Process for argon purification
CA 2214557 C · Owner: Tseng, James K. · Inventors: Tseng, James K.; Jain, Ravi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An argon gas stream containing hydrogen carbon monoxide, water vapor, oxygen, carbon dioxide nitrogen and methane is purified by drying the gas stream with adesiccant oxidizing the hydrogen and carbon dioxide to water vapor and carbon dioxide by contact with oxidizing catalysts in the presence of excess oxygen removing the water vapor and carbon dioxide from the gas stream by adsorption removing excess oxygen by chemisorption at elevated temperature and removing the nitrogen and methane by adsorption at cryogenic temperature. Alternatively excess oxygen is removed from the gas stream by adsorption at a cryogenic temperature.
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 September 2, 1997 and granted January 1, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 2, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 2, 2019.
- 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.