Isothermal vapour–liquid equilibria and excess molar enthalpies of hex-2-yne + methyl butyl ether and hex-3-yne + dibutyl ether mixtures

The vapour pressures of liquid hex-2-yne + methyl butyl ether (MBE) and hex-3-yne + dibutyl ether (DBE) binary mixtures and of the four pure components are measured by a static method in the temperature range from 263 to 354 K. The isoplethal T–P data are reported and correlated with the Antoine equation. Interpolated data are also reported. Excess molar Gibbs energies, GE, are calculated for several constant temperatures, taking into account the vapour-phase imperfection in terms of the second virial coefficients, and were fitted to the Redlich–Kister equation. Calorimetric excess enthalpy, HE, measurements for these binary mixtures are also reported at 298.15 K. The experimental VLE and HE data were used, examining the binary mixtures hex-2-yne + MBE and hex-3-yne + DBE in the framework of the DISQUAC and modified UNIFAC (Do) models.