Hydrometallurgical method for treating valuable metal raw materials containing chlorides and fluorides
CA 1231536 A · Owner: Outokumpu Oy · Inventors: Poijarvi, Jaakko T.I.; Fugleberg, Sigmund P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The purpose of the method is to remove chlorides and fluorides from a valuable metal raw material by leaching the raw material into sulphuric acid solution and by crystallizing the valuable metal sulphate selectively out of the solution. The valuable metal sulphate crystals are washed in sulphuric acid solution and the recovered dechlorinated and defluorinated crystals are leached into water and conducted into electrolysis. The sulphuric acid solution employed in the raw material leaching and in the crystal washing is preferably the same as the return acid of the electrolysis. Chlorides and fluorides are removed from the mother liquor of crystallization in the bleed.
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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
- Granted January 19, 1988. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 19, 2005.
- 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.