The perturbed hard chain theory for the prediction of supercritical fluid extraction: pure component properties

Abstract

A perturbed hard chain theory based equation of state is investigated in view of its application to supercritical fluid extraction process calculations. The investigation is focused on pure component properties, since it is essential for any equation to give a good description of volumetric and equilibrium properties of pure compounds before extending it to mixtures. The equation gives good results as far as the correlation of polar and non-polar fluids is concerned. Generalized correlations of the equation parameters are established in terms of Bondi's volume. Their applicability is evaluated on components not included in the data base for the parameter estimation. The results obtained are fairly good, showing that the generalized correlations are convenient specifically for those compounds for which experimental data are difficult to measure. A procedure is proposed to reduce the equation to a one-parameter equation without losing accurary. The single parameter is calculated from vapor pressure datum.