Liquid phase PVTx properties of binary mixtures of (water + ethylene glycol) in the range from 278.15 to 323.15 K and from 0.1 to 100 MPa. II. Molar isothermal compressions, molar isobaric expansions, thermal pressure coefficients and internal pressure

Abstract

Molar isothermal compressions, molar isobaric expansions, molar coefficients of thermal pressure, and internal pressures of {water (1)+ethylene glycol (2)} mixture over the whole concentration range, as well as partial molar isothermal compressions and partial isobaric expansions of water in ethylene glycol and of ethylene glycol in water at infinite dilution were calculated at pressures from 0.1 to 100MPa and at temperatures from 278.15 to 323.15K. It was revealed that concentration dependences of molar isothermal compressions KT,m, molar isobaric expansions EP,m, and thermal pressure coefficients, β, on ethylene glycol molar fraction had extremes. Temperature and baric dependences of internal pressure of the mixture were almost linear, and coefficients of these dependences at low ethylene glycol concentrations differed from those coefficients for water, ethylene glycol, and their mixtures with high diol content. Analysis of the volume characteristics obtained confirmed both hydrophilic and hydrophobic ethylene glycol nature.