A Thermodynamic and Physical Study on (1-Hexyl-3-methylimidazolium Chloride + 1-Pentanol and Ethylene Glycol) Binary Mixtures at Temperatures (293.15–333.15) K

Abstract

Densities, ρ, viscosities, η, and refractive indices, n D, for 1-hexyl-3-methyl imidazolium chloride ([hmim]Cl) (IL), 1-pentanol, and ethylene glycol (EG), and for the binary mixtures {x 1[hmim]Cl + x 21-pentanol} and {x 1[hmim]Cl + x 2EG} were measured over the entire composition range at temperatures (293.15–333.15) K and ambient pressure. The excess molar volumes, $$ V_{\text{m}}^{\text{E}} $$ , and viscosity deviations, Δη, for the binary mixtures were calculated from the experimental data. The $$ V_{\text{m}}^{\text{E}} $$ values of {x 1[hmim]Cl + x 21-pentanol} mixtures are negative over the entire composition range at all temperatures, and increase with increasing temperature in the alcohol rich region and decrease with increasing temperature in the IL rich range. The $$ V_{\text{m}}^{\text{E}} $$ values of {x 1[hmim]Cl + x 2EG} mixture are positive in the alcohol rich range and negative in the IL rich range at all temperatures, and decrease with increasing temperature. Viscosity deviations of both mixtures are negative over the entire composition range at all temperatures and decrease with increasing temperature. The excess molar properties were correlated by Redlich–Kister equation, and the excess molar volumes were correlated using the PFP model. The fitting parameters and standard deviations were determined.