Process for separating iodine and its compounds from the carbonylation products obtained by subjecting dimethylether, methyl acetate or methanol to a carbonylation reaction

US4664753A · 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: Aug 6, 1984
• Grant date: May 12, 1987
• Expiry date: Aug 6, 2004

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C67/60
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The disclosure relates to a process for separating iodine and its compounds from the carbonlyation products acetic acid, acetic anhydride or ethylidene diacetate obtained by subjecting dimethylether, methyl acetate or methanol to a carbonylation reaction. For reducing the quantity of total iodine contaminating the carbonlyation products to less than 20 ppb iodine, the disclosure provides for the carbonylation products to be treated at temperatures of 20.degree. to 250.degree. C. with an alkyl or aryl phosphine or a heterocyclic aromatic nitrogen compound and at least one of the metals copper, silver, zinc or cadmium or their compounds and to be distillatively separated from the iodine thereby fixed in non-volatile form.