The use of ionic liquids for separation of binary hydrocarbons mixtures based on gamma infinity data measurements

• Published in: The Journal of chemical thermodynamics 2018-12, Vol.127, p.95-105
• Main Authors: Domańska, U., Karpińska, M.
• Format: Article
• Language: English
• Subjects: [N2,2,2,8][FSI] and [BMPyr][FSI]; Activity coefficients at infinite dilution; Ionic liquids; Separation; Thermodynamics
• ISSN: 0021-9614; 1096-3626
• DOI: 10.1016/j.jct.2018.07.024

[Display omitted] •ILs in separation of hydrocarbons.•Limiting activity coefficients measurements using GLC.•Selectivity and capacity of separation with [N2,2,2,8][FSI] and [BMPyr][FSI].•The gas-liquid partition coefficients, KL at infinite dilution.•The fundamental thermodynamic functions at infinite dilution. The effect of interactions between 64 organic solvents and water on the interfacial and bulk properties at infinite dilution of two ionic liquids (ILs) namely N-triethyl-N-octylammonium bis(fluorosulfonyl)imide, [N2,2,2,8][FSI] and 1-butyl-3-methylpyrrolidynium bis(fluorosulfonyl)imide, [BMPyr][FSI] were determined via measurement of activity coefficients γ13∞ at infinite dilution using the gas-liquid chromatography technique. Measurements were undertaken at six temperatures, in 10 K intervals, in the range of (318.15 to 368.15) K. The solutes studied included both non-polar and polar compounds, as alkanes, alkenes, and alkynes, as well as aromatic hydrocarbons, alcohols, water, ethers, ketones, pyridine, thiophene, esters, acetonitrile and 1-nitropropane. The gas-liquid partition coefficients, KL at infinite dilution, and the fundamental thermodynamic functions, partial molar excess Gibbs energy, enthalpy and entropy at infinite dilution were calculated from the experimental data measurements. The values of selectivity and capacity for four important in petrochemical technology separations, viz. hexane/hex-1-ene, hexane/benzene, cyclohexane/cyclohexene, and cyclohexane/benzene were calculated from γ13∞ values and compared to literature data for ammonium ILs with different cations and anions and for ILs with [BMPyr]− cation and different anions. The results from the study indicate that [N2,2,2,8][FSI] reveals not satisfied selectivity values in comparison with [BMPyr][FSI] and literature values for all four of the separation cases studied.