Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

ABSTRACT

Isobaric vapor-liquid equilibrium (VLE) data for the binary systems of toluene + o-xylene, benzene + o-xylene, nonane + benzene and nonane + heptane were measured at 101.3 kPa by using a modified Othmer still. The thermodynamic consistency of these new VLE data was checked by using the point to point test of Van Ness. No azeotrope was found in these binary systems investigated. While nonane + benzenewere found to have large positive deviation, toluene + o-xylene, benzene + o-xylene, and nonane + heptane exhibited large negative deviation from ideal behavior. The binary interaction parameters of the Wilson,the NRTL, the UNIQUAC models and the SRK equation of state for these four binary systems were determined through the VLE data reduction. These new VLE data were compared with the predicted valuesfrom the UNIFAC and the COSMO-RS (conductor-like screening model for realistic solvents) models as well. Generally, reasonable agreement was found between the predicted results and the experimentalvalues, except for nonane + benzene system.