Infinite Dilution Activity Coefficients of Solutes Dissolved in Two Trihexyl(tetradecyl)phosphonium Ionic Liquids

Infinite dilution activity coefficients (y(1,2)(infinity)) are reported for 31 and 40 diverse organic solutes dissolved in trihexyl(tetradecyl)phosphonium L-lactate and trihexyl(tetradecyl)phosphonium (1S)-(+)-10-camphorsulfonate, as determined by inverse gas chromatography at temperatures from 323 K to 373 K. The measured retention data were further transformed to gas-to-ionic liquid and water-to-ionic liquid partition coefficients using standard thermodynamic expressions based upon measured values for corresponding gas-to-water partition coefficients of the test solutes. Both sets of partition coefficients were interpreted using an ion-specific equation coefficient form of the basic Abraham general solvation parameter model. Finally, ion-specific equation coefficients were calculated for the chiral L-lactate and (1S)-(+)-10-camphorsulfonate anions.