Catalyst for reducing nitrogen oxides in oxidizing and reducing atmospheres

US6534439B2 · kind B2 · utility

Assignee

• Degussa-Huels AG · DE

Inventors

• Hans Van Den Tillaart · Alzenau, DE
• Jurgen Leyrer · Rheinfelden (Baden), DE
• Wolfgang Strehlau · Großkrotzenburg, DE
• Egbert Lox · Hanau, DE
• Thomas Kreuzer · Karben, DE
• Carsten Plog · Markdorf, DE
• Renato Andorf · Meckenbeuren, DE
• Norbert Markert · Markdorf, DE
• Thomas Stengel · Friedrichshafen, DE

Key dates

• Filing date: Jul 1, 1999
• Grant date: Mar 18, 2003
• Expiry date: Jul 1, 2019

Classification

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

Abstract

A catalyst for reducing nitrogen oxides in oxidizing and reducing atmospheres which contains iridium on a support material. Silicon dioxide or a dealuminized zeolite in the acid H form with a modulus of more than 20, preferably more than 100, or mixtures thereof are used as support materials. Iridium is deposited on the external surfaces of these support materials with average particle sizes between 10 and 30 nm. The catalyst is particularly suitable for treating exhaust gases from lean-burn gasoline engines or from diesel engines.