Models for predicting critical properties of multicomponent mixtures of supercritical fluids

Efforts by researchers to quantitatively characterize the phase behavior of supercritical fluids have yielded incomplete results. Modification of equations such as the van der Waals equation of state, the Berthelot equation, the Redlich-Kwong equation, and Clausius equation have been studied along with other pertinent empirical approximations and thermodynamic considerations to affectively model phase behavior of fluids in general and supercritical fluids in particular. Current methods of prediction of supercritical fluid mixtures generally rely upon approximations established by Peng and Robinson, Soave, and other researchers. Such predictive and theoretical methods are limited by phase equilibria conditions such as, prediction of solubility (including solvent clustering around the solute), accurate prediction of density in the critical region, and mixture diluteness and asymmetry. This particular paper concentrates on equation of state and empirical methods and analysis related to binary and multicomponent mixtures.