Patents by Inventor Arthur J. Tielens

Arthur J. Tielens 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 for the recovery of alumina
    Patent number: 4512959
    Abstract: Process for recovering coarsely crystalline alumina hydrate from bauxite according to the Bayer process wherein, in the presence of fine seed crystals, agglomerates are initially formed in a supersaturated sodium aluminate solution at 80.degree. to 65.degree. C. The agglomerates are then conducted through a first cascade of crystallizers and, after cooling to 55.degree. to 45.degree. C., through a second crystalizer cascade. A crystal suspension is extracted from the last crystallizer of the second crystallizer cascade and fractionated into fine seed crystals and coarse product crystals.
    Type: Grant
    Filed: June 21, 1983
    Date of Patent: April 23, 1985
    Assignee: Alcoa Chemie GmbH
    Inventors: Horst Pohland, Arthur J. Tielens