Patents by Inventor Dietrich Schliephake

Dietrich Schliephake 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 preparing pure synthetic calcium sulfate semihydrate
    Patent number: 4113835
    Abstract: A process for the purification of phosphate containing impure gypsum to obtain therefrom calcium sulfate semihydrate in a purified form by digesting the phosphate containing gypsum with nitric acid at a temperature between 22.degree. and 100.degree. C, the temperature and nitric acid concentration being regulated such as to dissolve most of the phosphate impurities and to allow the recovery of calcium sulfate semihydrate.
    Type: Grant
    Filed: November 10, 1976
    Date of Patent: September 12, 1978
    Assignee: Veba-Chemie Aktiengesellschaft
    Inventors: Hans-Friedrich Kurandt, Dietrich Schliephake