US 12,421,133 B2
Preparation method for 2-4 micrometers battery-grade cobalt tetroxide
Kaihua Xu, Jiangsu (CN); Zhenkang Jiang, Jiangsu (CN); Aiqing Zhang, Jiangsu (CN); Bingzhong Li, Jiangsu (CN); Chao Wang, Jiangsu (CN); Dongwei Xu, Jiangsu (CN); Qiyong Shi, Jiangsu (CN); Fan Bi, Jiangsu (CN); and Chao Ning, Jiangsu (CN)
Assigned to GEM (Jiangsu) Cobalt Industry Co., Ltd., Taizhou (CN)
Filed by GEM (Jiangsu) Cobalt Industry Co., Ltd., Jiangsu (CN)
Filed on Jun. 17, 2022, as Appl. No. 17/842,817.
Application 17/842,817 is a continuation of application No. PCT/CN2019/126928, filed on Dec. 20, 2019.
Claims priority of application No. 201911319087.8 (CN), filed on Dec. 19, 2019.
Prior Publication US 2022/0315445 A1, Oct. 6, 2022
Int. Cl. C01G 51/04 (2025.01)
CPC C01G 51/04 (2013.01) [C01P 2004/03 (2013.01); C01P 2006/11 (2013.01); C01P 2006/12 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A preparation method for 2-4 μm battery-grade cobalt tetroxide, comprising:
step 1: obtaining a cobalt oxyhydroxide slurry by raw materials consisting of a cobalt salt solution, an alkaline solution, and pure water; wherein the obtaining a cobalt oxyhydroxide slurry by raw materials comprises: adding the cobalt salt solution with a cobalt ion concentration of 120-140 g/L and the alkaline solution with a concentration of 300-600 g/L by parallel flows at certain feed rates respectively to a reactor with the pure water as a base solution and an air flow, controlling a pH value of a reaction system in the reactor at 10-11 by adjusting a flow rate of the alkaline solution for a coprecipitation reaction at a certain stirring rate, decreasing the pH value of the reaction system by 0.1-0.2 per hour and increasing a flow rate of the cobalt salt solution by 15-25 L/h after reaction solutions begin to overflow until the pH value of the reaction system is decreased to 9.2-9.8 and the flow rate of the cobalt salt solution is increased to 320-360 L/h, continuously monitoring a particle size of cobalt oxyhydroxide, and stopping feeding of the cobalt salt solution and the alkaline solution when cobalt oxyhydroxide D50 reaches 2-4 μm, thus the cobalt oxyhydroxide slurry is obtained;
step 2: aging, washing, de-ironing and drying the cobalt oxyhydroxide slurry obtained in step 1 in sequence, thus obtaining dried cobalt oxyhydroxide; and
step 3: calcining the dried cobalt oxyhydroxide obtained in step 2 through a low temperature zone and a high temperature zone in sequence, thus obtaining 2-4 μm battery-grade cobalt tetroxide.