Process for the recovery and reuse of heavy metal oxidation catalyst from residues in the Witten DMT process

US4464477A · kind A · utility

Assignee

• Dynamit Nobel GmbH · DE

Inventors

• Heinrich Bunger · Siegburg, DE
• Rudolf Cordes · Ranzel, DE
• Gerhard Hoffmann · Otterstadt, DE

Key dates

• Filing date: Dec 1, 1981
• Grant date: Aug 7, 1984
• Expiry date: Dec 1, 2001

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/584
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the recovery and reuse of heavy metal oxidation catalyst from residues in the Witten DMT process by extraction, which involves mixing and settling of the residue with water or dilute aqueous solutions of water-soluble, low-molecular, aliphatic monocarboxylic acids at 70.degree.-160.degree. C. and recycling of the extract of the high-boiling distillation residues into the DMT process. The high-boiling distillation residue and the extractant are used in a quantitative ratio of 1:0.9 to 1:0.1, preferably 1:0.5 to 1:0.3.