PRECISION PURIFICATION OF ISOPHORONE NITRILE BY MOLTEN CRYSTALLIZATION

PROBLEM TO BE SOLVED: To provide a technology for improving a treatment method of a product mixture consisting of isophorone nitrile, hydrogen cyanide of unreacted raw material and isophorone, a catalyst, methanol or the like.SOLUTION: There is provided a purification method of isophorone nitrile derived from manufacturing isophorone nitrile from isophorone and hydrogen cyanide in presence of a catalyst, including separating impurities in isophorone nitrile by a molten crystallization. There is provided a purification method of isophorone nitrile wherein the molten crystallization is conducted with one step or multi steps by suspension crystallization or a lamellar crystallization.SELECTED DRAWING: Figure 1 【課題】イソホロンニトリル、未反応原料のシアン化水素及びイソホロン、触媒、メタノール、などからなる生成混合物の処理方法の改善する技術の提供。【解決手段】触媒の存在下におけるイソホロンとシアン化水素からのイソホロンニトリルの製造に由来するイソホロンニトリルを精製する方法において、イソホロンニトリル中の不純物を溶融結晶化によって分離する方法。好ましくは溶融結晶化を、１段階又は多段階で実施し、懸濁結晶化又は層状結晶化によって行う、イソホロンニトリルの精製方法。【選択図】図１