System and method for continuously producing diethyl methylphosphite

Abstract

The invention provides a system for continuously producing diethyl methylphosphite. The system comprises a rapid mixing reactor and a material circulation subsystem; a rapid mixing component is arranged at the inlet of the rapid mixing reactor and comprises a first liquid inlet and a second liquid inlet; the second liquid inlet is used for feeding a material containing methylphosphonous dichloride; the material circulation subsystem comprises a filter, a material distribution unit, an acid-binding agent premixer and a heat exchanger which are connected in sequence; the filter is also providedwith a solid waste outlet; the material distribution unit is also provided with a diethyl methylphosphite outlet; the acid-binding agent premixer is also provided with a reaction raw material inlet and an acid-binding agent inlet; and the inlet of the filter is connected with the outlet of the rapid mixing reactor, and the outlet of the heat exchanger is connected with the first liquid inlet. A method for continuously producing diethyl methylphosphite by adopting the system can realize large-scale continuous production of diethyl methylphosphite, and has the advantages of high product yield, stable production and high production benefit.

Description

technical field [0001] The present invention relates to the technical field of diethyl methylphosphonite, more specifically, relates to a system and method for continuous production of diethyl methylphosphonite. Background technique [0002] Diethyl methylphosphonite (CH 3 P(OEt) 2 ) is an important refined intermediate, widely used in the production of flame retardants and herbicides, generally through methyl phosphine dichloride (CH 3 PCl 2 ) reacted with ethanol; the reaction formula of this process is CH 3 PCl 2 +2EtOH→CH 3 P(OEt) 2 +2HCl, the generated hydrogen chloride will further undergo an acidolysis side reaction with diethyl methylphosphonite, thereby reducing the yield of the target product. In order to avoid acidolysis of diethyl methylphosphonite by hydrogen chloride, it is necessary to neutralize hydrogen chloride in time by introducing an acid-binding agent. These reactions belong to the fast reaction process, and the mixing degree of each component s...

AI Technical Summary

Problems solved by technology

But adopting stirred tank to produce diethyl methylphosphonite has the following obvious defects: (1) the mechanical agitation of stirred tank is difficult to realize the quick and uniform mixing of material, has limited acid-binding agent and hydrogen chloride reaction, and methylphosphonous acid diethyl Ethyl ester is prone to acidolysis, and the yield of the target product is low; (2) The heat exchange components in the stirred tank are limited by the stirring paddle, and the processing capacity of a single device is low. In industrial scale production, multiple tanks are often required to be operated in parallel, and the equipment cost is high; (3) Due to the presence of rotating parts of the stirring paddle in the stirred tank, the sealing requirements of the reactor are more stringent

However, the internal structure of the microreactor is relatively complex, the production capacity of a single reactor is low, and the equipment cost for large-scale production is high; at the same time, the microreactor channel is small, which is not suitable for acid-binding neutralization reactions where solid particles are generated

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