Method and device for producing sodium thiomethoxide from by-product obtained through synthesis of dimethyl sulfide

Abstract

The invention discloses a method and a device for producing sodium thiomethoxide from a by-product obtained through synthesis of dimethyl sulfide. Specifically, the by-product in a synthesis process of dimethyl sulfide is taken as a raw material, feed gas is pumped into a water extraction column, soft water is fed into the water extraction column from the upper part of the water extraction column, and methanol in the feed gas is extracted with the soft water; the material with methanol removed is subjected to distillation, and removed thioether returns to a dimethyl sulfide workshop for use; crude methyl mercaptan after thioether is removed is fed into a stripper, and most hydrogen sulfide in the raw material is removed through stripping; trace hydrogen sulfide is removed with an iron oxide desulfurizer, and refined methyl mercaptan gas is obtained; refined methyl mercaptan gas is fed into an absorption column and absorbed by liquid caustic soda, and a sodium thiomethoxide solution is obtained. The invention further provides the device corresponding to the method. The method can effectively produce a sodium thiomethoxide product from the by-product methyl mercaptan obtained through synthesis of dimethyl sulfide, waste is changed into wealth, and higher economic and environmental protection values are realized.

Description

technical field [0001] The invention belongs to the technical field of organic chemical industry, and in particular relates to a method for producing sodium methyl mercaptide solution by using methyl mercaptan, especially the by-produced methyl mercaptan in the synthesis process of dimethyl sulfide, as a raw material. Background technique [0002] Sodium methyl mercaptide is a colorless and transparent strong alkaline liquid with a special odor, which can be used as raw material for pesticides, medicines, and pigment intermediates, such as pesticide sigrazin, methomyl, and organic intermediate raw materials; food additives Raw materials for methionine, vitamin U, and rubber vulcanizing agents; antidotes for hydrogen sulfide poisoning; odorants for gas and natural gas, etc. [0003] At present, most domestic sodium methyl mercaptide products use sodium hydrosulfide as a raw material, react with dimethyl sulfate or methyl chloride to generate methyl mercaptan, and then absorb ...

AI Technical Summary

Problems solved by technology

Among them, dimethyl sulfate is a highly toxic raw material, and there are great safety hazards in the process of use, storage and transportation

The final yield of sodium methyl mercaptide in the dimethyl sulfate-sodium hydrosulfide process is only about 75% to 80%, and a large amount of waste water containing organic matter is produced during the production process, which has a great impact on the environment

Chloromethane-sodium hydrosulfide process produces sulfide and a large amount of waste water containing sodium chloride and organic matter, and subsequent treatment is relatively difficult

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