Patents by Inventor Chung Z. Wan

Chung Z. Wan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • NOx adsorber catalyst with superior low temperature performance
    Patent number: 8475752
    Abstract: The lean NOx trap catalyst composition of the present invention comprises distinct layers, or zone configuration or multi-brick arrangement. The top layer, front zone or front brick is free of any alkali or alkaline earth NOx trapping components. The under layer, rear zone or rear brick may contain any desirable NOx trapping component in contact with a precious metals group catalyst (e.g., Pt). Catalysts of this invention show wide temperature operation window with superior low temperature performance.
    Type: Grant
    Filed: June 23, 2009
    Date of Patent: July 2, 2013
    Assignee: BASF Corporation
    Inventor: Chung Z. Wan
  • NOx Adsorber Catalyst with Superior Low Temperature Performance
    Publication number: 20090320457
    Abstract: The lean NOx trap catalyst composition of the present invention comprises distinct layers, or zone configuration or multi-brick arrangement. The top layer, front zone or front brick is free of any alkali or alkaline earth NOx trapping components. The under layer, rear zone or rear brick may contain any desirable NOx trapping component in contact with a precious metals group catalyst (e.g., Pt). Catalysts of this invention show wide temperature operation window with superior low temperature performance.
    Type: Application
    Filed: June 23, 2009
    Publication date: December 31, 2009
    Inventor: Chung Z. Wan
  • Three-way catalyst for lean operating engines
    Patent number: 4675308
    Abstract: The invention relates to improved catalytic compositions for controlling gaseous contaminants from the combustion of carbonaceous fuels and, in particular, to three-way catalysts having improved ability to convert unburnt hydrocarbons, carbon monoxide and nitrogen oxides to less harmful forms in the presence of excess oxygen.
    Type: Grant
    Filed: February 20, 1986
    Date of Patent: June 23, 1987
    Assignee: Engelhard Corporation
    Inventors: Chung Z. Wan, Joseph C. Dettling, Kenneth I. Jagel