Production method of dimethyl phosphite

Abstract

The invention relates to a production method of dimethyl phosphate, which takes phosphorus trichloride and methyl alcohol as raw materials for reaction. The method comprises the steps of: in a reaction chamber space having cross injection angle and the injection structures of the raw materials, respectively and continuously injecting and sending the phosphorus trichloride and the methyl alcohol which are based on the molar ratio of 1: (3.0-3.1) into the reaction chamber space through respective injection structures by corresponding pumping mechanisms for mixing together and reaction; then, introducing reaction material into a centrifugal cyclone separator with the pressure lower than that of the reaction chamber space along the tangential direction, and leading noncondensable gas and condensing liquid product to have centrifugal cyclone separation; and collecting the liquid dimethyl phosphate product descending along the inner wall of the centrifugal cyclone separator. The method can rapidly complete the reaction and the separation for products, effectively reduces the contact between HCl and the dimethyl phosphate, inhibits the occurrence of side reaction, improves the yield and the quality of the product, and greatly reduces the energy consumption.

Description

technical field [0001] What the present invention relates to is a kind of production method of improved dimethyl phosphite. Background technique [0002] Dimethyl phosphite is an important product in fine chemical industry. It is not only an intermediate for the production of glyphosate, trichlorfon, rice blast, omethoate and other pesticides, but also a raw material for organophosphorus corrosion inhibitors, dye additives, plastic additives and flame retardants, and can be used for synthetic water treatment It can also be used as a methylating agent to synthesize quaternary ammonium salt fungicides, antistatic agents, softeners and other products. [0003] Dimethyl phosphite is generally produced by reacting phosphorus trichloride and methanol in industry: [0004] PCl 3 +3CH 3 OH→(CH 3 O) 2 POH+2HCl↑+CH 3 Cl↑ [0005] The reaction process and mechanism are: [0006] PCl 3 +CH 3 OH→CH 3 OPCl 2 +HCl↑ (1) [0007] CH 3 OPCl 2 +CH 3 OH→(CH 3 O) 2 PCl+HCl↑ (2...

AI Technical Summary

Problems solved by technology

[0014] At present, the industrial production of dimethyl phosphite has been using the batch method of single-pot reaction and single-pot rectification. The reaction materials are fed through the high-level tank, and the measurement control is difficult, and the reaction needs to be controlled below 55°C. , frequent operations, high labor intensity, long production cycle and low equipment capacity

At the same time, the heat of reaction needs to be removed by freezing during the reaction process, and the material needs to be heated during deacidification, so the energy utilization rate in the production process is low

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