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:
Jul. 13, 1999
Filed:
Mar. 10, 1997
Mohinder S Chattha, Northville, MI (US);
Tjenga E Hoost, Redford, MI (US);
Robert J Kudla, Warren, MI (US);
Ford Global Technologies, Inc., Dearborn, MI (US);
Abstract
The invention is a nitrogen oxide trap comprising a porous support of alumina; and loaded thereon materials consisting essentially of particular amounts of: (I) tungstophosphoric acid and (II) precious metal selected from platinum, palladium, rhodium and mixtures thereof. The trap is useful for trapping nitrogen oxides produced in the exhaust gas generated by an internal combustion gasoline engine during lean-burn operation of the engine. The trap releases the nitrogen oxides during decreased oxygen concentration in the exhaust gas. The desorbed NOx may be converted over the precious metal to N.sub.2 and O.sub.2 by reductants like hydrocarbons present in the exhaust gas.