Effect of the Alkyl Chain on the Physical Properties of Imidazolium-Based Ionic Liquids with 1-Propanol, 1-Butanol, and 1-Pentanol Binary Mixtures

Abstract

Viscosities and surface tensions were measured at temperatures of 298.15, 303.15, 308.15, and 313.15 K and a pressure of 101.3 kPa for 1,3-dimethyl and 1-ethyl-3-methyl imidazolium methylsulfates ([dmim][MeSO4] and [emim][MeSO4], respectively) with 1-alcohols (propanol, butanol, and pentanol) over the whole range of mole fractions. The corresponding deviation properties and excess Gibbs free energy were calculated using the experimental data. Furthermore, the Redlich–Kister polynomial was used to correlate excess and deviation properties. The measured viscosities of the binary systems under study were used to test the applicability of empirical models to binary systems involving ionic liquids. The effect of the alkyl chain of the two ionic liquids on the measured and calculated properties is discussed.