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:
Jan. 18, 1994
Filed:
Oct. 07, 1991
Clifford N Montreuil, Dearborn, MI (US);
Mordecai Shelef, Birmingham, MI (US);
Ford Motor Company, Dearborn, MI (US);
Abstract
A catalyst system for the selective reduction of gaseous NO.sub.x in the presence of excess oxygen, having a copper-containing ZSM5 zeolite to which a NO.sub.x -containing gas is exposed, and means for introducing a metered volume of finely dispersed, water soluble, oxygen-containing organic compound (alcohol, aldehyde, ketone, ether) into the NO.sub.x -containing gas prior to exposure to the Cu-ZSM5 zeolite. Also, a method of treating automotive exhaust gas emissions, having an excess of oxygen, by the steps of: (a) introducing a water soluble, oxygenated organic compound (steam/oxygenate mixture) into the exhaust gas emissions as a reductant and at a location closely adjacent the source of the exhaust gas generation (in an appropriate amount with respect to the NO.sub.x); (b) substantially immediately exposing the reductant/emission mixture to a transition metal-exchanged high silica ZSM5 zeolite (SiO.sub.2 /Al.sub.2 O.sub.3 of between 10-50) catalyst at a space velocity in the range of 20-80 K hr.sup.-1 ; and (c) sequentially exposing the effluent of such zeolite catalyst to an oxidation catalyst.