Vapor-liquid phase equilibria of nonideal fluids with a G(E)-EoS model

This study dealt with the prediction and correlation of vapor-liquid equilibria behavior of nonideal fluids. The thermodynamic formalism of the G{dollar}rmsp{lcub}E{rcub}{dollar}-EoS models, which combines the two traditional methods {dollar}rmgamma{lcub}-{rcub}phi and phi{lcub}-{rcub}phi{dollar} used so far for low and high pressure phase equilibria correlations respectively, has been combined with the 1FG{dollar}rmsp{lcub}E{rcub}{dollar} model, based on one-fluid theory, to produce a more consistent approach to the phase equilibrium problem.; In the first part of our study we examine the predictive abilities of our model for vapor-liquid equilibria of highly nonideal fluids. The results establish the fact that the Huron-Vidal mixing rule with a one parameter version of the 1FG{dollar}rmsp{lcub}E{rcub}{dollar} model, is able to successfully utilize available experimental information at low pressures for phase equilibria predictions of multicomponent mixtures over an extended range of pressures and temperatures.; In the second part of the study we perform an analysis of the correlative abilities of the 1FG{dollar}rmsp{lcub}E{rcub}{dollar} model, as applied to hydrogen-hydrocarbon mixtures. The results of this part suggest that the unique local composition character of the 1FG{dollar}rmsp{lcub}E{rcub}{dollar} model, along with its one size and one temperature-dependent energy parameter, make it able to adequately describe vapor-liquid equilibria behavior of multicomponent mixtures for this highly asymmetric class of mixtures. Moreover, it is shown that the model parameters for binary hydrogen-hydrocarbon mixtures can be correlated to the acentric factor of the hydrocarbon.; The important class of the refrigerant mixtures was modeled in the third part of this study. The 1FG{dollar}rmsp{lcub}E{rcub}{dollar} model was introduced into the Wong-Sandler mixing rule, based on the infinite pressure state thermodynamic formalism. The results for these systems showed that a limited amount of experimental data, either at low or high pressures can be utilized to provide a parameter which is practically independent of the temperature set used. As shown from the results, this single parameter can be used to extend vapor-liquid equilibria predictions over a range of conditions for this difficult class of systems. More importantly, we set a heuristic rule able to screen multiparameter and one parameter models. A coordination temperature-parameter planet can be used as a predictive tool from a limited amount of information.; Our model comes in lieu of the G{dollar}rmsp{lcub}E{rcub}{dollar} models based on two-fluid theory, which are inconsistent with the one fluid character of an EoS. The 1FG{dollar}rmsp{lcub}E{rcub}{dollar}-EoS framework proposed in this work meets current needs in the area of Applied Thermodynamics, which require that the model's parameters can be obtained from a limited information of experimental data and can give for accurate phase equilibria predictions of nonideal mixtures from low to high pressures.