Thermodynamics and activity coefficients at infinite dilution measurements for organic solutes and water in the ionic liquid 1-butyl-1-methylpyrrolidinium tetracyanoborate

The activity coefficients at infinite dilution, γ13∞, for 45 solutes, including alkanes, cycloalkanes, alkenes, alkynes, aromatic hydrocarbons, alcohols, thiophene, tetrahydrofuran, ethers, acetone, and water, in the ionic liquid 1-butyl-1-methylpyrrolidinium tetracyanoborate, [BMPYR][TCB], were determined by gas–liquid chromatography at temperatures from 318.15 K to 368.15 K. 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. The gas–liquid partition coefficients, KL were calculated for all solutes and the Abraham solvation parameter model was 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-ethyl-3-methylimidazolium tetracyanoborate, [EMIM][TCB], 1-decyl-3-methylimidazolium tetracyanoborate, [DMIM][TCB], and similar ionic liquids. The densities of [BMPYR][TCB] in temperatures range from 318.15 K to 368.15 K, the temperature of fusion and the enthalpy of fusion were measured.

► Measurements of activity coefficients at infinite dilution using GLC. ► Forty-five solvents in the IL 1-butyl-1-methylpyrrolidinium tetracyanoborate, [BMPYR][TCB]. ► Possible entrainer for different separation processes. ► The gas–liquid partition coefficients, KL were calculated. ► The Abraham solvation parameter model was discussed.