Fractionation of edible oil model mixtures by supercritical carbon dioxidein a packed column. Part I: Experimental results

The design of countercurrent packed columns operating under high-pressure c onditions requires knowledge of their hydrodynamic and mass transfer behavi or. A laboratory-scale continuous supercritical fluid extraction apparatus was developed with the purpose of obtaining data needed for such designs. T he current work is part of a study to assess the feasibility of supercritic al carbon dioxide in fractionating a mixture of squalene and methyl oleate. This mixture partly emulates the residues obtained from the olive oil refi ning process. Phase equilibrium data were previously measured to evaluate t he best operating conditions. Here, we examine the continuous fractionation of two different feeds, with 40 and 70 wt % of squalene, under various ext raction conditions. An extraction yield as high as 90 wt % of squalene in t he raffinate phase was achieved. The selectivity and extraction efficiency were determined as functions of the oil-to-carbon dioxide flow ratio as wel l as the reflux ratio. In a subsequent paper (Part II), the measured hold-u p and mass transfer coefficients will be compared with mass transfer correl ations from the literature, and a model will be developed.