Catalyst system and use thereof

US8226914B2 · kind B2 · utility

Assignee

• UMICORE AG & CO. KG · DE

Inventors

• Paul Spurk · Weiterstadt, DE
• Stéphanie Frantz · Soest, DE
• Thomas Le Tallec · Sartrouville, FR
• Olivier Teysset · Poissy, FR
• Wilfried Mueller · Karben, DE
• Gerald Jeske · Neuberg, DE

Key dates

• Filing date: Feb 20, 2008
• Grant date: Jul 24, 2012
• Expiry date: Feb 5, 2029

Classification

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

Abstract

Soot filters for removing soot from the exhaust gas of lean-burn engines become blocked with progressive operating duration on account of the deposition of soot, and must therefore be regenerated at regular intervals. It has been found that reliable operation of the soot filter is possible only if an active regeneration is carried out from time to time by increasing the exhaust-gas temperature to the soot ignition temperature. For this purpose, an oxidation catalytic converter is usually arranged upstream of the soot filter, and the exhaust-gas temperature is increased by means of the catalytic combustion of additionally injected fuel. Here, the oxidation catalytic converter is subjected to high temperature loading and therefore ages very quickly. It has surprisingly been found that the ageing of the oxidation catalytic converter can be slowed if said oxidation catalytic converter is split into at least two separate catalytic converters and the distance between said separate catalytic converters is 2 to 30 mm.