Solute–solvent interactions of glycine, l-alanine, and l-valine in aqueous 1-methyl imidazolium chloride ionic liquid solutions in the temperature interval (288.15 to 308.15) K

Abstract

In the present study, volumetric and acoustic methods have been used to interpret intermolecular interactions of amino acids (glycine, l-alanine, and l-valine) in aqueous solutions of an ionic liquid, 1-methyl imidazolium chloride [mim][Cl] as a function of temperature. The density, ρ and speed of sound, c of glycine, l-alanine and l-valine in aqueous 1-methyl imidazolium chloride solutions have been measured in the temperature interval T=(288.15 to 308.15)K and atmospheric pressure. Then apparent molar volume (Vϕ) and apparent molar adiabatic compressibility (Kϕ,s) of these mixtures at the investigated temperatures have been calculated. The standard partial molar volumes (Vϕ0), standard partial molar volumes of transfer (ΔVϕ0), standard partial molar adiabatic compressibility (Kϕ,s0), and standard partial molar adiabatic compressibility (ΔKϕ,s0) of transfer have also been determined for these amino acid solutions. The results have been discussed in terms of interactions existing among solute and solvent. Also, the temperature dependence of the apparent molar volume has been used to calculate apparent molar expansivity ϕE0 and Hepler’s constant ∂2Vϕ0/∂T2, to verify the conclusions obtained from volumetric and speed of sound properties.