Electrolytic reduction of alumina
US4865701A · kind A · utility
Inventors
Key dates
| Filing date | Aug 31, 1988 |
| Grant date | Sep 12, 1989 |
| Priority date | — |
| Expiry date | Aug 31, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25C3/08
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Alumina is reduced to molten aluminum in an electrolytic cell containing a molten electrolyte bath composed of halide salts and having a density less than alumina and aluminum and a melting point less than aluminum. The cell comprises a plurality of vertically disposed, spaced-apart, non-consumable, dimensionally stable anodes and cathodes. Alumina particles are dispersed in the bath to form a slurry. Current is passed between the electrodes, and oxygen bubbles form at the anodes, and molten aluminum droplets form at the cathodes. The oxygen bubbles agitate the bath and enhance dissolution of the alumina adjacent the anodes and inhibit the alumina particles from settling at the bottom of the bath. The molten aluminum droplets flow downwardly along the cathodes and accumulate at the bottom of the bath.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.