Density, conductivity, viscosity, and excess properties of (pyrrolidinium nitrate-based Protic Ionic Liquid + propylene carbonate) binary mixture

Abstract Density, ρ , viscosity, η , and conductivity, σ , measurements of binary mixtures containing the pyrrolidinium nitrate Protic Ionic Liquid (PIL) and propylene carbonate (PC), are determined at the atmospheric pressure as a function of the temperature from (283.15 to 353.15) K and within the whole composition range. The temperature dependence of both the viscosity and conductivity of each mixture exhibits a non-Arrhenius behaviour, but is correctly fitted by using the Vogel–Tamman–Fulcher (VTF) equation. In each case, the best-fit parameters, such as the pseudo activation energy, E a ∗ and ideal glass transition temperature, T 0 are then extracted. The excess molar volumes V E , and viscosity deviations from the ideality, Δη , of each investigated mixture were then deduced from the experimental results, as well as, their apparent molar volumes, V ϕ , thermal expansion coefficients α p , and excess Gibbs free energies (Δ G ∗ E ) of activation of viscous flow. The V E , α p E , Δη values are negative over the whole composition range for each studied temperature therein. According to the Walden rule, the ionicity of each mixture was then evaluated as a function of the temperature from (283.15 to 353.15) K and of the composition. Results have been then discussed in terms of molecular interactions and molecular structures in this binary mixture.