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The influence of the addition of CaCl2 to the water + propionic acid + 1-butanol ternary system was studied at (303.15 ± 0.05) K. The quaternary system was represented projecting four sectional quaternary planes corresponding to 4.3%, 9.3%, 15.1%, and 20.3% CaCl2 in aqueous solution onto the face of the tetrahedron containing the ternary system water + propionic acid + 1-butanol. Therefore, all compositions are given on a salt-free basis for the solubility curves and for tie-line data. The addition of salt always enhances significantly the distribution coefficients and selectivities, while the region of heterogeneity increases as compared to the no-salt condition. Band type curves were obtained for solubility curves above 4.3% CaCl2, and no salt precipitation was observed. The experimental results show that CaCl2 is not distributed in the same proportion between the phases at equilibrium and that 1-butanol appears to be a good solvent for extraction purposes. A comparison between the influence of CaCl2 and NaCl on this ternary system is also made using these experimental results with earlier data. A high value of the Sestchenow's constant was obtained by a linear regression method, which is an indication that a great salting-out effect is produced by the addition of CaCl2, which is more important than for NaCl.

Isothermal vapor-liquid equilibrium data were determined by using a modified Boubllk-Benson still for the n -pentane-dlchloromethane system at 298.15 K. This system shows an azeotropic point at x1 = 0.55 and at 82.0 kPa. A test of thermodynamic consistency was applied to the activity coefficients. The results obtained were correlated In terms of the liquid activity coefficients of Margules, van Laar, Wilson, and UN I FAC equations. The best agreement with experimental data was given by Wilson's equations.

Densities, refractive indices, viscosities, enthalpies, vapour–liquid equilibria, and surface tensions were determined for the n-pentane + dichloromethane system at 298.15 K. From the experimental results, excess molar volumes, excess viscosities, excess molar enthalpies, excess molar Gibbs free energies, and excess surface tensions were calculated. From these data, qualitative information could be obtained about the interaction between both chemical species.