Improved means for extracting fixed and mineral oils from natural resources

摘要

A process for extracting fixed or mineral oil from a substance, such as ground nuts, cocoa butter, sunflower seeds or mud, comprises contacting the substance in a sealed first vessel 1 with 1,1,1,2-tetrafluoroethane (HFC 134a) and elevating the temperature of the vessel 1. The resulting solution is separated from the substance by transferring it to a second vessel 2, preferably through a filter 7, and the oil is released from the solution by cooling at least the second vessel 2. Finally, the oil is separated from the solution, preferably by decantation through valves 14, 13. A co-solvent, which is preferably liquid at room temperature, may be used and is most preferably chosen from lower alkanes, lower alcohols, acetone, dimethyl ether, diethyl ether or liquefied gases, such as butane. The vessel 1 may be heated to a temperature of 40 to 60 {C, preferably by a water or oil bath 6, and the second vessel 2 may be cooled to -10 to 25 {C, preferably by coils 9 which contain a flow of cooling liquid.