Process for the purification of a crude carboxylic acid slurry
CA 2505976 A1 · Owner: Arnold, Ernest William, Iii · Inventors: Mcclanahan, Wayne (Deceased); Arnold, Ernest William, Iii; Carrell, Harry Lee
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is a process to produce a purified carboxylic acid product. The process comprises removing impurities from a crude carboxylic acid slurry in a solid-liquid displacement zone to form a slurry product. The slurry product if further treated in a staged oxidation zone and a crystallization zone to from a crystallized product. The crystallized product is further cooled in a cooling zone and subsequently filtered and dried in a filtration and drying zone. The process produces purified carboxylic acid product having good color and low impurity levels without the use of purification steps like hydrogenation.
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 December 3, 2003. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 3, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 3, 2025.
- 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.