The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 04, 2014
Filed:
Dec. 29, 2010
Gongshin Qi, Troy, MI (US);
Chang H. Kim, Rochester, MI (US);
Wei LI, Troy, MI (US);
Steven J. Schmieg, Troy, MI (US);
Gongshin Qi, Troy, MI (US);
Chang H. Kim, Rochester, MI (US);
Wei Li, Troy, MI (US);
Steven J. Schmieg, Troy, MI (US);
GM Global Technology Operations LLC, Detroit, MI (US);
Abstract
A low-oxygen content exhaust flow produced by an engine that is combusting, on average, a stoichiometric mixture of air and fuel generally contains various unwanted gaseous emissions. The exhaust flow is treated by an exhaust aftertreatment system that includes a three-way-catalyst (TWC) and an ammonia-selective catalytic reduction (ammonia-SCR) catalyst positioned downstream from the TWC in a flow direction of the exhaust flow. The ammonia-SCR catalyst includes (1) a base metal ion-substituted zeolite and/or a base metal ion-substituted silicoaluminophosphate and (2) an oxygen storage material selected from the group consisting of a metal oxide or a mixed metal oxide that exhibits oxygen storage and release capacity. The serial arrangement of the TWC and the ammonia-SCR catalyst enhances the conversion of NOto Nin the low oxygen-content exhaust flow produced by the engine and helps prevent ammonia slip to the atmosphere.