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:
Jul. 10, 2001
Filed:
Feb. 09, 1999
Craig W. Brown, Seattle, WA (US);
Richard J. Brooks, Seattle, WA (US);
Patrick B. Frizzle, Lynnwood, WA (US);
Drago D. Juric, Bulleen, AU;
Northwest Aluminum Technology, The Dalles, OR (US);
Abstract
An electrolytic bath for use during the electrolytic reduction of alumina to aluminum. The bath comprises a molten electrolyte having the following ingredients: (a) AlF,and at least one salt selected from the group consisting of NaF, KF, and LiF; and (b) about 0.004 wt. % to about 0.2 wt. %, based on total weight of the molten electrolyte, of at least one transition metal or at least one compound of the metal or both. The compound may be, for example, a fluoride, oxide, or carbonate. The metal can be nickel, iron, copper, cobalt, or molybdenum. The bath can be employed in a combination that includes a vessel for containing the bath and at least one non-consumable anode and at least one dimensionally stable cathode in the bath. Employing the bath of the present invention during electrolytic reduction of alumina to aluminum can improve the wetting of aluminum on a cathode by reducing or eliminating the formation of non-metallic deposits on the cathode.