Patents by Inventor Thomas L. Grantland

Thomas L. Grantland 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).

  • Processes for cystallizing 4, 4'-dimethyl bibenzoate (DMBB) recovered from polyester byproduct streams
    Patent number: 5801269
    Abstract: Processes for recovering 4,4'-dimethyl bibenzoate (DMBB) from byproduct streams of dimethyl terephthalate (DMT) production are disclosed. The byproduct streams are treated to produce an overhead stream which includes DMBB. In one aspect of the invention, the overhead product stream is added to an organic solvent under conditions sufficient to rapidly form a suspension of crystallized DMBB. In another aspect of the invention, the overhead is dissolved in an appropriate organic solvent and cooled to form a suspension of DMBB crystals in the solvent. A portion of the suspension is removed, and the remaining portion of the suspension centrifuged to recover DMBB crystals. In still another aspect of the invention, the overhead stream is treated with an organic solvent to form a slurry of DMBB crystals, and the resultant slurry thermally treated to increase the concentration of DMBB crystals therein while also solubilizing any organic contaminants.
    Type: Grant
    Filed: April 30, 1997
    Date of Patent: September 1, 1998
    Assignee: Hoechst Celanese Corp.
    Inventors: Carrie A. Feeney, Ida L. Jones, Bennett C. Ward, Thomas M. Kenesson, Charles B. Hilton, Michael R. Ahern, Gregory M. Adams, Edward M. de la Garza, B. Frank Wood, Jr., Thomas L. Grantland, Kan J. Tsai, James L. Ragan