Process for the recovery of catalysts in adipic acid production

US5723098A · kind A · utility

Inventors

• Herbert Salzburg · Leichlingen, DE
• Georg Steinhoff · Unterhaching, DE
• Heiko Hoffmann · Simi Valley, US
• Helmut Kaponig

Key dates

• Filing date: Sep 4, 1996
• Grant date: Mar 3, 1998
• Expiry date: Sep 4, 2016

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/47
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a process for the selective recovery of catalysts used in the production of adipic acid by PA1 (a) separating adipic acid from the reaction solution, PA1 (b) exposing the resultant reaction solution to a sulfonated ion exchanger, thereby binding iron, copper, and vanadium ions to said sulfonated ion exchanger, PA1 (c) separating the ion-exchanger from the reaction solution, PA1 (d) washing the separated ion exchanger with nitric acid to obtain an acid eluate, and PA1 (e) exposing the acid eluate to an ion exchanger modified with aminophosphonic acid groups, thereby removing the iron ions from the acid eluate.