Multi-layer non-carbon metal-based anodes for aluminum production cells and method
US6077415A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 30, 1998 |
| Grant date | Jun 20, 2000 |
| Priority date | — |
| Expiry date | Jul 30, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25C3/12
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A composite, high-temperature resistant, non-carbon metal-based anode of a cell for the electrowinning of aluminium comprises a metal-based core structure of low electrical resistance, for connecting the anode to a positive current supply, coated with a series of superimposed, adherent, electrically conductive layers. These layers consist of at least one layer on the core structure constituting a barrier substantially impervious to monoatomic oxygen and molecular oxygen; one or more intermediate, protective layers on the oxygen barrier layer which remain inactive in the reactions for the evolution of oxygen gas; and an electrochemically active layer for the oxidation reaction of oxygen ions present at the anode/electrolyte interface into nascent monoatomic oxygen, as well as for subsequent reaction for the formation of gaseous biatomic oxygen. The active layer on the outermost intermediate layer is slowly consumable during electrolysis and protects the intermediate protective layer by inhibiting its dissolution into the electrolyte.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.