Physicochemical properties of aqueous solution of 1-methylimidazolium acetate ionic liquid at several temperatures

摘要

Densities (ρ) and viscosities (η) of 1-methylimidazolium acetate ([Mim]Ac) protic ionic liquid + water mixture were measured at T = (293.15, 298.15, 303.15, 308.15 and 313.15) K under atmospheric pressure. Refractive in-dices (n _D) and electrical conductivities (κ) of the above-mentioned system over the entire composition range were measured at 298.15 K. Excess molar volumes (V~E), viscosity deviations (Δη) and refractive index deviations (Δn _D) were obtained from the experimental data and ?tted to the Redlich-Kister equation with satisfactory re-sults. The results show that V~E values of the system are negative over the whole composition range, whereas Δη and Δn _D values are positive. Other volumetric properties such as apparent molar volumes (V_(фi)), partial molar volumes (V _(m;i)) and excess partial molar volumes (V_(m;i)~E) of the system were calculated from the density data. The concentration dependence of κ was ?tted according to the empirical Casteel-Amis equation. The measured and derived properties were employed to investigate the intermolecular interactions of the system.