Ammonium ion-and ammonia-selective adsorbent and process for preparation of same
CA 2053291 A1 · Owner: Tomita Pharmaceutical Corporation Limited · Inventors: Miyawaki, Keiko; Kamewa, Toshihiro; Okubo, Akira
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides an ammonium ion- and ammonia-selective adsorbent. According to the invention an ammonium ion-selective, adsorbent can be obtained by introducing alkali metal ions capable of ion exchange into a silica-alumina composite oxide having a specific composition, the obtained adsorbent being capable of selectively adsorbing ammonium ions and ammoniacal nitrogen without affecting other components in saewater as well as fresh water, and being capable of keeping the pH value of seawater varied within an extremely narrow range. The adsorbent of the invention is also useful as an adsorbent for adsorption of ammonia gas.
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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 September 10, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 10, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 10, 2012.
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Timeline
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.