Patents by Inventor Jos H. M. Graff

Jos H. M. Graff 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).

  • Phenol recovery from BPA process waste streams
    Patent number: 6133486
    Abstract: The disclosure is of a process for recovering valuable phenol and acetone from by-products of the condensation of phenol and a ketone from a mother liquor obtained for example upon crystallization of a 1:1 adduct of phenol and bisphenol, the mother liquor containing phenol, bisphenol, isomers, contaminant by-products of the condensation reaction of phenol with the ketone and acidic impurities. The mother liquor is distilled/evaporated leaving a tarry residue, which is the feedstock for the process of the invention. The recovery comprises catalytically cracking the feedstock with catalytic proportions of an aromatic sulfonic acid to extract the bisphenol-A values as phenol and acetone.
    Type: Grant
    Filed: December 30, 1998
    Date of Patent: October 17, 2000
    Assignee: General Electric Company
    Inventors: Christianus J. J. Maas, Martin H. Oyevaar, Jos H. M. Graff