The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 06, 1986
Filed:
May. 18, 1981
Applicant:
Inventors:
Katsuyuki Ohtsuka, Tokai, JP;
Ryukichi Mizuno, Tokai, JP;
Hitoshi Miyazaki, Tokai, JP;
Toshio Fukuzuka, Kobe, JP;
Kazutoshi Shimogori, Kobe, JP;
Hiroshi Satoh, Suita, JP;
Fumio Kami Kubo, Kobe, JP;
Assignees:
Doryokuro Kakunenryo Kaihatsu Jigyodan, Tokyo, JP;
Kabushiki Kaisha Kobe Seiko Sho, Kobe, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C23F / ; C23F / ;
U.S. Cl.
CPC ...
422-7 ; 241D / ; 252626 ; 422-3 ; 422-9 ; 422 12 ;
Abstract
A method of minimizing corrosion deterioration and hydrogen absorption embrittlement of tantalum encountered in performing acid digestion of organic waste matter put in an acid digestion kettle of tantalum containing high temperature high concentration sulfuric acid includes the addition of nitric acid, nitrous acid, nitrates, nitrites and/or nitrogen oxides to the sulfuric acid bath.