Abstract
The extraction of oilseed with supercritical CO2 was tested on the laboratory scale for the case of rapeseed. The influence of different rapeseed pre-treatments upon extraction time and solvent requirement was examined. The best results were obtained with flaked rapeseed press cake. Extraction at a pressure of 75 MPa appears to be more favourable than at 30 MPa, since extraction times are shorter and less water is co-extracted with oil.
The energy consumption for processes with sub- or supercritical separation and pressurisation by pump or compressor was calculated. It is energetically desirable to separate the dissolved seed oil from the compressed gas at such supercritical temperature and pressure conditions that the seed oil is almost insoluble. For oilseeds, a continuous high-pressure extraction process should be employed instead of the batch process used at present for other solid natural materials.
