Environmentally-friendly synthesis method for phenylphosphonic dichloride

Abstract

The invention provides an environmentally-friendly synthesis method for phenylphosphonic dichloride. Phosphorus trichloride and benzene used as raw materials are reacted under the catalytic action ofLewis acid ionic liquid; after the reaction is finished, the reaction solution is divided into two layers, wherein one layer is an ionic liquid layer, and the other layer is a mixed solution layer ofphenylphosphonic dichloride, benzene and phosphorus trichloride; through direct solution separation, the ionic liquid layer is extracted, and the extract and the mixed solution layer are combined andthen are distilled at normal pressure and distilled at reduced pressure to obtain a phenylphosphonic dichloride target product respectively; and the ionic liquid is reclaimed after evaporation at thenormal pressure and the reduced pressure for removing imprity. Compared with the traditional industrialized process, the method has the characteristics of little using amount of a catalyst, reclaimable catalyst, easy operation and control, low production cost, environmentally-friendly production process and the like, does not need a de-complexing step, and does not produce a large amount of wasteslag.

Description

technical field [0001] The invention relates to a synthesis method of phenylphosphine dichloride, in particular to an environment-friendly synthesis method of phenylphosphine dichloride, and belongs to the technical field of chemical industry. Background technique [0002] Phenylphosphine dichloride is an important organic intermediate and an important chemical raw material in industry. It is widely used in the synthesis of flame retardants, insecticides, stabilizers, plasticizers, and antioxidants. The current industrial synthesis is to use benzene and PCl 3 in anhydrous AlCl 3 Reaction synthesis under catalysis, the disadvantage of this reaction is that it needs to consume excess AlCl 3 , seriously pollute the environment; on the other hand, phenylphosphine dichloride and AlCl 3 Form a complex and cannot be separated directly. The current industrial product separation method is to first add a dissociating agent to the reaction mixture to dissociate the complex of phenyl...

AI Technical Summary

Problems solved by technology

The current industrial synthesis is to use benzene and PCl 3 in anhydrous AlCl 3 Reaction synthesis under catalysis, the disadvantage of this reaction is that it needs to consume excess AlCl 3 , seriously pollute the environment; on the other hand, phenylphosphine dichloride and AlCl 3 Form a complex and cannot be separated directly. The current industrial product separation method is to first add a dissociating agent to the reaction mixture to dissociate the complex of phenylphosphine dichloride and aluminum trichloride, and then extract the benzene with an organic solvent. Based phosphine dichloride, the commonly used dissociating agents are sodium chloride or sodium chloride and quaternary ammonium salt, phosphorus oxychloride, pyridine, hexane oxide, phosphorus pentoxide, etc., these separation methods have catalysts that cannot be regenerated, Disadvantages such as complicated dissociation and extraction process and heavy environmental pollution

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