Volumetric, compressibility and viscosity studies of binary mixtures of [EMIM][NTf2] with ethylacetate/methanol at (298.15–323.15) K

Abstract

Densities, speeds of sound and viscosities of pure and binary mixtures 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([EMIM][NTf2])+ethyl acetate/methanol have been measured experimentally over the entire composition range and at six temperatures from 298.15K to 323.15K, at pressure 0.1MPa using Anton Paar Density and Sound velocity meter DSA 5000M and, Lovis microviscometer 2000M. From these experimental data, the excess molar volumes (VE), viscosity deviations (∆η) and isentropic compressibility deviations (∆κs) have been evaluated. The VE values are negative for [EMIM][NTf2]+ethyl acetate system upto x1=0.90 and positive above this x1 value at all temperatures of study. However, the VE values are negative for [EMIM][NTf2]+methanol system at entire mole fraction range and at all temperatures. The VE values in both studied systems decrease with increase in temperature. The ∆η and ∆κs are found to be negative over the entire range of mole fraction and decrease with increasing temperature in both binary systems. The computed data of VE, ∆η and ∆κs have been correlated with Redlich-Kister polynomial equation. The measured and computed data have been interpreted in terms of ion-dipole, ion-ion and dipole-dipole interactions and structural effects between like and unlike molecules upon mixing. The experimental data of VE have also been used to examine the applicability of Prigogine–Flory–Patterson (PFP) theory in predicting the VE of the binary mixtures. The minimum and maximum percent deviations of experimental and calculated by PFP VE values are 0.017 and 3.01 for [EMIM][NTf2]+ethyl acetate and 1.19 and 2.10 for [EMIM][NTf2]+methanol systems, respectively.