Refining method of methyl chloroformate

Abstract

The invention discloses a refining method of methyl chloroformate. The refining method specifically comprises the following steps: introducing CO and chlorine into a phosgene generator according to the molar ratio of 1 to 1.05 and generating synthetic reaction through the phosgene generator under the catalytic action of coconut shell activated carbon to generate phosgene; introducing the phosgene and methanol into an esterification tower for esterification reaction, acyl chlorohydrolysis and gas-liquid bubbling reaction according to the molar ratio of 1 to 1.1 to synthesize the methyl chloroformate; after the completion of esterification, overflowing and transferring a methanol and methyl chloroformate reaction liquid phase from the top of a reactor, into a methyl ester kettle, performing gas expulsion after collection and refining; moving out heat released by the reaction from a shell-side refrigerant to ensure that the reaction is performed at a temperature of below 35 DEG C; pumping tail gas at the top of the reactor to a tail-breaking damage area for continuous treatment of light-containing tail gas after effective components cooled and recovered by two-stage ice water enter ice cold and low temperature methanol falling film absorption in a centralized manner. The refining method disclosed by the invention has the benefits that after the reaction of the methyl chloroformate, toxic gas containing hydrogen chloride can be treated, useful substances are effectively recovered, the synthetic cost is reduced, and the economic benefits are improved.

Description

technical field [0001] The invention relates to the technical field of pesticide synthesis, in particular to a method for refining methyl chloroformate. Background technique [0002] Methyl chloroformate is an organic compound, highly toxic, flammable, and corrosive; a colorless liquid with a strong pungent odor; molecular weight: 94.50; vapor pressure: 16.93kPa / 20°C; flash point: 18~23°C; boiling point : 71.4°C; insoluble in water, soluble in most organic solvents such as benzene, methanol, ether; relative density (water = 1) 1.22; relative density (air = 1) 3.26; stable; slightly soluble in water and gradually decomposed by water; It has a lachrymatory effect, and its vapor strongly irritates the eyes and respiratory tract, and can also be absorbed through the skin to cause poisoning. [0003] Industrially, it is obtained by esterification of methanol and phosgene; in batch production, phosgene is passed into methanol and stirred and reacted in a glass-lined reaction pot....

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Problems solved by technology

[0004] At the same time, because the output of the existing equipment is relatively high, and its molecular structure contains various functional groups such as methyl, methoxy, carbonyl, and acid chloride, it has good reactivity and can be used for carbonylation, methylation, and methoxylation. , carbonyl methoxylation and transesterification and other organic synthesis reactions. The existing technology produces methyl chloroformate. Because the reaction time of the reactants is long, there are too many by-products, which will lead to the conversion rate of the material. lower

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