Phase equilibria in complex systems of palm oil deodorizer condensates and supercritical carbon dioxide: experiments and correlation

Abstract

Experimental phase equilibrium data were determined for supercritical carbon dioxide and complex mixtures of palm oil deodorizer condensates containing fatty acids and tocopherols. A static analytical apparatus was used, and samples from liquid and vapor phases were analyzed by gas chromatography (GC). The distribution coefficients of individual components or pseudocomponents could thus be determined. The data obtained were correlated with the Peng–Robinson and Redlich–Kwong–Aspen equations of state using van der Waals type and Wong–Sandler mixing rules. The predictive PSRK model was also used. Furthermore, literature data of the CO 2–oleic acid system was treated with these equations. The Redlich–Kwong–Aspen model performed best in the (pseudo-)binary systems, while the g E-model mixing rules were not successful. None of the models was able to correlate the pseudoternary system CO 2–fatty acids–tocopherols in a satisfactory manner.