Patents by Inventor Durk Ykema

Durk Ykema 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).

  • Star shaped alumina extrudates and catalyst based thereon
    Patent number: 7351393
    Abstract: This invention is directed to star shaped alumina extrudates with a pore volume in the pores of a diameter over 1000 nm, as determined by mercury porosity, of at least 0.05 ml/g and a total pore volume between 0.5-0.75 ml/g. The extrudates have a length of between 2-8 mm, a length to diameter ratio of between 1-3, a side crushing strength of at least 50 N and a bulk crushing strength of at least 1 MPa.
    Type: Grant
    Filed: November 4, 1999
    Date of Patent: April 1, 2008
    Assignee: Engelhard Corporation
    Inventors: Cornelis Roeland Bayense, Durk Ykema