Abstract: A process for decaffeinating raw coffee by selective extraction of the caffeine by means of a solvent that is liquid under normal conditions. Raw coffee beans are extracted for between one and several hours by means of a liquid solvent that is comprised of water and that has been saturated with carbon dioxide or other suitable gas or gas mixture at a temperature of between about 20.degree. C. and 110.degree. C. and a pressure of between about 30 bar and 300 bar to provide a charged liquid solvent. The pressure is reduced abruptly or within a few minutes to a pressure between about 1 bar and 10 bar to expand the raw coffee beans. The expanded raw coffee beans are rinsed in the liquid solvent for a period of between a few minutes and two hours.

Abstract: A method and apparatus for the separation of viscous mixtures, comprising charging the mixture with solvent to form a dispersion before extraction to improve the extraction over a simple solvent extraction. The mixture to be treated is charged with solvent before the extraction and is then sprayed into the extraction column where it is dispersed. This treatment provides extraction of highly viscous, pasty materials. The charging with solvent can take place until the mixture is saturated with the solvent, and favorable temperature and pressure conditions for charging may be provided in a charging column that is separate from the extraction column.

Abstract: A simple, reliable process for decaffeinating green coffee beans to a high degree while avoiding denaturation of the green coffee beans includes wetting the green coffee beans to a high water content of 35-50%-wt.; compressing the beans in a pressure chamber for a period of a few minutes to several hours in an atmosphere comprised of a supercritical fluid which is a gas at STP, at a temperature ranging from 20.degree. to 80.degree. C. under a critical pressure ranging from 75 to 300 bar; decompressing the wetted beans from critical pressure p.sub.c to a pressure p for which p.sub.c p.gtoreq.p.gtoreq.1 bar abruptly or in the space of a few minutes, while avoiding freezing the green coffee beans; washing with water or with the supercritical fluid for selective extraction of the caffeine; repeating the process one or more times; centrifuging; drying; and roasting the beans. Further, caffeine is recovered in a known manner from the washing medium.

Abstract: A simple, reliable process for decaffeinating green coffee beans to a high degree while avoiding denaturation of the green coffee beans includes wetting the green coffee beans to a high water content of 35-50%-wt.; compressing the beans in a pressure chamber for a period of a few minutes to several hours in an atmosphere comprised of a supercritical fluid which is a gas at STP, at a temperature ranging from 20.degree. to 80.degree. C. under a critical pressure ranging from 75 to 300 bar; decompressing the wetted beans from critical pressure p.sub.c to a pressure p for which p.sub.c .ltoreq.p.ltoreq.1 bar abruptly or in the space of a few minutes, while avoiding freezing the green coffee beans; washing with water or with the supercritical fluid for selective extraction of the caffeine; repeating the process one or more times; centrifuging; drying; and roasting the beans. Further, caffeine is recovered in a known manner from the washing medium.

Abstract: A process for the continuous extraction of mixtures of organic substances including high boiling point constituents and/or constituents which do not boil but which melt with at least one solvent in the supercritical state, selected from the group consisting of CO.sub.2, propane, butane, pentane, petroleum ether, water, and having a critical temperature, T.sub.k, and a critical pressure, P.sub.