DINITRILE PREPARATION METHOD

摘要

The invention relates to a method of preparing dinitriles, involving hydrocyanation of unsaturated nitrile compounds in the presence of a catalyst based on metallic elements in zero oxidation state and organophosphorous ligands. More specifically, the invention relates to a method of recovering a catalyst for the hydrocyanation of unsaturated nitriles into dinitriles from the hydrocyanation medium. The inventive method consists in: controlling the concentration of unsaturated nitriles in the reaction medium originating from the hydrocyanation reaction, in order to obtain a weight concentration of unsaturated nitriles of less than 20 % in said medium; and supplying the aforementioned medium in a decantation step in two phases, namely an upper and lower phase. The lower phase comprises the majority of the catalytic system, while the upper phase essentially comprises the nitriles.