摘要:
A process for the recovery of unsaturated fatty acids with at least 16 carbon atoms in the molecule or a derivative of such a fatty acid from a mixture of fatty acids and/or fatty acid derivatives by column chromatography with supercritical or liquid carbon dioxide as the mobile phase comprises using aluminum oxide, optionally pretreated with alkali, as the stationary phase. The pre-treatment of the aluminum oxide is conveniently effected by contacting the particulate aluminum oxide with an aqueous solution of an alkali metal or alkaline earth metal hydroxide, optionally supplemented with a water-miscible or water-soluble organic solvent, in the pH range of about 10 to about 13 over several hours. The unsaturated fatty acids or fatty acid derivatives produced chromatographically in this manner are suitable as valuable active agents in the fields of nutrition and medicine.
摘要:
A process for the extraction of oils from oil-containing solid vegetable material by means of compressed gases, wherein said vegetable material is extracted with a mixture consisting of a supercritical gas and a subcritical entraining agent selected from the group consisting of propane, butane, pentane, ethanol, ethyl acetate, formaldehydedimethylacetal, CHF.sub.2 Cl and mixtures thereof, wherein the conditions of pressure, temperature and composition are selected so as to form a single fluid phase in said mixture of oil, supercritical gas and subcritical entraining agent, said extraction resulting in a loaded extractant which is separated from the extracted material in a separator and converted into an oil-rich liquid phase and a gaseous oil-exhausted phase in a regenerator by temperature increase and/or pressure decrease and said oil-rich phase and said oil-exhausted phase are separated and the oil-rich phase is pressure relieved, whereupon, if desired, the entraining agent remaining in the obtained oil is recovered.
摘要:
The invention involves a process for the decaffeination of coffee, wherein--usually moistened--coffee is exposed to a circulating medium essentially composed of a compressed gas and an entrainer; this medium is subjected to partial condensation of the caffeine containing entrainer, in the absence of decompression; the caffeine is recovered from the condensate by evaporation of the entrainer portion thereof, and the medium is recycled to the coffee for continued extraction of caffeine therefrom.
摘要:
An arrangement for extracting crude oil from oil shale comprising: a low temperature carbonization reactor; a processing means for feeding a slurry of oil shale, solvent and hydrogen into the low temperature carbonization reactor; a separating means for separating the resulting gaseous low temperature carbonization mixture from the used oil shale and for separating the low temperature carbonization mixture into gaseous and liquid low temperature carbonization products; a gas turbine the exhaust gas outlet of which is connected to two heat exchangers, one of which heat exchangers is disposed in a circulation system for a scavenging gas, which circulation system includes a separating reactor (which forms part of said separating means) in which in use the scavenging gas flows upwardly in counterflow to the oil shale for separation of the fluid low temperature carbonization mixture from the used oil shale, and the other of which heat exchangers is disposed between the low temperature carbonization reactor and said separating reactor; the low temperature carbonization reactor including a fluidizing cooler with a fluidized bed means for feeding used oil shale from the separating reactor to the fluidized bed and means for feeding turbine exhaust gas from either or both of said two heat exchangers to the fluidized bed for fluidizing the bed.
摘要:
From palm oil, valuable compounds like the tocochromanols, carotenoids, phytosterols and other can be derived in the new process. Fractions derived from crude palm oil, already enriched to some extent in tocochromanols, carotenoids, phytosterols, and others, are treated by supercritical fluid technology in a unique combination of counter current separation with selective adsorption and desorption using supercritical fluids.
摘要:
A process and system for low-temperature carbonization of oil shale, oil sands and similar oil-bearing solids includes low-temperature carbonization of oil-bearing solids in a high-pressure fluidized bed reactor in the presence of a substance selected from the group consisting of hydrogen and steam at temperatures substantially between 400.degree.and 600.degree. C. for producing low-temperature carbonization gas. The low-temperature carbonization gas is condensed in at least two stages for producing relatively higher boiling and relatively lower boiling oil fractions. The oil-bearing solids are peripherally mashed with the higher boiling oil fraction of the low-temperature carbonization gas, before introducing the oil-bearing solids into the high-pressure fluidized bed reactor. The oil-bearing solids mashed with the higher boiling oil fraction are returned to the high-pressure fluidized bed reactor.
摘要:
A process is disclosed of separating fine solids from oil in which the solids are dispersed which comprising contacting said oil with a combination of a compressed above-critical gas and an entraining agent at such temperature and such pressure that the system consisting of the oil, entraining agent and above-critical gas constitutes a single phase, withdrawing and separating the so-withdrawn phase into a liquid phase rich in oil and a gas phase lean in oil, the single-phase mixture of oil, entraining agent and above-critical gas from the solids.
摘要:
A process for extracting hydrocarbons from oil shale comprising the steps of subjecting oil shale under superatmospheric pressure in the presence of hydrogen and steam, to low temperature hydrogenating distillation; separating the resulting fluid distillation mixture into liquid and gaseous products; and returning water and hydrogen separated from the fluid distillation mixture to the low temperature distillation; in which:heat is drawn-off from the hot oil shale, after treatment in a low temperature hydrogenating distillation reactor, by the shale being sprayed wtih water whereby saturated steam is produced in decreasing pressure stages;the saturated steam of the pressure stages and water extracted during product separation are fed into the individual stages of a multi-stage compressor driven by a gas turbine, and are then delivered via a steam supply line to the reactor;the gas turbine is fuelled by supplying separated-off gaseous distillation products thereto; andthe exhaust gases of the gas turbine are fed to a heat exchanger arranged in the steam supply line.
摘要:
The invention involves a process for substantially separating the components of mixtures of substances at least one of which is of low volatility while the other is of low or no volatility, the process using a compressed gas under supercritical conditions and an entrainer which increases the concentration of said mixture in the gaseous phase as well as the separation factor between the components to be separated. The process operates in two distillation zones the first of which substantially separates the components of low volatility in a process similar to a rectification process while the second distillation zone separates the top product of the first distillation zone from the gas with the aid of the entrainer which is condensed partially and in this state is passed in countercurrent to the gas carrying the separated component of low volatility.
摘要:
From palm oil valuable compounds like the tocochromanols, carotenoids, phytosterols, and others can be derived. Enrichment to highly concentrated fractions is hindered by the enormous number of components involved, the very low volatility, the very low solubility of many of the compounds in organic solvents, and the high viscosity of the mixtures to be processed. Starting materials for the new process are enriched fractions of tocochromanols (about 20 to about 50 wt.-%) and/or carotenoids (about 10 to 30 wt.-%) from palm oil obtained by conventional processes, or by counter current multistage processes with supercritical carbon dioxide. These processes, not addressed here, may comprise: Removal of free fatty acids, transesterification of the triglycerides to methyl or ethyl esters, removal of the esters, e.g. by short path distillation, separation of the tocochromanol fraction from the carotenoid fraction by cooling. In the new process, fractions derived from crude palm oil, already enriched to some extent in tocochromanols, carotenoids, phytosterols, and others, are being treated by supercritical fluid technology in a unique combination of counter current separation with selective adsorption and desorption using supercritical fluids. A first enrichment, comprising one or more separation steps by application of a near critical or a supercritical fluid in a single or multistage (counter current) separation process is combined appropriately with a second enrichment step wherein the product of the first enrichment step is directly adsorbed on an adsorbent (silicagel) by passing the product flow over a fixed bed of adsorbent without substantial pressure change, and subsequent desorption with the same (or an other) near critical or supercritical fluid at the same or a different pressure as in the first separation, or by a pre-designed sequence of pressures and temperatures. For the tocochromanol enrichment, carbon dioxide at near critical conditions above the critical temperature of carbon dioxide is used. For the carotenoid enrichment, propane at near critical conditions below the critical temperature of propane is used.