Process for the preparation of substantially pure and colorless trichlorophosphazene phosphoryl dichloride

摘要

The process comprises a treatment with SO2 of the mixture resulting from the reaction of PCl5 and of NH4Cl followed by passing the reaction mixture through a thin-layer evaporator before distillation of the crude P2NOCl5 present in the said mixture. …??This technique makes it possible to remove and subsequently condense SO2, POCl3 and SOCl2 under mild pressure and temperature conditions.