ϵ-Caprolactam: new by-product free synthesis routes

Abstract

The production of the nylon precursor ϵ-caprolactam via the Beckmann rearrangement is one of the large industrial processes worldwide. In this work, the state-of-the-art processes are summarized and the two main pathways for new production capacities (the butadiene-based and especially the heterogeneously catalyzed routes starting from benzene/cyclohexanone oxime) are described. Additionally, the new recycling processes to recover caprolactam from waste carpets and some new approaches are described.