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. 30, 2014
Filed:
Sep. 09, 2010
Applicant:
Khalil Zeaiter, Ottawa, CA;
Inventor:
Khalil Zeaiter, Ottawa, CA;
Assignee:
Elkem Solar AS, Oslo, NO;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C01B 33/02 (2006.01); C01B 33/037 (2006.01); C01B 33/00 (2006.01);
U.S. Cl.
CPC ...
C01B 33/037 (2013.01); C01B 33/02 (2013.01); C01B 33/00 (2013.01); C01P 2006/80 (2013.01);
Abstract
The present invention relates to a method for producing high purity silicon comprising providing molten silicon containing 1-10% by weight of calcium, casting the molten silicon, crushing the silicon and subjecting the crushed silicon to a first leaching step in an aqueous solution of HCl and/or HCl+FeCl3 and to a second leaching step in an aqueous solution of HF and HNO3. The leached silicon particles is thereafter subjected to heat treatment at a temperature of between 1250° C. and 1420° C. for a period of at least 20 minutes and the heat treated silicon is subjected to a third leaching step in an aqueous solution of HF and HNO3.