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

Abstract

Vapor−liquid equilibrium (VLE) data for the systems 2-propanol + water + calcium chloride, 2-propanol + water + magnesium chloride, 2-propanol + water + calcium nitrate, and 2-propanol + water + magnesium nitrate were measured at the pressure of 101.3 kPa. Experimental data of all ternary systems passed the thermodynamic consistency test by modified McDermott−Ellis method. Then, the effects of salts on the vapor phase mole fraction of 2-propanol and the relative volatility of 2-propanol to water were analyzed. Results show that the azeotropic point of the system 2-propanol and water can be removed with addition of the salts, and the salting-out effects follow the order calcium nitrate > calcium chloride > magnesium nitrate > magnesium chloride. Furthermore, the LIQUAC model was adopted to correlate the VLE experimental data of the systems. The comparative results of the average relative deviation (Δz ̅) and the corresponding standard deviations (σ) between the experimental and calculated values indicate that LIQUAC model is suitable for the VLE calculation for the systems of 2-propanol + water + salts.

Imidazolium Chloride Ionic Liquid Mixtures as Separating Agents: Fuel Processing and Azeotrope Breaking

“…Overview of available experimental and predicted α ij (at 101.3 ± 2 kPa) for ethanol/water and 2-propanol/water mixtures in the presence of imidazolium chloride IL and calcium chloride. Open circles (○) and crosses (×) represent the experimental data available for CaCl 2 − and [C 4 mim]­Cl, − respectively, and the dotted lines depict the COSMO-RS predictions using the TZVP parameterization.…”