Method for the manufacture of alumina from bauxite
CA 2118776 C · Owner: Veres, Darrell F. · Inventors: Veres, Darrell F.; Gatha, Prashant (Deceased); Wellborn, William W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for the manufacture of aluminum oxide from bauxite containing iron oxide, silica and titania impurities while avoiding problems associated with using carbon as a reducing agent. The method comprises fusing a mixture of bauxite containing 1 to 5 percent carbon by weight of mixture 3 to 15, percent metallic aluminum by weight of mixture and 5 to 15, percent metallic iron by weight of mixture and removing fused aluminum oxide from an upper layer of the fusion. The invention also includes fused aluminum oxide manufactured by the fusion method of the invention without, further purification, which contains an iron oxide content less than one percent, essentially no aluminum carbide and a …
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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 March 10, 1994 and granted November 3, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 10, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 10, 2016.
- 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.