US 11,718,532 B2
Preparation method of high purity SiC powder
Gyu Do Lee, Suwon-si (KR); Tae Hee Kim, Pyeongtaek-si (KR); and Chae Young Lee, Cheonan-si (KR)
Assigned to KCindustrial Co., Ltd., Seoul (KR)
Filed by KCindustrial Co., Ltd., Seoul (KR)
Filed on Nov. 22, 2019, as Appl. No. 16/692,036.
Claims priority of application No. 10-2018-0170220 (KR), filed on Dec. 27, 2018; application No. 10-2019-0109045 (KR), filed on Sep. 3, 2019; and application No. 10-2019-0109046 (KR), filed on Sep. 3, 2019.
Prior Publication US 2020/0207630 A1, Jul. 2, 2020
Int. Cl. C01B 32/956 (2017.01); B02C 23/10 (2006.01); B02C 21/00 (2006.01)
CPC C01B 32/956 (2017.08) [B02C 21/00 (2013.01); B02C 23/10 (2013.01); C01P 2004/61 (2013.01); C01P 2004/62 (2013.01); C01P 2004/64 (2013.01); C01P 2006/80 (2013.01)] 9 Claims
 
1. A process for preparing high purity SiC powders, which comprises:
pulverizing waste SiC comprising an impurity, said impurity comprising Fe, and optionally one or more selected from the group consisting of Li, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, and Mo;
classifying the pulverized waste SiC based on a particle size of the pulverized waste SiC;
feeding the classified pulverized waste SiC to a Fe-removal machine;
removing the Fe from the classified pulverized waste SiC in the Fe-removal machine; and
cleaning the waste SiC from which the Fe has been removed,
wherein rate of the feeding the classified pulverized waste SiC to the Fe-removal machine is:
(a) 1 g/s to 50 g/s for the classified pulverized waste SiC with the particle size from 10 nm to 100 μm,
(b) greater than 50 g/s to 1,000 g/s for the classified pulverized waste SiC with the particle size greater than 100 μm to 50 mm, or
(c) 1,000 g/s to 2,000 g/s for the classified pulverized waste SiC with the particle size greater than 50 mm to 100 mm.