The activity coefficients at infinite dilution, gamma(infinity)(13) for 65 solutes, including wide spectra of alkanes, alkenes and alkynes as well as aromatic hydrocarbons, alcohols, water, ethers, ketones, acetonitrile, pyridine, 1-nitropropane, thiophene, and esters in the 1-butyl-4-cyanopyridinium bis{(trifluoromethyl)sulfonyl}imide [BCN4Py][NTf2] were determined by gas-liquid chromatography for all solutes at seven temperatures in range of (308.15 to 368.15) K. The gas-liquid partition coefficients, K-L at infinite dilution and the fundamental thermodynamic functions, the partial molar excess Gibbs energy, Delta G(1)(E,infinity), enthalpy Delta H-1(E,infinity), and entropy term T-ref Delta S-1(E,infinity) were calculated. The values of selectivity and capacity for four separation problems as hexane/hex-1-ene, hexane/benzene, cyclohexane/cyclohexene and ethylobenzene-styrene were calculated from gamma(infinity)(13) and compared to literature values for bis{(trifluoromethyl) sulfonyl} imide-based ionic liquids (ILs) for the same separation problems. In comparison with the former measured ILs, the [(BCNPy)-Py-4] [NTf2] present quite high selectivity for the chosen separation problems, and an average capacity for hex-1-ene, benzene, cyclohexene and styrene. The data presented here shows that [(BCNPy)-Py-4][NTf2] may be proposed as an alternative solvent for the chosen separation problems in new technological projects. (C) 2016 Elsevier Ltd. All rights reserved.