US 12,434,979 B2
Preparation method for electronic-grade copper chloride dihydrate
Junqiang Zhu, Guangdong (CN); Huiqian Wang, Guangdong (CN); Qiuqi Liu, Guangdong (CN); Wenbin Xu, Guangdong (CN); Long Chen, Guangdong (CN); and Zengmeng Yu, Guangdong (CN)
Assigned to Dongjiang Environmental Company Limited, Guangdong (CN)
Appl. No. 17/918,364
Filed by Dongjiang Environmental Company Limited, Guangdong (CN)
PCT Filed Dec. 29, 2020, PCT No. PCT/CN2020/140793
§ 371(c)(1), (2) Date Oct. 12, 2022,
PCT Pub. No. WO2022/141045, PCT Pub. Date Jul. 7, 2022.
Prior Publication US 2023/0322575 A1, Oct. 12, 2023
Int. Cl. C01G 3/05 (2006.01)
CPC C01G 3/05 (2013.01) [C01P 2002/72 (2013.01); C01P 2004/03 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A method of preparing an electronic-grade copper chloride dihydrate, comprising the following steps:
(1) dissolving a copper salt in a first hydrochloric acid solution to obtain a copper salt solution;
(2) performing two solid-liquid separations for the copper salt solution to obtain a filtrate;
wherein, the two solid-liquid separations do not have sequence and include an adhesive separation and a co-precipitation separation;
the adhesive separation is a solid-liquid separation performed by adding a waste printed circuit board (PCB) powder and continuously stirring, wherein the waste PCB powder comprises epoxy resin;
the co-precipitation separation is a solid-liquid separation performed by adding tin chloride compound and continuously stirring, wherein the co-precipitation separation proceeds in a water bath of 60° C. to 90° C.;
(3) adding a second hydrochloric acid into the filtrate and adjusting pH to 0.1 to 2.5 and then performing evaporation concentration to a supersaturated solution, adding copper chloride seed crystal and then performing cooling crystallization and centrifugal separation to obtain an electronic-grade copper chloride dihydrate product.