Vapor Pressures and Thermophysical Properties of Ethylene Carbonate, Propylene Carbonate, γ-Valerolactone, and γ-Butyrolactone

In this work, a thermodynamic study of four important industrial solvents, ethylene carbonate (CAS RN: 96-49-1), propylene carbonate (CAS RN: 108-32-7), gamma-valerolactone (CAS RN: 108-29-2), and gamma-butyrolactone (CAS RN: 96-48-0), is presented. The vapor pressure measurements were performed by static method using two apparatuses in a combined temperature interval (238-363) K. Heat capacities of condensed phases were measured by Tian-Calvet calorimetry in the temperature interval (262-358) K. The phase behavior of ethylene carbonate and gamma-valerolactone was investigated by a heat-flux DSC from 183-303 and 328 K, respectively. Ideal-gas thermodynamic properties were calculated using the methods of statistical thermodynamics based on calculated fundamental vibrational frequencies and molecular structure data. A consistent thermodynamic description of all involved properties (calculated ideal-gas heat capacities and experimental data on vapor pressures, condensed phase heat capacities, and vaporization enthalpies) was achieved by their simultaneous correlation.