Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

ABSTRACT

The work presented focused on the experimental data of the activity coefficients at infinite dilution of several solutes in ionic liquid of 1-butyl-3-methylimidazolium dicyanamide, [BMIM][DCA]. The values of activity coefficient at infinite dilution for 64 solutes, including alkanes, cycloalkanes, alkenes, alkynes, aromatic hydrocarbons, alcohols, water, ethers, ketones, acetonitrile, pyridine, 1-nitropropane, thiophene, and esters in [BMIM][DCA] were determined by gas liquid chromatography at six temperatures in range of (318.15 368.15) K. The gas-liquid partition coefficients were calculated for all solutes. The partial molar excess Gibbs energy, enthalpy and entropy at infinite dilution were calculated from the experimentalactivity coefficient at infinite dilution values. The [BMIM][DCA] was discussed as a solvent for the different types of separation problems with special attention to the separation of hexane/hex-1-ene, cyclohexane/cyclohexene and ethylbenzene/styrene. This work discuss a particular type of mixture made up of small hydrocarbons (alkanes) and their unsaturated counterparts (alkenes). The separating ability of the investigated ionic liquid was compared with the previously investigated 1-butyl-3-methylimidazolium-based, and dicyanoamide-based ILs for three chosen separation problems. Additionally, a literature review of activity coefficient at infinite dilution for the hexane/hex-1-ene separation problem at T = 323.15 K is presented for the years 2010 2015. It was found that several ILs may replace conventional solvents. The proposed [BMIM][DCA] may be used as an alternative solvent for the separation of alkenes from alkanes.