Aluminium electrowinning with metal-based anodes
CA 2393429 A1 · Owner: De Nora, Vittorio · Inventors: Duruz, Jean-Jacques; De Nora, Vittorio
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the electrowinning of aluminium from alumina dissolved in a fluoride-based molten electrolyte in a cell operating at reduced temperature typically below 870~C, utilising nickel-alloy based anodes in particular , nickel-iron alloy anodes. The electrolyte contains AlF3 in such a high concentration, usually above 20 weight% in addition to cryolite, that , fluorine-containing ions rather than oxygen ions are oxidised on the anodes. However, only oxygen is evolved, the evolved oxygen being derived from the dissolved alumina present near the anodes. The anodes may be porous at the surface so as to provide a high active surface area for operation at low current density.
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed December 6, 2000. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 6, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 6, 2022.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.