Process for regenerating thiosulphate from a gold leaching stream
CA 2454013 C · Owner: Buisman, Cees Jan Nico · Inventors: Picavet, Merijn Amilcare; Buisman, Cees Jan Nico
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A new process of regenerating thiosulphate from a spent thiosulphate solution comprises the steps of: (a) reacting the spent thiosulphate solution with sulphide to produce elemental sulphur and a regenerated thiosulphate solution (b) separating the elemental sulphur from the regenerated thiosulphate solution (c) biologically reducing the separated elemental sulphur to produce sulphide and (d) returning the sulphide from step (c) to step (a). This can. be applied in a process of extracting noble metals such as gold from a gold-containing slurry by contacting the slurry with a solution containing thiosulphate ions and oxygen to produce a gold thiosulphate solution contacting the gold …
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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 23, 2003 and granted March 13, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 23, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 23, 2025.
- 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
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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.