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:
Oct. 27, 1998
Filed:
Jun. 05, 1995
Eric Garcin, Lyon, FR;
Francis Luck, Noisy/le/Grand, FR;
Raymond Surantyn, St. Martin Du Tertre, FR;
Rhone-Poulenc Chimie, Courbevoie Cedex, FR;
Abstract
Impure gas streams containing contaminating amounts of NO.sub.x, e.g., automotive exhaust fumes and industrial waste gases, are purified by contacting same, in the presence of ammonia, at an elevated temperature, with a catalyst composition which comprises an inorganic oxide support substrate having a catalytically effective amount of a metal oxide active phase deposited thereon, such support substrate comprising at least one alumina, aluminate, titanium dioxide and/or zirconium dioxide and such catalytically active phase comprising at least one vanadium oxide and/or molybdenum oxide and/or tungsten oxide, the surface of the support substrate being chemically bonded to the metals V and/or Mo and/or W and the catalyst being devoid of V.sub.2 O.sub.3 and/or MoO.sub.3 and/or WO.sub.3 crystalline phases, and thereby selectively reducing such NO.sub.x values while minimizing the formation of N.sub.2 O.