Abstract
Separation of tocopherols from soybean sludge by supercritical carbon dioxide (SC-CO2) and nitrous oxide (SC-N2O) was carried out. This separation was not possible by supercritical fluid (SCF) alone and consequently, it was considered necessary to esterify the sludge with ethanol. Greater separation was possible using sludge esterified free fatty acid with ethanol. Tocopherols could be concentrated by more than 64 %. The tocopherolscould be recovered by 90 % in this fraction by SC-CO2 extraction in conjunction with a silicic acid column and simple pretreatment. The silicic acid column could be regenerated for the most part by extraction with an entrainer, such as ethanol.
