Gold selective ion exchange resins
CA 2005259 C · Owner: Mintek · Inventors: Green, Brian Russell; Tyc, Irene; Schwellnus, Adriana Hester
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A gold selective ion exchange resin and process for the recovery of gold from solutions thereof is described. The resin has a macroporous structure and functional groups selected from alkylamine groups wherein the alkyl chain has between 3 and 6 carbon atoms, preferably tributylamine groups. The functional group content of the resin is from 0,4mmol/g to 1,8mmol/g and the water retention capacity is at least 30%. The process for recovering gold involves adsorption thereof onto such resin, optionally directly from a slurry and, elution preferably using a thiourea solution.
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 12, 1989 and granted November 3, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 12, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 12, 2011.
- 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.