Two-layer-three-way catalyst

US9517462B2 · kind B2 · utility

Assignee

• UMICORE AG & CO. KG · DE

Inventors

• Martin Roesch · Rodgau, DE
• Dieter Linder · Hanau, DE
• Raoul Klingmann · Alzenau, DE
• Patrizia Laura De Cola · Ludwigsburg, DE
• Joerg-Michael Richter · Scheinfeld, DE
• Marcus Schmidt · Maumee, US

Key dates

• Filing date: Feb 16, 2008
• Grant date: Dec 13, 2016
• Expiry date: Jun 8, 2032

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/12
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A double-layer three-way catalyst is presented, which is formed from a catalytic coating applied directly to an inert honeycomb and a catalytically active coating thereon, and is suitable especially for cleaning of exhaust gases of motor vehicles with gasoline-operated internal combustion engines. The catalyst contains, in each layer, an active aluminum oxide and a cerium/zirconium mixed oxide, both of which are catalytically activated by palladium. The second layer on the gas side contains not only palladium but also rhodium, which is applied to the active aluminum oxide and the cerium/zirconium mixed oxide of the second layer in addition to the palladium. The cerium/zirconium mixed oxide of the second layer has a higher zirconium oxide content than the cerium/zirconium mixed oxide of the first layer. The catalyst is notable for exceptional activity coupled with outstanding aging stability.