Recovery of acrylic acid and/or ethyl acrylate from black acid
CA 2027221 A1 · Owner: Aguilo, Adolfo · Inventors: Aguilo, Adolfo; Smith, Brad L.; Homer, Cecil D. Jr.
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 a distillation zone in the presence of a solvent to form an overhead mixture comprising an organic phase containing ethyl acrylate and solvent, and an aqueous phase containing water solvent and acrylic acid. The aqueous phase is recycled to the distillation zone for recovery of additional acrylic acid value from the organic phase.
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 October 10, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 10, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 10, 2012.
- 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.