Recovery of caprolactam from oligomers and/or polymers of caprolactam

US5360905A · kind A · utility

Assignee

• BASF SE

Inventors

• Hugo Fuchs · Ludwigshafen, DE
• Claus-Ulrich Priester · Ludwigshafen, DE
• Gerald Neubauer · Weinheim, DE
• Erwin Brunner · Meiningen, DE
• Josef Ritz · Ludwigshafen, DE
• Michael Kopietz · Frankfurt, DE

Key dates

• Filing date: May 14, 1993
• Grant date: Nov 1, 1994
• Expiry date: May 14, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D201/12
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for recovering caprolactam from oligomers and/or polymers of caprolactam comprises the following steps: PA1 a) treating oligomers and/or polymers of caprolactam with from 1 to 20 parts by weight of water per part by weight of oligomer or polymer at from 200.degree. to 350.degree. C. under superatmospheric pressure with a residence time of from 0.5 to 10 hours to form an aqueous reaction mixture comprising polycaprolactam, monomeric caprolactam and oligomers thereof, and PA1 b) passing the aqueous reaction mixture obtained in a) into a fluidized bed of alumina at from 250.degree. to 400.degree. C. to obtain a mixture of steam and caprolactam.