Method for cleaning internal combustion engine exhaust gases

US8397488B2 · kind B2 · utility

Assignee

• UMICORE AG & CO. KG · DE

Inventors

• Anke Woerz · Frankfurt, DE
• Wilfried Mueller · Karben, DE
• Martin Votsmeier · Bruchköbel, DE
• Franz Dornhaus · Scheinfeld, DE
• Martin Roesch · Rodgau, DE

Key dates

• Filing date: Oct 27, 2010
• Grant date: Mar 19, 2013
• Expiry date: Sep 28, 2031

Classification

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

Abstract

Described is a method for cleaning the exhaust gases of internal combustion engines, which method is suitable for reducing harmful gases and particle emissions. Here, the exhaust gas to be cleaned is conducted, under operating conditions, with a discontinuous profile of the air ratio λ across a wall-flow filter substrate which comprises a catalytically active coating containing one storage material. The storage material is suitable for temporarily storing one or more exhaust-gas components under certain operating conditions and releasing said exhaust-gas components again in a targeted fashion in the event of a suitable change in the operating conditions. The coating is configured such that the component has a gradient of the storage material concentration and/or of the total coating amount, with the highest concentration of the storage material in the longitudinal direction of the component being present on the inflow side. At least 60% by weight of the storage material in relation to its total amount is present in the walls between inflow and outflow ducts, and at least 50% by weight of the storage material in relation to its total amount is present in a first, inflow-side zone in…