Process of removing nitrite from a silver nitrate solution
CA 2078691 C · Owner: Popham, Stephen M. · Inventors: Popham, Stephen M.; Chefalo, Patrick M.; Buesing, Robert J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A silver nitrate feed solution comprising nitrite and nitric acid is treated to produce a low-nitrite silver nitrate product solution. In the process the temperature of the feed solution is established in the range of from about 80°C to about the boiling point of the feed solution. The feed solution is introduced into a vessel (10) having a stripping zone (12) containing a contacting element (14) and is dispersed over contacting element (14). The feed solution if flowed counter to and intimately contacted in stripping zone (14) with a motive gas to strip nitrite from solution and from a low-nitrite silver nitrate product solution.
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 February 3, 1992 and granted October 14, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 3, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 3, 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.