PGM-free washcoats for catalyzed diesel particulate filter applications

US7030054B2 · kind B2 · utility

Assignee

• Ford Global Technologies, LLC · US

Inventors

• Albert Chigapov · Aachen, DE
• Alexei Dubkov · Aachen, DE
• Brendan Patrick Carberry · Aachen, DE
• Robert Walter McCabe · Novi, US

Key dates

• Filing date: Apr 18, 2003
• Grant date: Apr 18, 2006
• Expiry date: Oct 21, 2023

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S502/525
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

The present invention provides new platinum group metal (“PGM”) free catalytic compositions that comprise silver and/or cobalt stabilized ceria. These compositions facilitate soot oxidation during the regeneration of diesel particulate filters (DPF) thereby replacing PGM formulations. The compositions of the invention are particularly useful as washcoat compositions for DPFs as part of an automotive after-treatment system. Among the formulations tested, the silver-stabilized ceria and cobalt-stabilized ceria formulations e.g. can oxidize soot at 250–300° C. in the presence of NO2 and oxygen, while silver-stabilized ceria can oxidize diesel soot even in the presence of oxygen as the sole oxidizing agent at these temperatures. A perovshite composition containing Ag—La—Mn was very active at temperatures above 300° C.