Composition and method for removing hydrogen sulfide from gas streams
CA 2003010 A1 · Owner: Stewart, Robert C. Jr. · Inventors: Stewart, Robert C. Jr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An improved aqueous catalytic oxidation-reduction composition for oxidizing hydrogen sulfide to produce elemental sulfur and a method of removing hydrogen sulfide from a gas stream whereby a gas stream containing hydrogen sulfide is brought into contact with an aqueous catalytic oxidizing reaction composition containing a water soluble polyvalent metal salt having metal in the highest valence state and at least one nonionic surfactant having an HLB of from about 8 to about 10, preferably about 8.5 to about 9, which is adapted to wet the elemental sulfur formed. The nonionic surfactant is present in the reaction solution in an amount sufficient to substantially prevent formation of sulfur …
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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 November 15, 1989. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 15, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 15, 2011.
- 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.