Process for regenerating nitrogen-treated carbonaceous chars used for hydrogen sulfide removal
CA 2180476 C · Owner: Hayden, Richard A. · Inventors: Butterworth, Steven L.; Hayden, Richard A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process is provided for the restoration of hydrogen sulfide removal capacity in nitrogen-treated carbonaceous chars which have become exhausted for hydrogen sulfide capacity when used for the removal of hydrogen sulfide from gas streams containing oxygen and water. This process entails washing the spent carbonaceous char with water of sufficient quantity to remove the majority of the hydrogen sulfide reaction products. By the use of this process a significant proportion of the original hydrogen sulfide capacity of the nitrogen-treated carbonaceous char is recovered.
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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 29, 1995 and granted August 31, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 29, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 29, 2017.
- 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.