Method for separating and purifying hafnium and zirconium
CA 2572612 C · Owner: Pellet-Rostaing, Stephane · Inventors: Pellet-Rostaing, Stephane; Lagarde, Stephane; Lemaire, Marc
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention concerns a method for separating hafnium and zirconium from a mixture containing ZrCl4 and HfCl4 the method comprising the following steps: 1) introducing the ZrCl4 and HfCl4 mixture in vapour form into a continuous extractive distillation column; 2) selectively absorbing ZrCl4 and HfCl4 vapours with an extraction solvent circulating counter-current relative to said vapours in the distillation column; 3) drawing a liquid or gaseous ZrCl4 and HfCl4 mixture enriched in ZrCl4; 4) drawing a liquid or gaseous ZrCl4 and HfCl4 mixture enriched in HfCl4; 5) hydrolyzing the mixture obtained at step 4) in an inorganic acid aqueous solution so as to form an aqueous solution having 7 to …
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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 July 7, 2005 and granted September 25, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 7, 2025.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
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Timeline
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.