Supercritical fluid has the special ability to dissolve other substances, first published in 1822 the French doctor Cagniard substance of critical phenomenon, and in 1879 was Hannay and Hogarth two scholars study found that inorganic salts can quickly dissolves in the supercritical ethanol, after decompression can immediately crystallization precipitation again. But because of the technology, equipment and so on, until the 1930 s, PilatGadlewicz two scientists just had the idea of "macromolecular compounds were extracted with liquefied gas. In the 1950 s, the United States, Countries such as the su to supercritical propane remove the tar in the heavy oil and metals, such as nickel, vanadium, etc., in the process of the lower segment chain solution after the deactivation of catalyst poisoning, but due to cost considerations, not all practical. 1954 Zosol confirmed with experimental method in supercritical carbon dioxide extraction can extract oil grease. Since then, the method of using supercritical fluid separation silent for a period of time, late in the 70 s, Germany's Stahl and others first made a breakthrough in experiment device of high pressure research, "supercritical carbon dioxide extraction" this new extraction, The research and application of separation technology will make substantial progress. In 1973 and 1978 after the first and the second energy crisis, supercritical carbon dioxide special dissolving ability, again brought to the attention of the industry. 1978 years later, Europe established in supercritical carbon dioxide extraction purification technology as extraction agent, to deal with a food factory of the ten million tons of products, such as supercritical carbon dioxide removal of caffeine in coffee beans, and the bitter taste of the beer in extract can spend on aroma components. Supercritical fluid extraction (sfe) technology for nearly 30 years aroused people's great interest, This new chemical technology has been widely and deeply studied in the field of chemical reaction and separation and purification, and has made great progress in the fields of medicine, chemical engineering, food and environmental protection

Carbon dioxide extraction