Patents by Inventor Mark C. Hsiao

Mark C. Hsiao 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).

  • Catalytic reduction system for oxygen-rich exhaust
    Patent number: 5893267
    Abstract: Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO.sub.x reduction in oxygen-rich vehicle engine exhausts.
    Type: Grant
    Filed: August 5, 1997
    Date of Patent: April 13, 1999
    Assignee: The Regents of the University of California
    Inventors: George E. Vogtlin, Bernard T. Merritt, Mark C. Hsiao, P. Henrik Wallman, Bernardino M. Penetrante
  • Pre-converted nitric oxide gas in catalytic reduction system
    Patent number: 5891409
    Abstract: A two-stage catalyst comprises an oxidative first stage and a reductive second stage. The first stage is intended to convert NO to NO.sub.2 in the presence of O.sub.2. The second stage serves to convert NO.sub.2 to environmentally benign gases that include N2, CO2, and H.sub.2 O. By preconverting NO to NO.sub.2 in the first stage, the efficiency of the second stage for NO.sub.x reduction is enhanced. For example, an internal combustion engine exhaust is connected by a pipe to a first chamber. An oxidizing first catalyst converts NO to NO.sub.2 in the presence of O.sub.2 and includes platinum/alumina, e.g., Pt/Al.sub.2 O.sub.3 catalyst. A flow of hydrocarbons (C.sub.x H.sub.y) is input from a pipe into a second chamber. For example, propene can be used as a source of hydrocarbons. The NO.sub.2 from the first catalyst mixes with the hydrocarbons in the second chamber. The mixture proceeds to a second reduction catalyst that converts NO.sub.2 to N2, CO2, and H.sub.2 O, and includes a gamma-alumina .gamma.-Al.
    Type: Grant
    Filed: April 18, 1997
    Date of Patent: April 6, 1999
    Assignee: The Regents of the University of California
    Inventors: Mark C. Hsiao, Bernard T. Merritt, Bernardino M. Penetrante, George E. Vogtlin
  • Plasma-assisted catalytic reduction system
    Patent number: 5711147
    Abstract: Non-thermal plasma gas treatment is combined with selective catalytic reduction to enhance NO.sub.x reduction in oxygen-rich vehicle engine exhausts.
    Type: Grant
    Filed: August 19, 1996
    Date of Patent: January 27, 1998
    Assignee: The Regents of the University of California
    Inventors: George E. Vogtlin, Bernard T. Merritt, Mark C. Hsiao, P. Henrik Wallman, Bernardino M. Penetrante