Phase equilibrium for capsaicin+water+ethanol+supercritical carbon dioxide

The possibility of extracting capsaicin with supercritical carbon dioxide from a hydroalcholic mixture containing the alkaloid was investigated. High-pressure phase equilibrium on the quaternary system CO2+ethanol+water+capsaicin was measured in order to obtain the separation factor of the natural product from hydro-alcoholic model mixtures. Experiments on phase equilibrium behavior were performed at several pressures (12, 15 and 18 MPa) and temperatures of 40 and 50 °C. The separation factors for three mixtures of different composition—0.40 water+0.60 ethanol mass fraction and 0.9 water+0.10 ethanol mass fraction, containing 0.02% of capsaicin and 0.40 water mass fraction containing 0.04% of capsaicin—are compared. The effect of the water content in the selectivity of the extraction process is discussed.