Patent · US Expired

Electrolytic reduction of alumina

US5006209A · kind A · utility

48Cited by
2References
65Claims
0Family size

Assignees

Inventors

Key dates

Filing dateFeb 13, 1990
Grant dateApr 9, 1991
Priority date
Expiry dateFeb 13, 2010

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC25C3/18
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

Finely divided particles of alumina are electrolytically reduced to aluminum in an electrolytic reduction vessel having a plurality of vertically disposed, non-consumable anodes and a plurality of vertically disposed, dimensionally stable cathodes in closely spaced, alternating arrangement with the anodes. A horizontally disposed, gas bubble generator is located at the vessel bottom, underlying the cathodes and the spaces between each pair of adjacent electrodes. The vessel contains a molten electrolyte bath composed of (1) NaF+Alf.sub.3 eutectic, (2) KF+AlF.sub.3 eutectic and (3) LiF. The alumina particles are maintained in suspension in the molten electrolyte bath by rising gas bubbles generated at the anodes and at the gas bubble generator during the reduction process.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.