The invention relates to a preparation method of diphenyl
phosphine chloride, which belongs to the technical field of
chemical synthesis, and comprises the following steps: adding
benzene and aluminumtrichloride into a reaction kettle, adding
phosphorus trichloride into the kettle while stirring, slowly heating the mixture to 120 DEG C, and carrying out a reaction for 12 hours; stopping heating,cooling the
reaction product to 60 DEG C, adding a decomplexing agent in batches, heating the
reaction product to 80 DEG C, and stirring the
reaction product for 2 hours; desolventizing the reaction product, and rectifying the reaction product to separate out phenyl
phosphine dichloride and diphenyl
phosphine chloride; after the rectification, the product is properly cooled, then slowly adding residual liquid into a 20%
hydrochloric acid solution, stirring the mixture for 2 hours, centrifuging the mixture to obtain a wet decomplexing agent product and an aluminum
chloride solution,
drying thewet decomplexing agent product, and recycling the dried wet decomplexing agent product, and using the aluminum chloride solution for preparing a flocculating agent. According to the method, a new decomplexing agent is used, so that the
solid waste problem of diphenyl phosphine chloride production is solved, the production cost is reduced, and the product has market competitiveness.