Excess Gibbs Energy and Local Compositions in the Mixtures C2, C3 Alkane Diols and Triols with Water at Various Pressures

摘要

In this work the excess molar Gibbs energy of binary mixtures of water with ethylene glycol, 1,2-propanediol, 1,3-propanediol or glycerol was calculated at 298.15 K and pressures from 0.1 to 100 MPa. Thermodynamic data were used to calculate the Kirkwood-Buff integrals and the parameters of local composition (a dagger n (ij) ). The excess Gibbs energies and parameters of local compositions for aqueous mixtures of the alcohols with different number of hydroxyl groups and internal structures are compared. Similar character of intermolecular interactions has been established for all mixtures studied. It was discovered that external pressure causes an increase of local nonhomogeneity for all systems. The pressure influence was more pronounced for the aqueous mixtures of propanediols.