Patent · US Expired

Apparatus and method for the electrolytic production of metals

US4999097A · kind A · utility

88Cited by
9References
31Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 20, 1989
Grant dateMar 12, 1991
Priority date
Expiry dateJul 20, 2009

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC25C7/025
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

Improved electrolytic cells and methods for producing metals by electrolytic reduction of a compound dissolved in a molten electrolyte are disclosed. In the improved cells and methods, a protective surface layer is formed upon at least one electrode in the electrolytic reduction cell and, optionally, upon the lining of the cell. This protective surface layer comprises a material that, at the operating conditions of the cell: (a) is not substantially reduced by the metal product; (b) is not substantially reactive with the cell electrolyte to form materials that are reactive with the metal product; and, (c) has an electrochemical potential that is more electronegative than that of the compound undergoing electrolysis to produce the metal product of the cell. The protective surface layer can be formed upon an electrode metal layer comprising a material, the oxide of which also satisfies the protective layer selection criteria. The protective layer material can also be used on the surface of a cell lining.

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