Activity coefficients at infinite dilution measurements for organic solutes and water in the ionic liquid 1-ethyl-3-methylimidazolium tetracyanoborate

Research highlights: → Measurements of activity coefficients at infinite dilution using GLC. → 36 organic solvents and water in the ionic liquid 1-ethyl-3-methylimidazolium tetracyanoborate, [EMIM][TCB]. → Possible entrainer for different separation processes. → The partial molar excess thermodynamic functions at infinite dilution were calculated. - Abstract: The activity coefficients at infinite dilution, γ13∞, for 36 solutes, including alkanes, cycloalkanes, alkenes, alkynes, aromatic hydrocarbons, alcohols, thiophene, tetrahydrofuran, ethers, acetone, and water, in the ionic liquid 1-ethyl-3-methylimidazolium tetracyanoborate, [EMIM][TCB], were determined by gas-liquid chromatography at temperatures from 298.15 K to 358.15 K. These values are compared to those previously published for selected solutes in the same ionic liquid. The values of the partial molar excess Gibbs free energy ΔG1E,∞, enthalpy ΔH1E,∞, and entropy ΔS1E,∞ at infinite dilution were calculated from the experimental γ13∞ values obtained over the temperature range. Three gas-liquid partition coefficients, KL were calculated for all solutes and the Abraham solvation parameter model is discussed. The values of the selectivity for different separation problems were calculated from γ13∞ and compared to literature values for N-methyl-2-pyrrolidinone (NMP), sulfolane, 1-decyl-3-methylimidazolium tetracyanoborate, [DMIM][TCB], and additional ionic liquids.