Patents by Inventor Ralph Stadler

Ralph Stadler 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).

  • Method and apparatus for purifying acrylic acid, and acrylic acid purified by the method
    Patent number: 5504247
    Abstract: A method of purifying acrylic acid by fractional crystallization is provided. The method includes the steps of subjecting an acrylic acid containing mixture to a dynamic crystallization stage to recover purified acrylic acid, leaving a residue containing acrylic acid; subjecting the residue to a static crystallization stage to recover an acrylic acid enriched fraction; and recycling the acrylic acid enriched fraction to the dynamic crystallization stage for recovery of purified acrylic acid.
    Type: Grant
    Filed: March 22, 1994
    Date of Patent: April 2, 1996
    Assignee: Sulzer Chemtech AG
    Inventors: Kurt Saxer, Ralph Stadler