Vaporization/sublimation enthalpies of mono- and dimethyl-esters estimated by solution calorimetry method

Abstract

© 2020 Elsevier B.V. The additive scheme for calculating the solvation enthalpies of aliphatic compounds has been developed for linear mono- and dimethyl-esters. Ester group contribution to the enthalpy of solvation in n-heptane was obtained. Accuracy of the proposed approach for determination of solvation enthalpies of linear mono- and dimethyl-esters was tested by comparison with experimental solvation enthalpies. In most cases, deviations do not exceed 1 kJ·mol−1. It was found that the dependence of the solution enthalpies of mono- and dimethyl-esters on the number of carbon atoms in the molecule can be fitted by power function. This dependence and a group-additivity scheme for solvation enthalpy were used for estimation of the enthalpies of phase transitions of mono- and dimethyl-esters. Evaluated values of sublimation, vaporization, and fusion enthalpies at 298.15 K are in good agreement with experimental data obtained by conventional methods.