Exhaust gas purification system for the treatment of engine exhaust gases by means of SCR catalyst

US8863507B2 · kind B2 · utility

Assignee

• UMICORE AG & CO. KG · DE

Inventors

• Katja Adelmann · Darmstadt, DE
• Nicola Soeger · Nidderau, DE
• Marcus Pfeifer · Mannheim, DE
• Wolfgang Schneider · Marl, DE
• Gerald Jeske · Neuberg, DE
• Thomas Kreuzer · Karben, DE

Key dates

• Filing date: Mar 18, 2009
• Grant date: Oct 21, 2014
• Expiry date: Oct 26, 2031

Classification

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

Abstract

An exhaust gas purification system (method and device) for the treatment of diesel exhaust gases containing nitrogen oxides and hydrocarbons is disclosed, which comprises the addition of ammonia or of a compound decomposable to ammonia into the exhaust gas stream and the subsequent leading of the exhaust gas stream over two successively arranged SCR catalysts with different properties and compositions. Both SCR catalysts are free of vanadium compounds and only the downstream SCR catalyst contains zeolite compounds. The exhaust gas purification system according to the invention is characterized by good “kick-off” behavior at low temperatures and a simultaneously high conversion performance over a wide temperature range.