Mutual Solubility of Pyridinium-Based Tetrafluoroborates and Toluene

Abstract

Mutual solubilities of pyridinium-based tetrafluoroborates (namely, 1-butylpyridinium tetrafluoroborate, 1-butyl-2-methylpyridinium tetrafluoroborate, 1-butyl-4-methylpyridinium tetrafluoroborate, and 1-hexylpyridinium tetrafluoroborate) and toluene were obtained at (298.15, 318.15, and 338.15) K. The data were acquired by means of an experimental procedure utilizing gas chromatography and a gravimetric method. The results show that the liquid-liquid equilibrium in the studied systems is strongly asymmetrical. While the mole fraction solubility of the pyridinium-based ionic liquids in toluene ranges from 1.0 · 10 -5 to 5.2 · 10 -5 , the solubility of toluene in these ionic liquids varies from 0.318 to 0.579 in mole fraction. The experimental data were correlated with a semiempirical equation. Parameters of the nonrandom two-liquid (NRTL) equation were evaluated as well.

Promising Thiolanium Ionic Liquid for Extraction of Aromatics from Aliphatics: Experiments and Modeling

“…In agreement with other studies, , we show conclusively that some IL does dissolve in toluene, albeit a relatively small amount. This suggests that mixtures of ILs and toluene exhibit normal liquid–liquid phase equilibrium, as dictated by the minimization of the Gibbs free energy, resulting in two liquid phases that contain both components.…”

“…While this practice is prevalent in publications on the separation of aromatics and aliphatics using ILs, there have been significant efforts to determine IL solubility in some organic solvents, especially those relevant to the use of ILs for desulfurization. These measurements are carried out by methods such as cloud point or clear point observance, evaporation and residue analysis, chemiluminescence nitrogen analysis, and ion chromatography, in some cases demonstrating detection limits as low as 10 –10 mole fraction. − Still, a number of studies have characterized IL/aromatic liquid mixtures as clathrates, , where the IL/aromatic liquid clathrate phase exhibits “immiscibility with excess aromatic solvents” . Here, we made significant efforts to experimentally measure the concentration of the ILs in toluene and n -heptane using NMR spectroscopy.…”

Mutual Solubility of Aromatic Hydrocarbons in Pyrrolidinium and Ammonium-Based Ionic Liquids and Its Modeling Using the Cubic-Plus-Association (CPA) Equation of State

“…A database of experimental binary liquid–liquid equilibria (LLE) data of different ILs with a broad range of hydrocarbons has been reported. By inspection of the literature available in the Scopus database, most of the references (25) are related to mixtures containing imidazolium-based ILs, while scarce publications about the phase behavior of binary mixtures with ILs based on other cations such as ammonium (3), phosphonium (3), pyridinium (7), pyrrolidinium (6), or quinolinium (7) have been found. − Because of the large number of {aromatic hydrocarbon (1) + ionic liquid (2)} potential mixtures, new solubility studies are needed since the solubility of aromatic compounds in the ILs affects their use as extraction media.…”

Solubilities of Diethyl Phthalate, Dicyclopentadiene, and Styrene in Ionic Liquid 1-Ethyl-3-methylimidazolium Acetate

“…The NRTL activity coefficient model can be used to correlate the VLE or LLE data of nonideal systems . Many authors utilized NRTL model to correlate the LLE data for systems containing ionic liquids, and they found the correlation results agreed well with the experimental results. − ,− For example, Jongmans et al , correlated the binary and ternary LLE of the system ethylbenzene + styrene + pyridinium-based ionic liquids by the NRTL model. So in this work, the NRTL model was also used to correlate the experimental data.…”

“…So in this work, the NRTL model was also used to correlate the experimental data. Because the solubility of ionic liquid in organic-rich phase can be neglected, when the NRTL model was used to correlate experimental data, the IL content in the organic-rich phase was assumed to be x * = 0.0001, according to the study and the assumptions of other authors. − ,,,− The NRTL equation is as follows where T is the temperature (K); α ij is the nonrandomness parameter; and B ij is the binary interaction parameter (K).…”