Measurements and correlations of electrolytic conductivity and molar heat capacity for the aqueous ionic liquid systems containing [Emim][EtSO 4] or [Emim][CF 3SO 3

Abstract

New data on electrolytic conductivity, κ, and molar heat capacity, C P, for aqueous solutions of ionic liquids, 1-ethyl-3-methylimidazolium ethylsulfate [Emim][EtSO 4] and 1-ethyl-3-methylimidazolium trifluoromethanesulfonate [Emim][CF 3SO 3] obtained using a commercial conductivity meter and differential scanning calorimeter were reported here for temperature up to 353.2 K. The estimated measurement uncertainties for κ and C P were 1 and 2%, respectively. The present κ and C P data were reported as functions of temperature and composition. A modified empirical equation was used to correlate the temperature and composition dependence of the present κ data. An excess molar heat capacity, C P E , expression using the Redlich–Kister type equation for the latter’s temperature and composition dependence was used to represent the measured C P and C P E of the considered solvent systems. The applied correlations represented the κ and C P measurements satisfactorily as indicated by an overall average deviation of 1.9 and 0.1%, respectively.