Ternary Liquid–Liquid Equilibrium of Azeotropes (Water +2-Propanol) with Ionic Liquids ([Dmim][NTf₂]) at Different Temperatures

Abstract

The liquid–liquid equilibrium (LLE) of a ternary system of water (H2O) + 2-propanol + 1-decyl-3-methylimidazolium bis­(trifluoromethylsulfonyl)­imide ([Dmim]­[NTf2]) ionic liquid was measured in the temperature range from 278.15 to 298.15 K at atmospheric pressure. The distribution coefficient and selectivity were calculated to determine the influence of the temperature on the LLE. The results indicate that a decrease in temperature reduces the solubility of H2O in [Dmim]­[NTf2] and increases the immiscibility region of the ternary phase diagram. The experimental data were correlated using the nonrandom two liquid and the universal quasichemical models, and the critical properties for [Dmim]­[NTf2] were determined.

Liquid–Liquid Equilibrium of Isobutyl Acetate + Isobutyl Alcohol + Imidazolium-Based Ionic Liquids at 298.15 and 308.15 K

“…From Figures 5 and 6, as the temperature increases, the distribution coefficient and selectivity decrease slightly, Meanwhile, in Figures 1−4, as the solubility increases with the temperature increasing, the area of the heterogeneous region in the ternary phase diagrams decreased. Xu et al 27 explored the LLE for (water +2-Propanol + [Dmim][NTf 2 ]) at different temperatures. In their work, the experimental results indicate that two-phase region also decreased with the increasing temperature.…”

Explorations of Liquid–Liquid Phase Equilibrium for the Mixture (Isopropanol + Water) with Pyridinium-Based Ionic Liquids

“…To recover IPA by liquid–liquid extraction, the extractant selection has been reported in some literatures, for instance, organic solvents, − deep eutectic solvents, , and ionic liquids (ILs). − ILs have been applied in the separation field due to their superiority in designability, thermal stability, and negligible vapor pressure. − Cumplido et al − performed the liquid–liquid equilibrium (LLE) exploration for the mixture water + IPA with different imidazolium-based ILs at temperatures of 283.2–323.2 K. All the used ILs played a positive role in recovering IPA from the azeotropic mixture. Liu et al determined the LLE behavior for water + IPA with the ILs 1-hexyl-3-methyl imidazolium bis­(trifluoromethylsulfonyl)­imide ([Hmim]­[NTf 2 ]), 1-octyl-3-methyl imidazolium bis­(trifluoromethylsulfonyl)­imide ([Omim]­[NTf 2 ]), and 1-decyl-3-methyl imidazolium bis­(trifluoromethylsulfonyl)­imide ([Dmim]­[NTf 2 ]) at 298.15 K. The results demonstrated that the ionic liquid with the longer alkyl chain length exhibited a strong ability to recover IPA.…”

“…Liu et al determined the LLE behavior for water + IPA with the ILs 1-hexyl-3-methyl imidazolium bis­(trifluoromethylsulfonyl)­imide ([Hmim]­[NTf 2 ]), 1-octyl-3-methyl imidazolium bis­(trifluoromethylsulfonyl)­imide ([Omim]­[NTf 2 ]), and 1-decyl-3-methyl imidazolium bis­(trifluoromethylsulfonyl)­imide ([Dmim]­[NTf 2 ]) at 298.15 K. The results demonstrated that the ionic liquid with the longer alkyl chain length exhibited a strong ability to recover IPA. The LLE behavior reported for the systems (water + IPA + [Dmim]­[NTf 2 ]) and (water + IPA + tetrabutylammonium dicyanamide) , revealed that the extraction capacity of the ILs decreased with increasing the temperature. Meanwhile, the pyridinium-based ILs have been used for the separation of cyclohexane, benzene, toluene, and nitrogen compounds and have shown good prospects in the applications of extraction processes.…”

“…18−23 ILs have been applied in the separation field due to their superiority in designability, thermal stability, and negligible vapor pressure. ) and (water + IPA + tetrabutylammonium dicyanamide) 22,23 revealed that the extraction capacity of the ILs decreased with increasing the temperature. Meanwhile, the pyridinium-based ILs have been used for the separation of cyclohexane, 27 benzene, 28 toluene, 29 and nitrogen compounds 30 and have shown good prospects in the applications of extraction processes.…”

Salts Effect on Isobaric Vapor–Liquid Equilibrium for the Azeotropic Mixture 2-Propanol + Water

“…2-Propanol is a basic chemical widely used in industry as a solvent or as a chemical intermediate because of its excellent physical and chemical properties. − Separation of the aqueous mixture of 2-propanol is often demanded in its production and recovery, which is also conducive to environmental protection. The mixture of 2-propanol and water forms a minimum boiling point azeotrope at atmospheric pressure .…”