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

The activity coefficients at infinite dilution, gamma(similar to)(13), 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 Delta G(1)(E infinity), enthalpy Delta H-1(E infinity) and entropy Delta H-1(E infinity) at infinite dilution were calculated from the experimental gamma(infinity)(13) values obtained over the temperature range. Three gas-liquid partition coefficients, K-L 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 gamma(infinity)(13) and compared to literature values for N-methyl-2-pyrrolidinone (NMP), sulfolane, 1-decy1-3-methylimidazolium tetracyanoborate, [DMIM][TCB], and additional ionic liquids. (C) 2011 Elsevier Ltd. All rights reserved.