Method and device for synthesizing aquacide dichloride

Abstract

The invention discloses a method and device for synthesizing aquacide dichloride. The method comprises the following steps: 1, pumping a mixed solution of dichloroethane, a catalyst, nitrobenzene and 2,2-dipyridyl into a slurry bed reactor through a first centrifugal pump; 2, conducting reacting at a certain temperature and a certain pressure, pumping the reacted materials into a filter through a second centrifugal pump, and regenerating the catalyst in a regenerator; and 3, enabling reaction liquid to enter a centrifugal extractor for extraction separation, wherein a water phase is aquacide, enabling an organic phase to enter an organic phase storage tank, then pumping the organic phase into a mixing kettle through a third centrifugal pump, mixing the organic phase with the catalyst, and allowing the formed mixture to enter the slurry bed reactor through a fourth centrifugal pump for a continuous reaction. According to the invention, pyridine and dichloroethane are used as raw materials, and a continuous production method is adopted, so production efficiency is greatly improved, a process is simple, a solvent is convenient to recycle, the requirements of the reaction on equipment is not high, a process for directly synthesizing the aquacide dichloride from pyridine and dichloroethane is realized, and pollution harmful to the environment is not generated.

Description

technical field [0001] The invention relates to the technical field of herbicide synthesis, in particular to a method and device for synthesizing diquat dichloride. Background technique [0002] The chemical name of diquat is 1,1'-ethylene-2,2'-bipyridine diium salt, which is an important pyridine herbicide, and its pure product is colorless to light yellow crystal, Developed by the Swiss company Syngenta, it often exists in the form of monohydrate dibromide salt. At present, the production method of diquat in China mainly uses 2,2'-bipyridyl and dibromoethane to carry out cyclization reaction in a tank-type batch reactor. This process has a low conversion rate per pass and a long reaction time. The rate is low, and the reaction efficiency is low. [0003] At present, the industrial method of synthesizing diquat is mainly prepared by reacting 2,2'-bipyridine with dibromoethane, while the preparation of other counter ion salts of diquat is relatively difficult. In terms of ...

AI Technical Summary

Problems solved by technology

[0009] The object of the present invention is to provide a method and device for synthesizing diquat dichloride salt. The present invention uses pyridine and dichloroethane as raw materials and adopts a continuous production method, which not only greatly improves production efficiency, but also has simple process and solvent recovery. It is convenient, and the reaction does not require high equipment, which solves the problems existing in the current synthesis process of diquat dichloride, and realizes the process of directly synthesizing diquat dichloride from pyridine and dichloroethane; it is in line with atomic economy in chemical production In principle, no harmful pollution to the environment is produced, and it is a green chemical intermediate production technology to solve the problems raised in the above-mentioned background technology

Images