METHOD FOR PRODUCING N,N'-CARBONYLBIS- DOLLAR G(e)-CAPROLACTAM

摘要

The invention relates to a method for producing N,N'carbonylbis- epsilon -caprolactam by reacting epsilon -caprolactam with phosgene in the presence of a hydrogen chloride-binding agent in an inert organic solvent and isolating the reaction product from the product solution. The isolation comprises the following steps: a) optionally distilling off a part of the organic solvent from the product solution; b) adding water to the product solution; c) removing the organic solvent by azeotropic distillation, optionally while replacing the water distilled off, thereby deploying the product solution of organic solvent; d) allowing the N,N'-carbonylbis- epsilon -caprolactam to crystallize from the solution that is deployed from organic solvent, thereby obtaining an aqueous suspension of N,N'-carbonylbis- epsilon -caprolactam; and e) removing the crystallized product.