Process for the preparation of a mixture of epsilon caprolactam and/or epsilon caprolactam precursors

摘要

Process for the preparation of a mixture of epsilon-caprolactam and epsilon-caprolactam precursors by reductively aminating 5-formylvaleric acid and/or 5-formylvalerate ester(s) in water with hydrogen and an excess of ammonia in the presence of a hydrogenation catalyst, wherein the process is conducted in a reactor of which the inside reactor wall material is a material containing at most 8 wt. % nickel.