The phase behavior of crude palm oil (CPO) with supercritical CO 2 was successfully modeled in an Aspen Plus ® 10.2.1 commercial simulator (Aspen Technology Inc., Cambridge, MA) using the Redlich-Kwong-Aspen (RKA) equation of state thermodynamic model. The modeling procedure involved estimating pure component vapor pressures and critical properties and computing a regression of phase equilibrium behavior. The interaction parameters for the RKA model were obtained from the regression of experimental phase equilibrium data for a binary system of palm oil components-supercritical CO 2 available in the literature. The distribution coefficients and solubilities of palm oil components obtained from this simulation showed good agreement with experimental data obtained from the literature. The model provides an efficient and cost-effective alternative for the preliminary design and optimization of a supercritical fluid extraction process involving a complex CPO-supercritical CO 2 system.Over the years, supercritical fluid extraction (SFE) technology has developed rapidly and found applications in the commercial production of vegetable oils, including palm oil. Palm oil contains various components such as MG (<1%), DG (2-7%), TG (>90%), FFA (3-5%), phospholipids, pigmented compounds, and several nutritionally bioactive compounds (1). Minor components such as β-carotene and tocopherol are often degraded or lost during the bleaching and refining processes, which require high operating temperatures of up to 240°C. Selective supercritical CO 2 extraction of these highvalue but thermally unstable components from crude palm oil (CPO) has enabled operation at mild temperatures of less than 100°C. In addition, the inert solvent used can be easily separated and recovered, thereby leading to a pollution-free operation. All these advantages combine to make SFE of components in palm oil a desirable alternative to conventional processing methods such as chemical and physical refining.By correlating limited experimental data gained from literature using thermodynamic models, a general representation of the phase behavior of a system can be determined, thus making it possible to reduce experimental work. The equation of state has been shown to adequately represent the phase behavior of lipid-related components with supercritical CO 2 (2-5). It is anticipated that the equation of state also can model the phase equilibrium of a palm oil components-supercritical CO 2 system. However, a reliable phase equilibrium model is required in the analysis of the SFE process involving a palm oil-supercritical CO 2 system since the system comprises a highly dissimilar mixture of high M.W. TG and low M.W. supercritical CO 2 . In addition, such a model must be applicable over a wide range of temperatures and pressures to yield some accurate quantitative values of the mutual solubilities, compositions of coexisting phases, and distribution coefficients that are of fundamental importance in the design of a countercurrent SFE process. The steps involved in...

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