Prediction of viscosity and surface tension properties of aqueous solution of ionic liquids EMIES

Abstract

1-Ethyl-3-methylimidazolium ethyl sulfate (EMIES) was synthesized by using N-methylimidazole and diethyl sulfate as raw materials, the density, viscosity and surface tension of aqueous EMIES with various concentrations were measured in the temperature range from 288.15 to 328.15 K. According to the Jones-Dole empirical equation, the viscosity B-coefficients were calculated. Using the empirical equation of the relationship between Δμ2≠0 and T, the activation entropy (ΔS2≠0) and activation enthalpy (ΔH2≠0) were further obtained, the viscosity values of aqueous EMIES were predicted by using the Eyring semiempirical equation, which were highly consistent with experimental values of the viscosity. Furthermore, on the basis of the traditional Eӧtvӧs empirical equation, the new Eӧtvӧs equation was further derived by using the linear relationship between the molar surface Gibbs energy (gs) and temperature, each parameter has the definite physical meaning and a new unit of energy in new Eӧtvӧs equation. The predicted values of the surface tension of aqueous EMIES were obtained by the definition of the molar surface Gibbs energy, which were highly consistent with the experimental values of the surface tension.