Surfactants from lignin
CA 1287348 C · Owner: Whittington, Lawrence Edward · Inventors: Naae, Douglas Gene; Debons, Francis Eugene; Ledoux, Will Anthony
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of producing surfactants from lignin is disclosed by reducing lignin in the presence of a carbon monoxide or hydrogen reducing agent at high temperature and pressure to produce low molecular weight lignin phenols and subjecting the lignin phenols to one or a combination of several reactions such as alkoxylation, alkylation, sulfonation sulfation, alkoxysulfation, and sulfomethylation. The lignin surfactants so produced can be employed in a surfactant system to recover oil from underground formations.
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
- Granted August 6, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 6, 2008.
- 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.