Process for the preparation of a pollution control catalyst for internal combustion engine exhaust system/catalytic converter
Catalysts for the purification of exhaust gas
Composite oxide having oxygen absorbing and desorbing capability
Composite oxide having oxygen absorbing and desorbing capability and method for preparing same
Process for producing composite oxide powder containing cerium and zirconium
Catalyst composition containing an intimately combined cerium-zirconium oxide
Catalyst composition containing oxygen storage components
Use of Ce/Zr mixed oxide phase for the manufacture of styrene by dehydrogenation of ethylbenzene
Thermally stable, high-surface-area metal oxides made by organic templating
ApplicationNo. 690511 filed on 10/17/2000
US Classes:502/300, Metal, metal oxide or metal hydroxide502/302, Of lanthanide series (i.e., atomic number 57 to 71 inclusive)502/303, Lanthanum502/304, Cerium502/325, Of Group VIII (i.e., iron or platinum group)502/340, Of Group II (i.e., alkaline earth, Be, Mg, Zn, Cd or Hg)502/349Of Group IV (i.e., Ti, Zr, Hf, Ge, Sn or Pb)
ExaminersPrimary: Silverman, Stanley S.
Assistant: Vanoy, Timothy C.
Attorney, Agent or Firm
Foreign Patent References
International ClassesB01J 021/00
AbstractThe present invention relates to high oxygen ion conducting/oxygen storage (OIC/OS) materials, a catalyst employing the OIC/OS materials, and a method for converting hydrocarbons, carbon monoxide and nitrogen oxides using the catalyst. The OIC/OS materials have significantly higher oxygen storage capacity than that predicted based on Ce content due to the unexpected high and facile redox activity of the added niobium. These materials are further characterized by having a tetragonal crystalline structure under oxidizing conditions (in air) up to about 1,200° C. and a cubic crystalline structure in reducing conditions (5% hydrogen) up to about 1,000° C. for 24 hours. These materials comprise, based upon 100 mole % of the metal component in the material, up to about 95 mole % zirconium, up to about 50 mole % cerium, about 0.5 to about 15 mole % rare earth metal(s), alkaline earth metal(s) or a combination thereof, and about 0.5 to about 15 mole % niobium.