Phase Equilibria Study of the Binary Systems (N-Butyl-4-methylpyridinium Tosylate Ionic Liquid + Organic Solvent, or Water)

Abstract

Solid + liquid) equilibria (SLE) and (liquid + liquid) equilibria (LLE) for the binary systems ionic liquid (IL) N-butyl-4-methylpyridinium tosylate (p-toluenesulfonate) [BMPy][TOS] + an alcohol (1-butanol, or 1-hexanol, or 1-octanol, or 1-decanol), or water, or an alkane (hexane, heptane, octane), or benzene, or an alkylbenzene (toluene, ethylbenzene, propylbenzene), or tetrahydrofuran (THF) have been determined at ambient pressure. A dynamic method was used over a broad range of mole fractions and temperatures from (320 to 390) K. In the case of systems (IL + alkane, or alkylbenzene), the mutual immiscibility with an upper critical solution temperature (UCST) was detected. UV spectroscopy was used to determine the very small compositions of the IL in the alkanes, benzene, and alkylbenzenes (about 1 • 10 -5 IL mole fraction). For the binary systems containing alcohol and water, simple eutectic diagrams were observed with complete miscibility in the liquid phase. As usual, with increasing chain length of the alcohol, the solubility decreases. The basic thermal properties of the pure IL, i.e., melting and glass-transition temperatures as well as the enthalpy of fusion, have been measured using a differential scanning microcalorimetry technique (DSC). Well-known UNIQUAC, Wilson, and NRTL equations have been used to correlate experimental SLE data sets for alcohols and water. For the systems containing immiscibility gaps (IL + alkane, or benzene, or alkylbenzene, or tetrahydrofuran), parameters of the LLE correlation equations have been derived using only the NRTL equation.

(Solid+liquid) and (liquid+liquid) phase equilibria measurements and correlation of the binary systems {tri-iso-butyl(methyl)phosphonium tosylate+alcohol, or +hydrocarbon}

“…The left-hand limits of the equilibrium curves in this system and many others [9,[11][12][13][14][15][16][17][18] are very close to zero mole fraction of the IL, that is x 1 = 10 −4 to 10 −5 . These data were calculated previously for some ILs by COSMO-RS [11] within x 1 = 10 −4 to 10 −5 in hexane, benzene and alkylbenzenes as x 1 = 10 −5 [34]. The shape of the equilibrium curve was similar for every measured system.…”

Phase equilibria study of the binary systems (ionic liquid+thiophene): Desulphurization process

“…Compound [25]. b Calculated as for a hypothetical sub-cooled liquid by the group contribution method described by Barton [26].…”

Phase equilibria study of the binary systems (N-butyl-3-methylpyridinium tosylate ionic liquid+an alcohol)

“…The strong interaction between the IL and alcohols and the complete miscibility in the liquid phase were observed for ethanol and 1-propanol and also in all alcohols up to 1-dodecanol [25]. The complete miscibility in the liquid phase in the alcohols tested is the result of the strong interaction between dissimilar molecules as hydrogen bonding, or/and n-p interaction between the polar groups of the IL and the solvent.…”

“…Usually, the activity coefficients at infinite dilution [1,5,6], SLE and LLE of binary, or ternary systems containing the IL and an alcohol, or water, or ether, or ketone, or hydrocarbon have been measured by us [1,7,12,14,19]. This paper is a continuation of our wide ranging investigation into ILs containing the tosylate anion [19,[25][26][27]. Determination of activity coefficients at infinite dilution of organic solutes in the ionic liquid, N-butyl-4-methylpyridinium tosylate, [BMPy][TOS] by gas-liquid chromatography (GLC) has been reported [26].…”

“…The [BMPy][TOS] was investigated by us as a separation medium for aromatic and aliphatic hydrocarbons, with moderate selectivities and capacities [26]. The LLE and SLE data of {[BMPy][TOS] + an alcohol (1-butanol, or 1-hexanol, or 1-octanol, or 1-decanol), or water, or an alkane (hexane, heptane, and octane), or benzene, or an alkylbenzene (toluene, ethylbenzene, and propylbenzene) or tetrahydrofuran (THF) have been published indicated that this ionic liquid can be used as a solvent in the extraction processes in different separating processes [25]. In the case of systems (IL + alkane, or alkylbenzene) the mutual immiscibility with an upper critical solution temperature (UCST) was detected.…”