Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

ABSTRACT

The activity coefficients at infinite dilution, gamma13, for 61 solutes, including alkanes, cycloalkanes, alkenes, alkynes, aromatic hydrocarbons, alcohols, water, thiophene, ethers, ketones, esters, aldehyde, acetonitrile, pyridine and 1-nitropropane in the ionic liquid (IL) 1-butyl-1-methylmorpholinium tricyanomethanide, [BMMOR][TCM] were determined by gas liquid chromatography at six temperatures within the range of (318.15 to 368.15) K. The thermodynamic functions at infinite dilution as partial molar excess Gibbs free energy DGE1 , enthalpy DHE1 , and entropy term TrefDSE1 were calculated from the experimental gamma13 values obtained over the temperature range. The density of [BMMOR][TCM] was measured over the temperature range (288.15 to 368.15) K. The gas liquid partition coefficient KL was calculated for all solutes. The values of selectivity and capacity for a few separation problems such as hexane/benzene, cyclohexane/benzene, heptane/thiophene at T = 328.15 K were calculated from c1 13 and compared to literature values for similar ionic liquids, viz. N-methyl-2-pyrrolidinone (NMP), and sulfolane. In comparison with the previously measured values for [BMPYR][TCM], the morpholinium IL presents high selectivity for the separation of aromatic hydrocarbons from aliphatic hydrocarbons, and especially thiophene, or piridine from heptane with a slightly lower capacity. New data show that [BMMOR][TCM] IL may be proposed as an alternative solvent for the separation of sulphur or nitrogen compounds from alkanes.