Carrier catalyst, process for its preparation, and its use for the preparation of vinyl acetate

US5292931A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Peter Wirtz · Königstein, DE
• Karl-Fred Worner · Uhingen, DE
• Friedrich Wunder · Flörsheim, DE
• Klaus Eichler · Laufenburg (Baden), DE
• Gunter Roscher · Kelkheim, DE
• Ioan Nicolau · Port Aransas, US

Key dates

• Filing date: Apr 7, 1993
• Grant date: Mar 8, 1994
• Expiry date: Apr 7, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C67/055
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

The invention relates to a process for the preparation of a catalyst which contains palladium and/or compounds thereof and alkali metal compounds, and additionally cadmium compounds and/or gold and/or compounds thereof, on support particles which have been pressed from SiO.sub.2 or an iO.sub.2 -Al.sub.2 O.sub.3 mixture with the aid of a binder which comprises PA0 a) washing the roasted support particles with an acid which does not react with SiO.sub.2 or SiO.sub.2 -Al.sub.2 O.sub.3 mixtures, until no further cations of the binder employed during pressing of the support particles are released from the support particles; PA0 b) then impregnating the support particles with palladium, and gold or cadmium; PA0 c) then bringing the impregnated support particles into contact with a solution of a base at least until the thickness of the nobel metal shell generated in this way on the support particles no longer changes substantially; and PA0 d) then impregnating the support particles with an alkali metal compound. A shell-like distribution of the palladium and if appropriate of the gold in the support particles is generated in this manner. Furthermore, the invention relates to a catalyst pr…