US 11,788,170 B2
Precious metals recovery
Dave Shuck, Billings, MT (US); Jerry Kolstad, Billings, MT (US); Mark Rapkoch, Laurel, MT (US); and Grenvil Marquis Dunn, Gauteng (ZA)
Assigned to Stillwater Mining Company, Billings, MT (US)
Filed by STILLWATER MINING COMPANY, Billings, MT (US)
Filed on May 28, 2019, as Appl. No. 16/423,960.
Application 16/423,960 is a continuation of application No. 15/138,770, filed on Apr. 26, 2016, granted, now 10,316,388.
Application 15/138,770 is a continuation of application No. 13/976,576, granted, now 9,347,113, previously published as PCT/US2012/067635, filed on Dec. 3, 2012.
Claims priority of provisional application 61/566,596, filed on Dec. 2, 2011.
Prior Publication US 2019/0284659 A1, Sep. 19, 2019
This patent is subject to a terminal disclaimer.
Int. Cl. C22B 3/12 (2006.01); C22B 11/00 (2006.01); C22B 3/42 (2006.01); C22B 3/44 (2006.01); C22B 3/14 (2006.01); C22B 3/10 (2006.01); C22B 3/16 (2006.01); C22B 3/22 (2006.01); C22B 11/06 (2006.01)
CPC C22B 11/04 (2013.01) [C22B 3/10 (2013.01); C22B 3/12 (2013.01); C22B 3/14 (2013.01); C22B 3/165 (2013.01); C22B 3/22 (2013.01); C22B 3/42 (2013.01); C22B 3/44 (2013.01); C22B 11/06 (2013.01); Y02P 10/20 (2015.11)] 16 Claims
OG exemplary drawing
 
1. A method comprising:
evaporating a liquid stream comprising an alkali metal chloride and a substituted quaternary amine to form a crystal slurry in at least one evaporator maintained at a boiling temperature between 100° C. and 150° C.;
contacting the crystal slurry with a stream comprising at least one of palladium, rhodium, and platinum and comprising negligible amounts of copper, iron, nickel, lead, cobalt, aluminum, calcium, bismuth zinc, sulfur, selenium, tellurium, arsenic, ruthenium, silver and gold.