Oil soluble alkoxylated surfactants from lignin
CA 2092169 A1 · Owner: Texaco Development Corporation · Inventors: Dague, Michael Garrison; Naae, Douglas Gene; Dunn, Nancy Gee
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
OIL SOLUBLE ALKOXYLATED SURFACTANTS FROM LIGNIN (D#78,936-F), ABSTRACT OF THE INVENTION A method of producing oil soluble surfactants from lignin is disclosed, along with a method for recovering oil from underground formations by means of a surfactant flooding system containing these lignin surfactants. Lignin is reduced in the presence of a carbon monoxide or hydrogen reducing agent at high temperature and pressure, alkoxylated with an .alpha.-olefin epoxide and then changed into oil soluble lignin surfactants by a reaction selected from the group consisting of sulfonation sulfation and alkoxysfulation.
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 March 22, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 22, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 22, 2015.
- 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.