Process for recovering noble metals belonging to group VIII of the Periodic System of the elements from a contaminated catalyst solution originating from the carbonylation of methyl acetate and/or dimethylether

US4557760A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Heinz Erpenbach · Cologne, DE
• Klaus Gehrmann · Lechenich, DE
• Winfried Lork · Lechenich, DE
• Peter Prinz · Ethel, US

Key dates

• Filing date: May 29, 1984
• Grant date: Dec 10, 1985
• Expiry date: May 29, 2004

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P10/20
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

In this process for recovering noble metals of group VIII from a contaminated catalyst solution originating from the carbonylation of methyl acetate and/or dimethylether (the catalyst solution containing carbonyl complexes of these noble metals, organic or inorganic promoters, undistillable organic contaminants as well as volatiles) the volatiles are distillatively removed from the catalyst solution and the remaining distillation residue is water-treated, whereby the noble metal/carbonyl-complex is precipitated together with the organic contaminants and is separated from the aqueous phase, while the promotor is dissolved and recovered in conventional manner. The noble metals are then set free in elemental form by subjecting the noble metal/carbonyl-complex separated and contaminated with organic polymers at temperatures of 150.degree. to 300.degree. C. to treatment with an ethyleneglycoldialkylether solvent of the formula R(--OCH.sub.2 --CH.sub.2).sub.n --OR, in which n stands for a number of from 1 to 4 and R stands for identical or different alkyl groups having from 1 to 6 carbon atoms. The noble metal can then be recovered by filtration, and the solvent can be freed of organic c…