Palladium clusters and their use as catalysts

US6197720A · kind A · utility

Assignee

• BASF SE

Inventors

• Daniel Heineke · Ludwigshafen, DE
• Ekkehard Schwab · Neustadt, DE
• Martin Fischer · Ludwigshafen, DE
• Guenter Schmid · Hemhofen, DE
• Monika Baeumle · Essen, DE

Key dates

• Filing date: Nov 23, 1998
• Grant date: Mar 6, 2001
• Expiry date: Nov 23, 2018

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C2531/28
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to colloidal palladium composed of palladium clusters with an average particle diameter 0.2 nm.ltoreq.d.ltoreq.2 nm with at least 80% of the palladium clusters having a particle diameter which differs by not more than 0.2 nm from the average particle diameter d, it being possible for the palladium clusters to have protective ligands on the surface. The invention further relates to a process for preparing a colloidal solution of palladium by reacting a palladium salt with a reducing agent in solution at from 0 to 300.degree. C., employing a branched-chain alcohol as reducing agent and phosphines and/or aromatic nitrogen compounds as protective ligands. The invention further relates to palladium-containing heterogeneous catalysts comprising colloidal palladium applied to a carrier, and to a process for their preparation.