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:
Nov. 13, 2007
Filed:
Dec. 03, 2002
Applicants:
Marko Lahtinen, Pori, FI;
Leena Lehtinen, Pori, FI;
Heikki Takala, Pori, FI;
Inventors:
Assignee:
Outotec Oyj, Espoo, FI;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C01G 49/06 (2006.01); C22B 3/44 (2006.01);
U.S. Cl.
CPC ...
Abstract
This invention relates to a method for the removal of iron as hematite from a zinc sulphate solution in atmospheric conditions during the electrolytic preparation of zinc. According to the method, the pH of the iron-containing solution is adjusted to a value of at least 2.7, oxygen-containing gas is fed into the solution and part of the hematite thus formed is recirculated to the precipitation stage.