Bath for electrolytic reduction of alumina and method therefor
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.sub.3 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. Removing sulfur from the bath can also minimize cathode deposits. Aluminum formed on the cathode can be removed directly from the cathode.
- Inventors:
-
- Seattle, WA
- Lynnwood, WA
- Bulleen, AU
- Issue Date:
- Research Org.:
- Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
- OSTI Identifier:
- 874896
- Patent Number(s):
- 6485628
- Application Number:
- 09/721,836
- Assignee:
- Northwest Aluminum Technology (The Dalles, OR)
- Patent Classifications (CPCs):
-
C - CHEMISTRY C25 - ELECTROLYTIC OR ELECTROPHORETIC PROCESSES C25C - PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS
- DOE Contract Number:
- 310468-A-UF
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- bath; electrolytic; reduction; alumina; method; aluminum; molten; electrolyte; following; ingredients; alfsub3; salt; selected; consisting; naf; kf; lif; 0004; wt; 02; based; total; weight; transition; metal; compound; example; fluoride; oxide; carbonate; nickel; iron; copper; cobalt; molybdenum; employed; combination; vessel; containing; non-consumable; anode; dimensionally; stable; cathode; employing; improve; wetting; reducing; eliminating; formation; non-metallic; deposits; removing; sulfur; minimize; formed; removed; directly; transition metal; removing sulfur; electrolytic bath; /205/
Citation Formats
Brown, Craig W, Brooks, Richard J, Frizzle, Patrick B, and Juric, Drago D. Bath for electrolytic reduction of alumina and method therefor. United States: N. p., 2002.
Web.
Brown, Craig W, Brooks, Richard J, Frizzle, Patrick B, & Juric, Drago D. Bath for electrolytic reduction of alumina and method therefor. United States.
Brown, Craig W, Brooks, Richard J, Frizzle, Patrick B, and Juric, Drago D. Tue .
"Bath for electrolytic reduction of alumina and method therefor". United States. https://www.osti.gov/servlets/purl/874896.
@article{osti_874896,
title = {Bath for electrolytic reduction of alumina and method therefor},
author = {Brown, Craig W and Brooks, Richard J and Frizzle, Patrick B and Juric, Drago D},
abstractNote = {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.sub.3 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. Removing sulfur from the bath can also minimize cathode deposits. Aluminum formed on the cathode can be removed directly from the cathode.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Nov 26 00:00:00 EST 2002},
month = {Tue Nov 26 00:00:00 EST 2002}
}