Sulfate removal from chlorate liquor
CA 2048565 C · Owner: Bommaraju, Tilak V. · Inventors: Bommaraju, Tilak V.; Ruthel, Walter W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is a method of removing sulfate ion from an aqueous sodium chlorate liquor. A crystallization temperature is selected between about -15 and about 0°C and the maximum concentration of sodium chlorate that is soluble in the liquor at that temperature is determined. The liquor is diluted so that the concentration of sodium chlorate in the liquor is less than that maximum concentration and the liquor is cooled to that temperature so that the sulfate ion in the liquor crystallizes as sodium sulfate decahydrate but the sodium chlorate does not crystallize.
Read the whole patent
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 August 7, 1991 and granted January 30, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 7, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 7, 2013.
- 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.