Ternary liquid–liquid equilibrium data for n-Hexane-Benzene-DES (choline chloride/ethylene glycol, choline chloride/glycerol, choline chloride/urea) at 303 K and 101.3 kPa

In this study, deep eutectic solvents (DESs) were prepared using choline chloride as hydrogen bond acceptor (HBA) and ethylene glycol (EG) or glycerol (GLY) or urea (U) as hydrogen bond donor (HBD) and were evaluated as solvents in the extraction of benzene from n-hexane. Six of such solvents were prepared using different molar ratios of HBA: HBD and code named DES1, DES2, DES3, DES4, DES5 and DES6. Liquid–liquid equilibria (LLE) data for the ternary systems of n-hexane-benzene-DESs were measured at 303 K and 101.3 kPa. Solubility data and mutual solubilities between n-hexane and DES were measured using the traditional cloud point method. The tie lines were obtained using titration and refractive index measurements on both phases (n-hexane phase and DES-phases). The ternary systems exhibit type-1 phase behavior. The Othmer-Tobias and Hands equations were applied to examine the reliability of the LLE data. The tie-line data were correlated using the nonrandom two-liquid (NRTL) and universal quasichemical (UNIQUAC) thermodynamic models, and their corresponding binary interaction parameters were determined. The results show that the maximum separation factors were 31.24, 462.00, 15.24, 37.83, 174.60 and 126.00 for DES1, DES2, DES3, DES4, DES5 and DES6, respectively. The glycerol based DES (DES2 and DES5) show the highest separation factors and thus considered the most suitable for separating benzene from hexane. The regression coefficient for both Othmer-Tobias and Hand equations are higher than 0.99 for all DESs, indicating the reliability and consistency of the data. Both NRTL and UNIQUAC models adequately capture the experimental data.

The Research and Mechanism of Extracting Vitamin B6 Using Aqueous Two-Phase Systems

The aim of this work is to investigate the quaternary systems which contain (polyethylene glycol/isopropyl alcohol) + ethanol + salt (Na2SO4/Na2CO3) + water to understand their liquid-liquid equilibrium (LLE) and salting-out ability and apply them to definite uses. For this purpose, phase diagrams and liquid-liquid equilibrium (LLE) data of the investigated quaternary systems were experimentally determined at 308.15, 318.15, and 328.15 K. Binodal curves were fitted to three empirical nonlinear equations, whereas tie-lines were fitted to the Setschenow-type equation and another two-parameter equation. All the models were successfully correlated with the experimental data. What is more, factors such as temperature, different organic solvent, and type of salt are studied. It was demonstrated that temperature has no influence in binodal curves and the salting-out ability follows the order Na2CO3 > Na2SO4. Finally, we chose the best system (isopropyl alcohol + ethanol + Na2CO3 + H2O) to find out the extraction efficiency when dealing with vitamin B6. The results show that when the temperature is 308.15 K and pH is 5.02, the extraction efficient can reach a top level. It serves as a theoretical basis for the extraction, separation, and purification.

Liquid−Liquid Extraction of Linalool from Methyl Eugenol with 1-Ethyl-3-methylimidazolium Hydrogen Sulfate [EMIM][HSO4] Ionic Liquid

The liquid–liquid equilibrium (LLE) data for a ternary system {methyl eugenol + linalool +1-ethyl-3-methylimidazolium hydrogen sulfate [EMIM][HSO4]} (Meu-Lin-IL) were measured at 298.2 K and atmospheric pressure. The Othmer–Tobias correlation was used to verify the reliability of the experimental tie-line data. The solubility curves were obtained using the cloud point titration indicating the liquid-liquid equilibrium of the ternary system was in Type II class where two immiscible curve pairs were attained. Distribution coefficients, separation factors and selectivity were calculated for the immiscibility regions. The calculated results were compared with the experimental data. Characterization studies were performed by Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA) and proton nuclear magnetic resonance spectroscopy (1H-NMR) techniques.

Effects of the polymer molecular weight and type of cation on phase diagrams of polythylene glycol + sulfate salts aqueous two-phase systems

Phase diagrams and liquid ? liquid equilibrium (LLE) data for aqueous two-phase systems (ATPSs) containing zinc sulfate, magnesium sulfate or aluminium sulfate and polyethylene glycols PEG 300, 400 and 600 have been determined at 298.15 K. It was attempted to show how the PEG molecular weight and the type of cation influence the binodal curve, tie line length (TLL) and slope of the tie line (STL). The results have shown that as the PEG molecular weight increases, the two-phase region becomes extended and the binodal curve shifts to the origin. The refractive index and density of ternary (PEG 300,400 and 600 + zinc sulfate/magnesium sulfate/aluminium sulfate + water) systems have been measured to achieve the phase composition and the tie lines. Finally, the effective excluded volume (EEV) model was applied to describe the salting-out ability of the systems. The LLE data from this research may be potentially used for recovering biological molecules like proteins.

TERNARY LIQUID-LIQUID EQUILIBRIA FOR {BENZENE + CYCLOHEXANE + DIFFERENT IONIC LIQUIDS } at T= 298.2 K and P=1 atm: EFFECT OF CATION AND ANION ON SEPARATION PERFORMANCE.

Ionic liquids (ILs) based on imidazolium and pyridinium cations and differenttypes of anions containing transition metals were investigated for extraction of benzene from cyclohexane. The Liquid-liquid equilibrium (LLE) data are presented for six ternary systems of (Cyclohexane + Benzene + an ionic Liquid) at 298.15 K and atmospheric pressure. The ILs used in these systems are [Bmim][FeCl4], [Bmim][AlCl4], [Bmim][CuCl2], [BuPy][FeCl4]), [BuPy][AlCl4], and [C6Py][FeCl4] were all prepared in the lab. The influence of cation and anion structure of ILs on the separation selectivity and capacity for aliphatic/aromatic mixtures was analyzed. The results indicate that most ILs investigated shows both higher extractive selectivity and capacity for the aromatic components for the systems studied herein, suggesting they can be used as promising extracts for the separation of aliphatic/aromatic mixtures. The LLE data were well correlated by the non-random two-liquid (NRTL) model of non-electrolyte solutions with overall ARD deviation being about 0.0001 interm of the mole fraction based activity.