Isothermal Vapor–Liquid Equilibria and Excess Gibbs Energies for Binary Mixtures of Cyclic Ethers with 1,2-Dichloroethane

Abstract

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 GE. 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.