The aim of this work is experimental determination of density, ρ, refractive index, n D, viscosity, η, and their derivatives for four binary systems containing glycerol in the mixture with butanol isomers: 1-butanol, 2-butanol, isobutanol, and tert-butanol. Experimental results were carried out for all concentration ranges at atmospheric pressure and at a temperature interval of 293.15–318.15 K except for the mixtures with tert-butanol because of high melting temperatures, so the measurements were made from 303 K. Results of experimental measurements were further used to estimate, for each investigated mixture, excess molar volumes, partial molar volumes, apparent molar volumes, thermal isobaric expansibilities, excess thermal expansibilities and partial molar volumes at infinite dilution, the viscosity deviations, and the excess energies of activation. In addition to that, the infrared spectra of all the systems have been recorded at three concentrations at room temperature. The excess molar volumes V E and excess thermal expansitivities for all investigated systems are found negative over the whole composition range and at all temperatures studied, and deviations from ideality increase with increasing temperature. Negative values of viscosity deviation appear for all systems, but contrary to the excess molar volumes, the deviations from ideality decrease with temperature rising. The excess molar calculated properties were well fitted using the empirical Redlich–Kister polynomial. All the properties measured and calculated in this work have shown a significant influence of the structure of the molecules including the size, shape, and the position of the hydroxyl groups of the components. As expected, the infrared spectra of these binary mixtures prepared with these four butanol isomers show strong hydrogen bonding capability.

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Isothermal vapor−liquid equilibria (VLE) are measured for three binary systems containing cyclic ethers: 1,3-dioxolane, 1,4-dioxane, or tetrahydropyran in mixture with 1,2-dichloroethane at 10 temperatures ranging from 273.15 to 353.15 K. A laboratory apparatus using the static method was employed to carry out the vapor pressures of the pure components and the mixtures. The VLE data were reduced by the Redlich−Kister equation and used to calculate activity coefficients then excess molar Gibbs free energies G E . The nonideality of the vapor pressure was considered in terms of the second molar virial coefficient. Both the mixtures formed by tetrahydropyran or 1,3-dioxolane with 1,2-dichloroethane show a minimum boiling point azeotrope. The experimental data were compared with the results provided for the modified UNIFAC (Do) and the DISQUAC models.