29 research outputs found

    An Efficient Way of Visualization of Mutual Solubility Data in the Whole Range of Compositions

    No full text
    An efficient way or stretching phase diagrams is proposed that represents the whole composition range and reveals details of low-solubility regions. It is based on the transformation of mole fraction <i>x</i><sub>1</sub> to log<sub>10</sub>(<i>x</i><sub>1</sub>/<i>x</i><sub>2</sub>) = log<sub>10</sub>(<i>x</i><sub>1</sub>/(1 – <i>x</i><sub>1</sub>)) for binary mixtures. While the primary application is liquid–liquid and solid–liquid equilibria, the use of this method for other properties may also be beneficial. An extension on ternary mixtures is also discussed

    Reparameterization of COSMO-SAC for Phase Equilibrium Properties Based on Critically Evaluated Data

    No full text
    COSMO-SAC model was reparameterized with use of the critically evaluated data generated by the NIST ThermoData Engine for vapor–liquid equilibria, excess enthalpies for binary mixtures, and activity coefficients of binary mixture components. The calculated σ-profile library contained 897 individual compounds. The temperature-dependent σ profiles included contributions of up to 40 conformers of a molecule. Splitting of the H-bonding σ profiles into OH and non-OH parts decreased the root-mean square deviation from the experimental data points by about 10% compared to the model using one H-bonding parameter. The original UNIFAC model demonstrated comparable performance with the more advanced COSMO-SAC variation. The challenges of uncertainty evaluation for parameters of the model and the predicted values are discussed
    corecore