Heats of mixing of cyclohexane with 1-propanol and 2-propanol

Abstract

The concentration dependences of excess enthalpies of the binary systems cyclohexane-1-propanol and cyclohexane-2-propanol were measured in an isothermal calorimeter at six temperatures in the range of 25-50°C. For the quantitative description of the concentration and temperature dependences of heats of mixing, the Liebermann-Wilhelm model of associated solution was used extended by the assumption of polynomial temperature dependence of the interaction parameter. It follows from the comparison of chemical and physical contribution to the excess enthalpy that heats of mixing in the system with 1-propanol are given mostly by a specific interaction of hydrogen bond. The excess Gibbs energies were estimated using an interaction parameter calculated from heats of mixing. The values obtained are systematically higher and have rather semi-quantitative character.