Patents by Inventor Ulf H. Haagensen

Ulf H. Haagensen 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).

  • Purification of aqueous reaction or washing medium containing cellulose ethers
    Patent number: 5482634
    Abstract: In a process for purifying an aqueous liquid reaction and/or washing medium containing i) hot water-insoluble cellulose ethers and ii) hot water-soluble cellulose ethers and/or macromolecular cellulose ether by-products, in a purification step a) the aqueous medium has a temperature above the gel point of the hot water-insoluble cellulose ether and gelled cellulose ether is separated from the aqueous medium by means of a solid-bowl centrifuge or a plate separator and in a purification step b) the remaining aqueous liquor is treated by ultrafiltration at a concentration ratio of at least 40.
    Type: Grant
    Filed: June 13, 1994
    Date of Patent: January 9, 1996
    Assignee: The Dow Chemical Company
    Inventors: Yvonne M. Goerlach-Doht, Hans P. Schneider, Juergen Hermanns, Ulf H. Haagensen