Extruded SCR filter

US8609047B2 · kind B2 · utility

Assignee

• Johnson Matthey Public Limited Company · GB

Inventors

• Ralf Dotzel · Burgkunstadt, DE
• Rainer Leppelt · Lichtenfels, DE
• Jörg Werner Münch · Lichtenfels, DE
• Hubert Schedel

Key dates

• Filing date: Feb 1, 2011
• Grant date: Dec 17, 2013
• Expiry date: Feb 1, 2031

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T29/49345
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A wall-flow filter comprises a catalyst for converting oxides of nitrogen in the presence of a reducing agent, which wall-flow filter comprising an extruded solid body comprising: 10-95% by weight of at least one binder/matrix component; 5-90% by weight of a zeolitic molecular sieve, a non-zeolitic molecular sieve or a mixture of any two or more thereof; and 0-80% by weight optionally stabilized ceria, which catalyst comprising at least one metal, wherein: the at least one metal is present throughout the extruded solid body alone or in combination with: is also present in a higher concentration at a surface of the extruded solid body; is also carried in one or more coating layer(s) on a surface of the extruded solid body; or both.