Patent Number: 6,309,617

Title: Solid for storing/releasing nitrogen oxides as well as nitrogen oxide storage catalyst

Abstract: An Ag-containing solid, such as Ag.sub.2 O, Ag.sub.2 CO.sub.3, and AgOH, is used for storing/releasing nitrogen oxides in an exhaust gas from an engine during controlled cycling of the .lambda.-value of the exhaust gas. The nitrogen oxides are stored at .lambda.-values of the gas greater than 1 in the Ag-containing solid and the nitrogen oxides are released at .lambda.-values of the gas less than or equal to 1 from the Ag-containing solid. The Ag-containing solid may include a precious metal or a microporous carrier, for example, ZrO.sub.2, SiO.sub.2, TiO.sub.2, Si--Al mixed oxide, and zeolites.

Inventors: Andorf; Renato (Meckenbeuren, DE), Plog; Carsten (Markdorf, DE), Schaeffner; Guido (Horgenzell, DE)

Assignee: Dornier GmbH

International Classification: B01D 53/94 (20060101); F01N 3/08 (20060101); B01D 053/56 (); B01D 053/94 ()

Expiration Date: 10/30/2018