Reduction in the quantity of NO.sub.x in lean exhaust gas of motor vehicle engines

US5354720A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Jurgen Leyrer · Rheinfelden (Baden), DE
• Egbert Lox · Hanau, DE
• Bernd Engler · Hanau, DE

Key dates

• Filing date: Mar 4, 1993
• Grant date: Oct 11, 1994
• Expiry date: Mar 4, 2013

Classification

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

Abstract

A catalyst is described for reducing the quantity of nitrogen oxides in lean exhaust gas of motor vehicle engines. The catalyst contains, on a structure reinforcing body, a first catalytic coating of an aluminum oxide and/or cerium oxide of large surface area impregnated with a mixture of iridium and platinum as catalytically active noble metal components. A second catalytic coating including a zeolite of the mordenite type containing copper and/or iron is applied to the first coating layer.