In this work, the ionic liquid trihexyltetradecylphosphonium dicyanamide [P-6 6 6 14][DCA] was evaluated as a potential extraction solvent for organic compounds. The assessment was done based on the solute retention data obtained by gas liquid chromatography (GLC) for 33 solutes: (alkanes, alkenes, ketones, alcohols, alkynes, aromatic hydrocarbons, tetrahydrofuran, thiophene, acetonitrile and water). The experiment was conducted at a series of four temperatures (313.15-343.15) K at 10 K intervals. Experimental activity coefficients at infinite dilution data acquired over the investigated temperature range was then utilized to compute the thermodynamic functions at infinite dilution including partial molar excess enthalpy, Delta H-1(E, infinity) , Gibbs free energy, Delta G(1)(E, infinity) and entropy term, T-ref Delta S-1(E, infinity). The selectivity and capacity values for some of the separation challenges (heptane/thiophene, water/butanol and heptane/benzene) were computed from the gamma(infinity)(13) data and in contrast to the other phosphonium based ionic liquids in the literature. The selectivity and capacity data shows that the investigated ionic liquid can be utilized in the separation of heptane/thiophene or water/butan-l-ol mixtures. (C) 2019 Elsevier B.V. All rights reserved.