A kind of product refining method of epichlorohydrin prepared by propylene chloride epoxidation method

Abstract

The invention provides a product refining method for preparing epichlorohydrin by epoxidation of propylene chloride. The extraction phase of the reaction distillate of ECH prepared by epoxidation of propylene chloride is transported to T201, and after rectification, the gas at the top of the tower is condensed After the oil phase is partly refluxed back to the tower, part of the recovery is sent to the reaction unit for reuse; T201 tower bottom material enters T202 rectification; T202 tower top gas is condensed and partly refluxes back to the tower, and part of the recovery goes to the ECH recovery tower; T202 tower bottom material enters T203 rectification Distillation; T203 tower top gas is condensed and partly refluxed back to the tower, and part of it is taken out of the device as ECH products; T203 tower bottom materials enter T204 rectification; After cooling, it is sent to the high boiler storage tank; the top material of T202 is rectified by T205, and part of the top gas is condensed and returned to the tower, and part of it is extracted to T206 rectification; the material at the bottom of T205 is returned to T202; the gas at the top of T206 is partially refluxed after condensation Return to the tower, and part of it is recovered and reused in the reaction unit; the bottom material of the T-206 tower is sent to the low boiler storage tank after being cooled.

Description

technical field [0001] The invention belongs to the technical field of separation and purification of chemical substances, and in particular relates to the product purification of epichlorohydrin prepared by oxidizing allyl chloride and hydrogen peroxide and a method for separating 1-chloropropane from allyl chloride. Background technique [0002] Epichlorohydrin (ECH), also known as epichlorohydrin, is an important organic chemical raw material and fine chemical product, mainly used in the synthesis of glycerin, epoxy resin, epichlorohydrin rubber, nitroglycerin explosives, etc., and can also be used as fiber It is a solvent for plain esters, resins and cellulose ethers; it is also the main raw material for the production of surfactants, plasticizers, stabilizers, adhesives and ion exchange resins. The epoxy resin prepared from it has the characteristics of strong adhesion, resistance to chemical medium corrosion, low shrinkage, good chemical stability, high impact strength...

AI Technical Summary

Problems solved by technology

[0006] However, since 3-chloropropene contains a small amount of 1-chloropropane in the reaction raw material, it does not participate in the reaction, and its boiling point is close to that of 3-chloropropene, so it is difficult to separate the two

In the recovery process of excess chloropropene after the reaction, it will continue to accumulate and increase, resulting in a decrease in the quality of circulating 3-chloropropene, which in turn affects the quality of crude epichlorohydrin rectification and product epichlorohydrin

This is a key problem in the production of epichlorohydrin by hydrogen peroxide oxidation, and has seriously affected the deepening, popularization and application of the technology.

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