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:
Dec. 06, 2016
Filed:
Jan. 21, 2015
Sumitomo Metal Mining Co., Ltd., Tokyo, JP;
Shinichiro Nakamura, Tokyo, JP;
Osamu Nakano, Tokyo, JP;
SUMITOMO METAL MINING CO., LTD., Tokyo, JP;
Abstract
A hydrometallurgical method for nickel oxide ores, whereby the pH of a neutralized solution can be stabilized. The hydrometallurgical method comprises a sulfuric acid leaching step of leaching an ore slurry of a nickel oxide ore with sulfuric acid, a neutralization step of neutralizing a crude nickel sulfate aqueous solution by adding a neutralizing agent thereto, and a dezincification step of removing zinc as zinc sulfide by adding a sulfurizing agent to a neutralized solution; wherein in the neutralization step, the amount of the neutralizing agent added is adjusted using, as an index, a neutralizing agent addition ratio that indicates the amount of the neutralizing agent added relative to the amount of free sulfuric acid in the crude nickel sulfate aqueous solution.