Activity Coefficients at Infinite Dilution of Organic Solutes in 1-Ethyl-3-methylimidazolium Tetrafluoroborate Using Gas−Liquid Chromatography

Abstract

The activity coefficients at infinite dilution, γ i ∞, for 25 organic solutes, alkanes, alkenes, alkyl benzenes, acetonitrile, acetone, 1,4-dioxane, tetrahydrofuran, ethyl acetate, and chloromethanes, in the ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF4]) have been measured by the gas−liquid chromatographic method at temperatures from (303.15 to 363.15) K. The partial molar excess enthalpies at infinite dilution, H i E,∞, of the solutes in the ionic liquid were also derived from the temperature dependence of the γ i ∞ values.

Activity coefficients at infinite dilution of organic solutes in the ionic liquid 1-ethyl-3-methylimidazolium tetracyanoborate [EMIM][TCB] using gas–liquid chromatography

“…The values of selectivity for the separation of {hexane(i)/benzene(j) + cyclohexane(i)/ benzene(j)} at T = 298.15 K using different ILs with cation [EMIM] + and five anions are taken from the literature [2,11,12,19,37]. The results of the present work are listed in …”

Activity Coefficients at Infinite Dilution and Physicochemical Properties for Organic Solutes and Water in the Ionic Liquid 1-Ethyl-3-methylimidazolium trifluorotris(perfluoroethyl)phosphate

“…This can be seen in Fig. 2 [ 10 , 11 , 14 , 18 , 21 , 22 , 29 – 39 ]. The reason for this is that the longer the non-polar alkyl chain, the stronger will be the van der Waals interactions with hexane and benzene, thus reducing the difference between IL-hexane and IL-benzene selectivities.…”

“…

Fig. 2 Comparison of selectivity, S 12 ∞ , at T = 328.15 K for hexane/benzene separation problem of different 1-alkyl-3-methylimidazolium ionic liquids: ( filled circle ) [FAP] − this work and [ 22 ], ( empty circle ) [FAP] − [ 21 , 22 ], ( empty square ) [NTf 2 ] − [ 10 , 29 – 31 ]; ( empty triangle ) [TCB] − [ 11 , 32 , 33 ], ( filled triangle ) [CF 3 SO 3 ] − [ 14 , 34 , 35 ], ( filled square ) [BF 4 ] − [ 18 , 36 – 39 ], where alkyl = n -C n H 2 n +1 . The lines are drawn to guide the eye

Fig.

…”

Separation of benzene and thiophene with a mixture of N -methyl-2-pyrrolidinone (NMP) and ionic liquid as the entrainer

“…Among these ILs, [EMIM] + [BF 4 ] À has one of the highest selectivity. The comparison between the predicted benzene capacity by COSMO-RS model and the experimental data obtained from references [45][46][47][48][49][50][51][52] at infinite dilution in ILs at T = 298.15 K is shown in Fig. 2(b), indicating the accuracy of COSMO-RS in qualitative analysis.…”