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Application and Characteristics of Supercritical Extraction Equipment

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Supercritical extraction equipment is an extraction and separation technology developed in the 1970s. Supercritical fluid has the characteristics of both gas and liquid. Its density is close to that of a liquid, and its viscosity and diffusion coefficient are close to that of a gas. It not only has the same solubility as liquid solvents, but also has excellent mass transfer performance.

Supercritical extraction equipment is an extraction and separation technology developed in the 20s of the 70th century. Supercritical fluids have both gaseous and liquid properties. Its density is close to liquid, and its viscosity and diffusion coefficient are close to gas. It not only has the same solubility as liquid solvents, but also has excellent mass transfer properties.

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At present, supercritical extraction equipment is widely used in CO2, which has a critical temperature of 31. 265. The critical pressure is 7. 18MPa, critical conditions are easy to reach. In the supercritical state, the density of CO2 fluids is very sensitive to changes in temperature and pressure, and its solubility is proportional to pressure within a certain range. Therefore, the solubility of the extract can be changed by changing the temperature and pressure of the system, so that it can be separated and extracted. Since SFE-CO2 is an environmentally friendly "green" chemical technique, it has become an effective medicinal plant.

Supercritical extraction equipment technology was first applied to large-scale industrial removal of plant factors from coffee beans, and later also applied to extract plant factors from tea. The plant factor content in coffee is 0.6%-3%, while the plant factor content in tea is about 1%-5%, and the extracted coffee can be used as a medicinal compress, while coffee without plant factors can meet people's needs. The traditional method adopts solvent extraction technology, which has problems such as solvent residue and low extraction rate. The application of supercritical carbon dioxide fluid extraction technology solves these problems, the purity of the product is greatly improved, and the carbon dioxide is easily soluble.

The supercritical extraction equipment is safe and non-toxic, and more importantly, the reaction conditions are mild. The requirements for equipment are not particularly high. Mass production is possible. The extraction process of coffee beans is as follows: the coffee beans are washed, poured into the extraction kettle, and then introduced into the special grade.

Supercritical extraction equipment is used for extraction. After the extract passes through the separation device, the plant factors are eluted by water and the carbon dioxide continues to circulate. Sometimes activated charcoal is used instead of water to elute plant factors. With the development of technology, the process of extracting plant factors has been greatly improved. Among the more successful is General Foods' Sol Norman Katz semi-continuous production method. The peculiarity of this method is that when feeding and discharging regularly, the material will be convectioned with the solvent in the equipment. In this way, the concentration of plant factors in the carbon dioxide fluid will be greatly increased, and the extracted non-plant factors will return to the substance, so the extracted coffee flavor is still pure.

Supercritical extraction equipment technology is widely used in the extraction of hops in the wine industry. The isoxanone contained in hops gives beer its unique aroma and freshness. In the past, when brewing directly with hops, the utilization rate of iso-acids was only close to 25%. Now, hop extracts are mostly used for brewing. The traditional extraction method is extraction with organic solvents. The yield is low and there is still solvent residue. After supercritical fluid extraction, the extraction rate is very high, -acid reaches 98.9%. The process of supercritical carbon dioxide fluid extraction of hops is as follows: first grind the hops into powder, then put them into the extraction kettle, introduce carbon dioxide fluid, and finally separate the products. This product is yellow-green paste with aromatic odor.

 

NANTONG WISDOM SCFE

The Company has committed to the field of supercritical fluid extraction equipment for 30 years.