Patents by Inventor Fred Zemlanicky

Fred Zemlanicky 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).

  • Process for synthesizing 4,4'-dihydroxydiphenyl sulfone
    Patent number: 5041677
    Abstract: Process for synthesizing 4,4' bisphenol sulfone involving reacting phenol and sulfuric acid in an inert reaction solvent, and maintaining the reaction solvent at temperatures of about 160 to 200.degree. C. and at a predetermined level sufficient to maintain a saturated 4,4' isomer solution and an unsaturated 2,4' isomer solution, thereby selectively yielding 4,4' bisphenol sulfone with minimal amounts of 2,4' isomer by-product.
    Type: Grant
    Filed: March 28, 1990
    Date of Patent: August 20, 1991
    Assignee: Amoco Corporation
    Inventors: Bernard Cooker, Fred Zemlanicky
  • Process for recovering 4,4' dihydroxydiphenyl sulfone from an isomer mixture
    Patent number: 5001270
    Abstract: A process for recovering 4,4' bisphenol sulfone from an isomer mixture comprising the 4,4' and 2,4' isomers of bisphenol sulfone, which process comprises dissolving the isomer misture in a basic aqueous solution and adding a non-neutralizing amount of acid to selectively precipitate crystals of 4,4' bisphenol sulfone.
    Type: Grant
    Filed: January 18, 1989
    Date of Patent: March 19, 1991
    Assignee: Amoco Corporation
    Inventors: Fred Zemlanicky, Bernard Cooker