Patents by Inventor Kieth C. Yao

Kieth C. Yao 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).

  • Patent number: 4950382
    Abstract: Dewaxed oils can have their low temperature performance improved by the removal of residual wax by adsorption of said residual wax onto a hydrophobic molecular sieve. The wax-laden hydrophobic molecular sieve is regenerated by use of dewaxing solvents, such as ketones.The dewaxed oils, which have residual wax removed by the present invention, are oils which have been dewaxed by means of solvent dewaxing procedures or by catalytic dewaxing processes. These oils, produced by the combination of conventional-adsorptive trim dewaxing, exhibit superior formulated oils low temperature performance as compared to formulated oils made from oils dewaxed to the same pour point solely by conventional dewaxing by either solvent or catalytic processes practiced under severe conditions (deep dewaxing).
    Type: Grant
    Filed: February 13, 1987
    Date of Patent: August 21, 1990
    Assignee: Exxon Research & Engineering Company
    Inventors: Kieth C. Yao, Michael A. Fefer