Efficient electrowinning of zinc from alkaline electrolytes
CA 2270428 A1 · Owner: Siu, Stanley C. · Inventors: Evans, James W.; Siu, Stanley C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Zinc metal is deposited from an alkali electrolyte solution onto conductive seed particles in an electrowinning cell which yields unusually high current efficiency and low energy consumption. The electrowinning cell is defined by side edge walls (12, 13) tapering toward the bottom and contains internal , partitions (14 15) which divide the interior into a levitation zone or draft tube (16) open at both its upper end (17) and its lower end (18) and two , downflow sections (19, 20).
Read the whole patent
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 November 19, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 19, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 19, 2019.
- 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.