Process for making sodium metabisulfite
CA 1065121 A · Owner: Allied Chemical Corporation · Inventors: Bean, Samuel L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Improvement in the process for making sodium metabisulfite by contacting a suspension of sodium carbonate in countercurrent stream with sulfur dioxide, which involves passing sulfur dioxide-containing gas sequentially through a first and a second reaction vessel, maintaining an acidic aqueous slurry of sodium metabisulfite in the first reaction vessel and a strongly alkaline aqueous slurry of sodium carbonate in the second reaction vessel continuously feeding sodium carbonate to the second reaction vessel passing strongly alkaline slurry from the second reaction vessel to the first reaction vessel and overflowing excess liquid from the first reaction vessel to the second reaction vessel and …
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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
- Granted October 30, 1979. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 30, 1996.
- 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.