Processes for recovering citric acid
CA 2106078 C · Owner: Vorhies, Susan · Inventors: Fitzpatrick, Gina; Mcquigg, Donald; Crowe, Ernest
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Described are preferred processes for recovering citric acid from a medium in which it is contained. The citric acid is recovered both effectively and in a form which is readily purifiable. In one preferred process, the citric acid-containing medium is contacted with a solid-phase free base resin having tertiary amine groups to adsorb the citric acid. The citric acid is then desorbed by displacement with a stronger acid, and a citric acid-containing fraction is collected substantially free from contamination by the stronger acid. In another preferred process a citric acid-containing , medium is contacted with a solid-phase polymer having pyridine functions to adsorb citric acid the …
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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 12, 1992 and granted October 29, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 12, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 12, 2014.
- 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.