlation of excess molar volumes with compositions.