Method for purifying caprolactam

US7501047B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Hermann Luyken · Ludwigshafen, DE
• Andreas Ansmann · Wiesloch, DE
• Christoph Benisch · Mannheim, DE
• Peter Baβler · Viernheim, DE
• Rolf Fischer · Heidelberg, DE
• Stefan Maixner · Schwetzingen, DE
• Johann-Peter Melder · Schifferstadt, DE

Key dates

• Filing date: Nov 11, 2003
• Grant date: Mar 10, 2009
• Expiry date: Nov 23, 2025

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D201/16
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The disclosure relates to a process for purifying crude caprolactam. The process involves converting a first mixture of 6-amino capronitrile and water to a second mixture of caprolactam ammonia, water, high boilers and low boilers using a catalyst. The ammonia is removed from the second mixture to obtain a third mixture. Water is removed from the third mixture to give crude caprolactam, high boiler and low boilers. Purified caprolactam is then obtained by a series of distillation steps.