Simple fractionation through the supercritical carbon dioxide extraction of palm kernel oil

Supercritical carbon dioxide (SC-CO2) in the pressure range 20.7-48.3 MPa (3000-7000 psi) and temperatures between 40 and 80 degrees C was used as a solvent in the extraction of palm kernel oil (PKO). At 20.7 and 27.6 MPa, the solubility of PKO in SC-CO2 decreased with temperature. However, at higher pressures of 34.5, 41.4 and 48.3 MPa, the solubility increased with temperature. The composition of the oil extracted varied with time. Earlier fractions were rich in short-chain triglicerides, while the later fractions were rich in longer chain triglicerides and unsaturated triglicerides. However, at higher pressures, the fractionation effect diminished and the oil could be considered as a single component. At 48.3 MPa and 80 degrees C, the solubility of PKO in SC-CO2 of about 20% was relatively high compared with that of soybean oil of about 3%. (C) 2000 Elsevier Science B.V. All rights reserved.