US 12,391,564 B2
Process for purifying potassium chloride
Steve Lockie, Glasgow (GB); and Douglas H. Brown, Glasgow (GB)
Assigned to KLINGE CHEMICALS LIMITED, Glasgow (GB)
Appl. No. 17/597,690
Filed by Klinge Chemicals Limited, Glasgow (GB)
PCT Filed Jul. 14, 2020, PCT No. PCT/GB2020/051691
§ 371(c)(1), (2) Date Jan. 18, 2022,
PCT Pub. No. WO2021/009503, PCT Pub. Date Jan. 21, 2021.
Claims priority of application No. 1910137.7 (GB), filed on Jul. 15, 2019.
Prior Publication US 2022/0259058 A1, Aug. 18, 2022
Int. Cl. C01D 3/14 (2006.01); B01J 45/00 (2006.01); B01J 47/02 (2017.01); C01D 3/06 (2006.01); C01D 3/16 (2006.01)
CPC C01D 3/145 (2013.01) [B01J 45/00 (2013.01); B01J 47/02 (2013.01); C01D 3/06 (2013.01); C01D 3/16 (2013.01); C01P 2006/80 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A process for the preparation of purified potassium chloride comprising the step of at least partially removing one or more class 1 heavy metal impurities selected from the group consisting of lead impurities, arsenic impurities, cadmium impurities and mercury impurities, from potassium chloride process liquor by ion exchange, and the process comprising a recrystallisation step subsequent to the ion exchange, wherein said recrystallisation step is cooling crystallisation.