Tin dioxide-based ceramics as inert anodes for aluminum smelting: A laboratory study

Book · Tue Oct 01 00:00:00 EDT 1996

OSTI ID:371962

Vecchio-Sadus, A M; Constable, D C; Dorin, R; Frazer, E J ^[1]; Fernandez, I; Neal, G S; Lathabai, S; Trigg, M B ^[2]

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1. CSIRO, Port Melbourne, Victoria (Australia). Div. of Minerals
2. CSIRO, Clayton, Victoria (Australia). Div. of Materials Science and Technology

The behavior of tin dioxide-based ceramics as inert anodes was examined in a laboratory-scale aluminum smelting cell over a range of electrolyte compositions with operating temperatures between 830--975 C. Anodes of a nominal composition SnO{sub 2} (96 wt%), Sb{sub 2}O{sub 3} (2 wt%) and CuO (2 wt%), were electrolyzed for 90 min at a current density of {approximately}1 A cm{sup {minus}2}. The corrosion rate was determined from the tin and copper concentrations in the recovered electrolyte, aluminum metal and the fume. The corrosion rates were 12.5, 1.6 and 6.5 mg (Ah){sup {minus}1} in electrolytes with bath ratios 1.5 (975 C), 0.89 (903 C) and 0.74 (830 C), respectively. A four-fold increase in corrosion rate was obtained at open-circuit demonstrating the protection provided by oxygen evolution during electrolysis. A preliminary investigation of the dependence of corrosion rate on firing temperatures and additive (Sb{sub 2}O{sub 3} and CuO) concentrations was conducted using a part-factorial design experiment. Post-electrolysis examination of the anodes using scanning electron microscopy coupled with energy dispersive spectroscopy analysis revealed a depletion of copper from the anode and a build-up of an alumina-rich surface layer under certain conditions.

• OSTI ID: 371962
• Report Number(s): CONF-960202-; ISBN 0-87339-312-0; TRN: IM9641%%39
• Resource Relation: Conference: Annual meeting and exhibition of the Minerals, Metals and Materials Society (TMS), Anaheim, CA (United States), 4-8 Feb 1996; Other Information: PBD: 1996; Related Information: Is Part Of Light metals 1996; Hale, W. [ed.] [Anglesey Aluminum Metal Ltd., North Wales (United Kingdom)]; PB: 1304 p.
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM
ELECTROLYSIS
BENCH-SCALE EXPERIMENTS
ELECTRODES
POWDERS
SINTERING
ANTIMONY OXIDES
COPPER OXIDES
ELECTROLYTES
CHEMICAL COMPOSITION
ELECTROCHEMICAL CELLS
ELECTRIC POTENTIAL
TEMPERATURE DEPENDENCE
CORROSION
OXYGEN
SCANNING ELECTRON MICROSCOPY
X-RAY SPECTROSCOPY
EXPERIMENTAL DATA