Method for purifying aqueuous liquids using a scavenger consisting of powdered activated carbon enveloped in polyvinyl alcohol, and corresponding scavenger
CA 2081730 C · Owner: Ceca S.A. · Inventors: Lini, Hedi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
he invention involves a purification process for aqueous liquids using a purification agent consisting of powdered activated carbon in an envelope of water-soluble polyvinyl alcohol film. The process includes: adding the purification agent to and dispersing it in the liquid to be purified keeping the liquid to be purified in contact with the purification agent drawing off and eventually filtering the purified liquid. The process is characterized by the fact that the activated carbon is a chemical carbon with a pore volume exceeding 1.5 cm3/g a specific BET surface greater than 1700 m2/g an iodine number exceeding 145 and a blue number greater than 19 and chosen in such a way that no trace …
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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 October 29, 1992 and granted August 19, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 29, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 29, 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
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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.