Determination of Activity Coefficients at Infinite Dilution of Organic Solutes in the Ionic Liquid 1‑(2-Hydroxyethyl)-3-methylimidazolium Nonafluoro-1-butanesulfonate Using Gas–Liquid Chromatography

Activity coefficients at infinite dilution (γ_<i>i</i>^∞) for a variety of organic solutes (alkanes, cycloalkanes, alkenes, alkyl benzenes, alcohols, 1,4-dioxane, acetone, acetonitrile, tetrahydrofuran, chloroform, and dichloromethane) in the ionic liquid (IL) 1-(2-hydroxyethyl)-3-methylimidazolium nonafluoro-1-butanesulfonate ([C₂OHmim]­[C₄F₉SO₃]) have been determined by gas–liquid chromatography using the IL as the stationary phase. The measurements were conducted in the temperature range from 303 to 353 K. The partial molar excess Gibbs energies (Δ<i>G</i>_<i>i</i>^E,∞), enthalpies (Δ<i>H</i>_<i>i</i>^E,∞), and entropies (Δ<i>S</i>_<i>i</i>^E,∞) at infinite dilution of the solutes in the ionic liquid were calculated from the temperature dependence of the values of γ_<i>i</i>^∞. Values of selectivity <i>s</i>_<i>ij</i>^∞ and capacity <i>k</i>_<i>j</i>^∞ at <i>T</i> = 323.15 K for the IL [C₂OHmim]­[C₄F₉SO₃] were calculated for both cyclohexane/benzene and benzene/methanol binary systems. The results obtained from this work were compared with reported literature data for other [C₂OHmim] based ILs