Liquid−liquid equilibria of three ternary systems, {glycerol + benzene + methanol}, {glycerol + benzene + ethanol}, and {glycerol + benzene + 1-propanol}, were measured at temperatures of (288.15, 298.15, and 308.15) K. The quality of the results was assured by the Othmer−Tobias and Hand equations with the linear correlation factor (R 2 > 0.98). The results were satisfactorily correlated with the UNIQUAC equation with total average deviations of 0.55 %, 0.69 %, and 0.42 %, respectively. Glycerol was demonstrated as a suitable solvent to separate the mixture of benzene and 1-propanol into each pure component, by combining two operations of conventional distillation and liquid extraction. ■ INTRODUCTIONSolvent extraction is an important separation technique for organic components. The operation requires reliable knowledge of the liquid−liquid equilibrium (LLE) between the mixture separated and the solvents selected. Because of strong polarity differences between molecular species of the mixture and those of the solvents, predictions of LLE are much more difficult than those of vapor−liquid equilibrium (VLE).Since VLE of three binary mixtures of {benzene + methanol}, {benzene + ethanol}, and {benzene + 1-propanol} produce azeotropic mixtures at atmospheric pressure, the mixtures cannot be separated into their constituents solely by conventional distillation.Glycerol is partially miscible with benzene but arbitrarily miscible with methanol, ethanol, and 1-propanol. In addition, it has a high normal boiling point (563.7 K) and a high density (1261.3 kg·m −3 at 293 K). 1 After extraction of each alcohol with glycerol, the elimination and recovery of residual glycerol from the alcohol solutions is carried out easily by vaporization or distillation.In this work, in order to determine the feasibility of glycerol as a solvent to eliminate each alcohol from benzene + alcohol solutions containing methanol, ethanol, and 1-propanol, the LLE of these three systems were measured at temperatures of (288.15, 298.15, and 308.15) K, and their phase diagrams were determined. As far as we know, the LLE of the {glycerol + benzene + ethanol} system has been measured at 298.15 K by McDonald, 2 but the LLE of the two other systems have not been studied.The experimental results were correlated with the universal quasichemical activity coefficient (UNIQUAC) equation. The correlation results were discussed. Distribution coefficients for alcohols and degree of selectivity were also investigated, combining the VLEs of the related binary mixtures at atmospheric pressure. ■ EXPERIMENTAL SECTIONChemicals. The organic reagents used (glycerol, benzene, methanol, ethanol, and 1-propanol) were purchased from Wako Pure Chemical Industries, Ltd., all of which were stated to be minimum assays of 99.5 mass %. After dehydrated with molecular sieves 4A, the reagents were used without further purification. Because both the mutual solubility of benzene and glycerol, which described later in Tables 1 to 3, and that of benzene and water are small amounts, the...
Liquid-liquid equilibria of three ternary systems {glycerol + acetone + water}, {glycerol + 1, 4-dioxane + water}, and {glycerol + acetonitrile + water} were measured at temperatures of 288.15, 298.15, and 308.15 K. The results of the first two systems were satisfactorily correlated with the UNIQUAC equation with average deviations of 0.74 and 0.81%, respectively. Those of the last system were well correlated with a deviation of 2.49%. Glycerol was verified as a suitable solvent to remove water from acetone + water and acetonitrile + water solutions, through investigation of the distribution coefficients and selectivity for water, combining vapor-liquid equilibria of the systems {acetone + water} and {acetonitrile + water} at atmospheric pressure.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.