Process for the manufacture of pure amorphous silica from rocks
CA 2114665 A1 · Owner: Iosef, Alexander · Inventors: Iosef, Alexander
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the manufacture of pure amorphous silica from rocks containing non-crystalline silica is described. The process comprises the steps of: (a) dissolution of said rock in an alkaline solution comprising sodium hydroxide and sodium carbonate obtaining, a solution of sodium silicate; (b) precipitation of pure amorphous silica by adding sodium bicarbonate into said sodium silicate and co-producing sodium carbonate the, weight ratio between SiO2 and Na2O in said dissolution step is in the range of between 0.5 to 3.0; and (c) the sodium carbonate solution is transformed into crystalline sodium bicarbonate, by a salting out reaction with sodium chloride, being recycled to the process. …
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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 February 1, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 1, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 1, 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
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.