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:
May. 29, 1990
Filed:
Jun. 09, 1988
Louis Hegedus, Rockville, MD (US);
Jean W Beeckman, Columbia, MD (US);
Wie-Hin Pan, Columbia, MD (US);
Jeffrey P Solar, Silver Spring, MD (US);
W. R. Grace & Co.-Conn., New York, NY (US);
Abstract
Catalysts for the selective catalytic reduction of NOx by ammonia are made from porous formed supports having a certain fraction of the pores with pore diameters larger than 600 Angstrom units. Thus macropores can be introduced in a formed TiO.sub.2 support by adding burnout materials or some inorganic oxide prior to forming the titania into the formed support. Alternatively, titania is precipitated onto a porous inorganic oxide such as SiO.sub.2, Al.sub.2 O.sub.3, ZrO.sub.2, AlPO.sub.4, Fe.sub.2 O.sub.3 and B.sub.2 O.sub.3 to form the support. Then conventional DeNOx catalytic metals are added. The support can be made by first impregnating the inorganic oxide particles with titania via a soluble precursor, forming titania and then shaping the coated particles into the desired shape such as a monolith. In a second embodiment, the inorganic oxide particles are first formed into the desired shape and then impregnated with the titania forming material. Barium sulfate can be added to the surface of the porous inorganic oxide to made an improved support.