Liquid–liquid extraction of p-xylene from their mixtures with alkanes using 1-butyl-1-methylmorpholinium tricyanomethanide and 1-butyl-3-methylimidazolium tricyanomethanide ionic liquids

Abstract

Liquid – liquid experimental data for four ternary systems {1-butyl-1-methyl-morpholinium tricyanomethanide, [BMMOR][TCM], or 1-butyl-3-methylimidazolium tricyanomethanide, [BMIM][TCM] + p-xylene + octane, or decane} were determined at T = 298.15 K and atmospheric pressure. The separation of p-xylene from alkanes (octane, or decane) is performed by extraction with the tricyanomethanide - based ionic liquids. Good miscibility of p-xylene and practical complete immiscibility of alkanes in ionic liquids have been observed. Selectivity, S and solute distribution ratio, β at constant temperature for these mixtures were calculated and discussed. These parameters derived from the experimental equilibrium data were compared with the values for other ionic liquids available in the literature. The NRTL and UNIQUAC models were used to correlate experimental LLE data. Agreement between experimental and correlated data was satisfactory. The influence of the cation structure of the ionic liquid on the phase equilibrium and the separation ability of these ionic liquids was discussed. Additionally, the water content and basic physicochemical properties, such as: density, ρ and dynamic viscosity, η were determined for pure ILs at wide temperature range at ambient pressure.