Process for the preparation of urea
CA 2445589 C · Owner: Stamicarbon B.V. · Inventors: Mennen, Johannes Henricus
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Process for the preparation of urea from ammonia and carbon dioxide in which a urea synthesis solution containing urea ammonium carbamate and unconverted , ammonia is formed in a synthesis zone a part of the urea synthesis solution being transferred from the synthesis zone to a medium-pressure treatment zone operating at a pressure of 1-4 Mpa, and a gas stream from the medium-pressure treatment zone being absorbed into the low-pressure ammonium carbamate solution from the urea recovery section.
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 April 24, 2002 and granted June 28, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 24, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 24, 2024.
- 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.