Recovery of acrylic acid and/or ethyl acrylate from black acid
CA 1307795 C · Owner: Hoechst Celanese Corporation · Inventors: Dougherty, Edward F.; Paul, James L.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Black acid or the sulfuric acid residue obtained in the manufacture of ethyl acrylate by reaction of ethylene and acrylic acid in the presence of sulfuric acid is heated and distilled in the presence of a solvent for recovery of acrylic acid and ethyl acrylate.
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 September 22, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended September 22, 2009.
- 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.