Thermophysical properties of pure 1-ethyl-3-methylimidazolium methylsulphate and its binary mixtures with alcohols

Abstract

The density and surface tension of 1-ethyl-3-methylimidazolium methylsulphate, [EMIM][CH 3SO 4] ionic liquid have been measured from (283.15 to 333.15) K. The coefficient of thermal expansion was calculated from the experimental density results using an empirical correlation for T = (283.15–338.15) K. Molecular volume and standard entropies of [EMIM][CH 3SO 4] ionic liquid were obtained from the experimental density values. The surface properties, critical temperature and enthalpy of vaporization were also discussed. Density and surface tension have been measured over the whole composition range for [EMIM][CH 3SO 4] with alcohols (methanol, ethanol, 1-butanol) binary systems at 298.15 K and atmospheric pressure. Excess molar volumes and surface tension deviations for the binary systems have been calculated and were fitted to a Redlich–Kister equation to determine the fitting parameters and the root mean square deviations.