Device for producing dimethyl disulfide co-produced dimethyl trisulfide

Abstract

The invention discloses a method for producing dimethyl disulfide co-produced dimethyl trisulfide. The method mainly comprises the following steps: dissolving sulfur in a dimethyl disulfide solution to enter a first reactor, enabling sulfur and dimethyl disulfide to produce dimethyl trisulfide in the reactor, and enabling dimethyl trisulfide and unreacted dimethyl disulfide to enter a first rectifying tower to be separated, wherein a dimethyl disulfide product can be obtained on the tower top, dimethyl trisulfide at the tower bottom can serve as a product for sales and can also enter a secondreactor with methyl mercaptan to react so as to produce dimethyl disulfide; enabling a reaction solution to enter a first flash tank to remove hydrogen sulfide, enabling a liquid phase to enter the top of a second rectifying tower to separate hydrogen sulfide and methyl mercaptan, enabling the materials at the tower bottom to enter a third rectifying tower, extracting dimethyl disulfide on the topof the rectifying tower, enabling a tower bottom solution to circulate to enter the first rectifying tower, and separating again, thereby obtaining product dimethyl disulfide. With the adoption of the method for respectively refining and separating the reactive materials twice, the two products, namely dimethyl disulfide and dimethyl trisulfide, can be obtained. The method has the advantages of being reasonable in process flow configuration, low in equipment investment, excellent in reaction selectivity, low in impurity content in reaction products, simple in refining and separating process,high in product purity and easy to control.

Description

technical field [0001] The invention relates to the technical field of producing dimethyl disulfide and co-producing dimethyl trisulfide, in particular to a device for producing dimethyl disulfide and co-producing dimethyl trisulfide. Background technique [0002] Dimethyl disulfide DMDS is an intermediate of pesticides and dyes, and is the raw material for fenthion, methocarb, methocarb, fonsofos, methanesulfonic acid, and methanesulfonyl chloride, and is used as a catalyst passivation in the petroleum industry Agents, such as ethylene cracking furnace coking inhibitors, hydrodesulfurization and pre-vulcanization process activators; rubber liquid vulcanizing agents, curing agent DADMT raw materials and organic solvents. Dimethyl trisulfide is mainly used as a pharmaceutical intermediate, and a small amount is used as a food additive in gravy, soup and other food flavors. Both dimethyl disulfide and dimethyl trisulfide are fine chemical products that are in short supply and...

AI Technical Summary

Problems solved by technology

[0005] 1. The final reaction material enters a single rectification tower for refining and separation, so that the concentration of dimethyl trisulfide contained in the dimethyl disulfide solution circulating in the tower kettle is relatively high, and the solution enters the dimethyl trisulfide reactor to generate dimethyl trisulfide Tetrasulfide or polysulfide, resulting in low conversion rate of the target product and complicated refining and separation process

[0006] 2. The product of the reaction in the dimethyl trisulfide reactor is a mixture of dimethyl trisulfide and dimethyl disulfide, which does not contain hydrogen sulfide and methyl mercaptan. The mixture is not refined and separated before entering the secondary Methyl disulfide reactor, resulting in large investment in dimethyl disulfide reactor and refining and separation equipment, and increased catalyst consumption for the reaction

[0007] 3. During the process of returning the materials in the rectification tower to the reactor, the heavy components, metal ions, and salts accumulated in the system cannot be removed in time, which affects the purity and yield of dimethyl disulfide products

[0008] Among the currently published invention patents, there is no relevant report on the co-production of dimethyl trisulfide in the production of dimethyl disulfide

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