Vapor Pressure Osmometry, Volumetry, and Compressibility Properties for Solutions of Several Imidazolium Based Ionic Liquids in (Glycine + Water) Solutions

Abstract

In this study, the effect of glycine on the thermodynamic properties of aqueous solutions containing ionic liquids 1-butyl-3-methylimidazolium chloride, [C 4 mim]Cl, 1-hexyl-3-methylimidazolium chloride, [C 6 mim]Cl, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, [C 4 mim][CF 3 SO 3 ], has been studied. For this purpose, first with help of the vapor pressure osmometery (VPO) method the water activity measurements have been performed on the ternary aqueous systems of (glycine + [C 4 mim]Cl, [C 6 mim]Cl, and [C 4 mim][CF 3 SO 3 ]) at T = 308.15 K. The influence of the IL nature on the vapor− liquid equilibria behavior of the investigated systems has been studied. The VPO measurements of these solutions show that due to the unfavorable IL-glycine interactions, the negative deviations from the semi-ideal state and in conclude the soluting-out effects have been observed in these solutions. The soluting-out phenomena appears by aqueous biphasic system formation in the case of aqueous [C 4 mim][CF 3 SO 3 ] + glycine system and precipitation of the glycine from the solution in the case of ternary [C 4 mim]Cl/[C 6 mim]Cl + glycine + water systems. In the second part of this work, density and sound velocity of solutions of the ILs in pure water and aqueous glycine solutions have been measured at four different temperatures. These data were used to obtain the apparent molar volume, V ϕ , isentropic compressibility, K ϕ , and those in the infinite dilution.

Thermodynamic Study of Ionic Liquids 1-Hexyl-3-methylimidazolium Halide with Methanol Mixtures

“…To the best of our knowledge, extensive measurements have been conducted on various properties, including density, viscosity, and enthalpy of mixing, for the systems comprising the imidazolium-based ILs and the molecular solvents such as H 2 O and organic solvents. ,− However, the majority focused on the dilute concentrations when studying the properties of imidazolium halide and molecular solvent systems, − and limited research covers the entire concentration range. − More specifically, Gómez et al determined the viscosities and densities of (ILs (i.e., [C n mim]Cl, n = 4, 6, 8) + H 2 O) over the entire compositional range at temperatures ranging from 298.15 to 343.15 K; Sastry et al measured the densities of (ILs (i.e., [C n mim][halide], n = 4, 6, 8) + H 2 O) at temperatures of 298.15 and 308.15 K; Yan et al determined the viscosities and densities of (ILs (i.e., [C n mim]Cl, n = 2, 4, 6, 8) + N , N -dimethylformamide) at temperatures ranging from 288.15 to 318.15 K. These three studies mainly focus on the investigation of the effects of carbon chain length on the properties of (IL + cosolvent) systems; Yang et al measured the densities and viscosities of ([C 6 mim]Cl + different organic solvents (i.e., N , N -dimethylacetamide, N , N -dimethylformamide, dimethyl sulfoxide, and pyridine)), investigating the effects of organic solvents on the viscosity of the mixtures. Additionally, the previous research suggests that enthalpies of mixing are significantly changed with the IL anions, especially the halide ions.…”

Partitioning of l-Tryptophan in Aqueous Biphasic Systems Containing an Alkylimidazolium Ionic Liquid and a Phosphate Salt

“…Figures – illustrate the good performance of the ePC-SAFT for the binaries considered in our work. The calculated ARD values as well as the sources of used experimental data − for the densities, the mean ionic activity coefficients, and the activity of water are given in Table S15 (SI).…”

Modeling Osmotic Coefficients in Aqueous Solutions of 1-Alkyl-3-methylimidazolim Halides: A Theory That Reflects the Electrical Structure of Ions and ePC-SAFT

“…Applying this version of the model, we introduced association between the cations and anions of ILs to take into account ion pairing, as suggested in ref . The model parameters for water are taken from ref and for Cl – and Br – from ref ; parameters for systems with [C n mim] + are regressed from the data on densities (refs − and data of this work given in Table S2) and osmotic coefficients of [C n mim]X ( n = 4, 6, 8, X = Cl, Br) aqueous solutions. All data sets are limited to 298.15 K.…”

“…The association term a assoc has not been included in our applications of this version of the model. The model parameters for water are taken from ref ; parameters for Cl – and Br – are regressed from data on densities, − mean ionic activity coefficients (MIAC), and osmotic coefficients of KCl and KBr aqueous solutions; and parameters for [C n mim] + are from data on densities (refs − and data of this work given in Table S2) and osmotic coefficients of [C n mim]X ( n = 4, 6, 8, X = Cl, Br) aqueous solutions.…”