Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

ABSTRACT

Isobaric vapor-liquid equilibria (VLE) at 101.3 kPa were measured for the binary systems x1 2,2,4-trimethylpentane + (1- x1) 1-butanol or dibutyl ether (DBE) with an isobaric ebullometer. Activity coefficients and excess Gibbs free energies were determined. The Fredenslund point-to-point test and the Wisniak point-to- point and area tests were carried out to determine the thermodynamic consistency of the data. Three local composition models were employed to correlate the experimental VLE data (NRTL, Wilson and UNIQUAC). A derivation of CDSAP model was also used to correlate the experimental values. The UNIFAC model was used to predict the VLE data for both binary systems. Density, speed of sound and refractive index of binary mixtures have been measured at 298.15 K and at 101.3 kPa. Excess molar volumes, isentropic compresibilities and deviations in isentropic compressibility have been calculated from these experimental data. The excess properties upon mixing were correlated by using the Redlich-Kister polynomial.