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In this work we studied the applicability of four imidazolium-based ionic liquids (ILs) with different allyl-, or benzyl-substituents and bis(trifluoromethylsulfonyl)imide, or dicyanamide anions in the separation of hex-1-ene/hexane and cyclohexene/cyclohexane compounds. Experimental values for liquid–liquid equilibrium (LLE) were obtained for various binary and ternary mixtures of {IL (1) + hex-1-ene (2) + hexane (3)} or {IL (1) + cyclohexene (2) + cyclohexane (3)} at T = 298.15 K and p = 0.1 MPa. The ILs studied were as follows: 1-allyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [AMIM][NTf 2 ], 1-allyl-3-methylimidazolium dicyanamide, [AMIM][DCA], 1-benzyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [BzMIM][NTf 2 ], 1-benzyl-3-methylimidazolium dicyanamide, [BzMIM][DCA]. These ILs were chosen after the analysis of the selectivities calculated from the limiting activity coefficients data. The results are useful for the design an industrial process of extraction. The dicyanamide-based ILs showed excellent results in terms of selectivity, but bis(trifluoromethylsulfonyl)imide-based ILs revealed twice better solute distribution ratio. The chromatography analysis revealed that the ILs used as an entrainers were not present in the hydrocarbon-rich layer, which is convenient for production process, because eliminates the step needed for the separation of the solvent. The [AMIM][DCA] showed suitable extractive properties to replace nowadays methods of separation for hex-1-ene/hexane and cyclohexene/cyclohexane compounds. All experimental data were correlated with the NRTL model. The experimental tie-lines were calculated in good agreement with each other. [ABSTRACT FROM AUTHOR]

In this manuscript, densities, ρ , speeds of sound, u , and viscosities, η for binary mixtures of 1-butyl-3-methylimidazoliumbis(trifluoromethylsulfonyl)imide([C 4 mim][NTf 2 ]) with molecular organic solvents (MOS) namely butyl acetate (BAC), butan-1-amine (BAM) and butanal (BAL) were measured at entire range of compositions. The measurements were collected at atmospheric pressure and temperature ranges from (298.15 to 323.15) K. The excess molar volumes, V m E , excess molar isentropic compressibilities, K S , m E , and logarithm of viscosity, ln η m were derived from measured values of densities, ρ , speeds of sound, u , and viscosity, η , respectively. The V m E , K S , m E and ln η m were correlated using Redlich–Kister polynomial equation. The non-ideal behaviour of these binary mixtures was discussed in light of temperature, nature of molecular organic solvent, structural effect and extent of molecular interactions exist in the binary mixtures. The V m E and K S , m E were negative and decrease with increasing temperature. The experimental V m E were reviewed by Prigogine–Flory–Patterson (PFP) theory. [ABSTRACT FROM AUTHOR]

Ionic liquids are neoteric, environmentally friendly solvents (as they do not produce emissions) composed of large organic cations and relatively small inorganic anions. They have favorable physical properties, such as negligible volatility and a wide range of liquid existence. (Liquid + liquid) equilibrium (LLE) data for systems including ionic liquids, although essential for the design, optimization and operation of separation processes, remain scarce. However, some recent studies have presented ternary LLE data involving several ionic liquids and organic compounds such as alkanes, alkenes, alkanols, ethers and aromatics, as well as water. In this work, the ASOG model for the activity coefficient is used to predict LLE data for 25 binary and 07 ternary systems at 101.3 kPa and several temperatures; all the systems are formed by ionic liquids including the bis[(trifluoromethyl)sulfonyl]imide (NTf 2 ) anion plus alkanes, alkenes, cycloalkanes, alkanols, water, thiophene and aromatics. New group interaction parameters were determined using a modified Simplex method, minimizing a composition-based objective function of experimental data obtained from the literature. The results are satisfactory, with rms deviations of approximately 3%. [ABSTRACT FROM AUTHOR]

Highlights: [•] Physicochemical characteristics of two 1-alkyl-1-methylpyrrolidinium ILs. [•] Similarities and differences between pyrrolidinium and imidazolium imides. [•] Volume and surface properties of [BMPyr][NTf2]+methanol or+acetonitrile. [•] Some properties of mixtures with [BMPyr][NTf2] and [BMIM][NTf2] are very close. [ABSTRACT FROM AUTHOR]