Physiochemical study of 1-methyl imidazole trifluoro methane sulfonate ionic liquid in aqueous and aqueous amino acid solutions at different temperatures

Abstract

The experimental density and speed of sound of 1-methyl imidazole trifluoro methane sulfonate ionic liquid in aqueous binary ([MIm][OTf]+H2O) solution and aqueous ternary ([MIm][OTf] + 0.05 mol.kg−1 aqueous glycine) solution are reported in the dilute concentration range (0.06 to 0.16 mol.kg−1) at the temperature between 288.15 and 318.15 K with 5K interval and at atmospheric pressure. These density (ρ) and speed of sound (u) data are utilized to derive various significant thermophysical parameters namely apparent molar volume of solute (Vϕ), isentropic compressibility of solution (κs) and apparent molar isentropic compressibility of solute (KS,ϕ). The limiting apparent molar volume (Vϕ0) and limiting apparent molar isentropic compressibility (KS,ϕ0) of [MIm][OTf] are estimated by extrapolation methods. By using Vϕ0and KS,ϕ0data of the studied binary and ternary systems, the values of transfer volumes i.e. volume changes due to transfer (ΔtrVϕ0)and transfer compressibility i.e. compressibility changes due to transfer(ΔtrKsϕ0) from aqueous to aqueous amino acid solution are estimated. The observed ΔtrVϕ0and ΔtrKsϕ0values are temperature dependent. The outcomes of this investigation are framed within the context of solute-solute and solute-solvent interactions.