Patents by Inventor Hajimu Yamana

Hajimu Yamana 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 improving ruthenium decontamination efficiency in nitric acid evaporation treatment
    Patent number: 4526658
    Abstract: A method for improving ruthenium decontamination efficiency in a nitric acid recovery system in which a nitric acid solution containing ruthenium is subjected to an evaporation treatment in a nitric acid evaporator. The method is characterized by carrying out the evaporation treatment of the nitric acid solution in the presence of hydrazine in a concentration of 20 to 5000 mg per liter of the solution in the evaporator. By the action of hydrazine, the evaporation of ruthenium contained in the solution is suppressed during the evaporation treatment, and hence the ruthenium decontamination efficiency is remarkably improved.
    Type: Grant
    Filed: November 10, 1983
    Date of Patent: July 2, 1985
    Assignee: Doryokuro Kakunenryo Kaihatsu Jigyodan
    Inventors: Kanya Kubota, Hajimu Yamana, Seiichiro Takeda