Process for removing metallic corrosion products from a contaminated catalyst solution produced on carbonylation of methanol and/or methyl acetate and/or dimethyl ether

US4985383A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Heinz Erpenbach · Cologne, DE
• Winfried Lork · Lechenich, DE
• Andreas Seidel · Dormagen, DE
• Peter Prinz · Ethel, US

Key dates

• Filing date: Jan 26, 1990
• Grant date: Jan 15, 1991
• Expiry date: Jan 26, 2010

Classification

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

Abstract

In a process for removing the metallic corrosion products from a contaminated catalyst solution produced on carbonylation of methanol and/or methyl acetate and/or dimethyl ether and containing carbonyl complexes of noble metals from group VIII of the Periodic Table of the elements, quaternary organo-phosphorus compounds as organic promoters, metallic corrosion products and acetic acid, acetic anhydride, ethylidene diacetate and, in some cases, undistillable organic compounds, the catalyst solution is treated with water, the noble metal carbonyl complex and the undistillable organic compounds, if present, being precipitated, while the organic promoter and the metallic corrosion products remain in solution; the aqueous phase is separated from the precipitated noble metal carbonyl complex and the organic promoter is extracted from the aqueous phase using C.sub.4 -C.sub.8 -alkanols, the promoter is recovered by evaporating the extractant, the promoter is recombined with the precipitated nobel metal carbonyl complex and with the undistillable organic compounds, if present, and the purified catalyst solution is recycled into the process after addition of acetic acid and/or acetic anhydri…