US 12,294,053 B2
Method for producing high-purity aqueous lithium salt solution
Keita Yamada, Koriyama (JP); Yukio Sakuma, Koriyama (JP); and Hiroto Inoue, Koriyama (JP)
Assigned to Asaka Riken Co., Ltd., Fukushima (JP)
Appl. No. 17/928,436
Filed by ASAKA RIKEN CO., LTD., Koriyama (JP)
PCT Filed Sep. 28, 2021, PCT No. PCT/JP2021/035688
§ 371(c)(1), (2) Date Nov. 29, 2022,
PCT Pub. No. WO2022/071335, PCT Pub. Date Apr. 7, 2022.
Claims priority of application No. 2020-167402 (JP), filed on Oct. 2, 2020.
Prior Publication US 2023/0145941 A1, May 11, 2023
Int. Cl. H01M 10/00 (2006.01); H01M 10/0563 (2010.01)
CPC H01M 10/0563 (2013.01) [H01M 2300/0002 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A method for producing an aqueous lithium salt solution, comprising:
a step of adjusting pH of a slurry, wherein the slurry contains a mixture of lithium phosphate and aluminum hydroxide obtained from a first aqueous lithium salt solution being a raw material and containing a lithium salt in a range of 0.1 to 70 g/L in terms of lithium, to a range of 2 to 3 to obtain a precipitate of aluminum phosphate;
a step of filtering off and removing the precipitate of aluminum phosphate from the slurry containing the mixture of lithium phosphate and aluminum hydroxide to obtain a second aqueous lithium salt solution; and
a step of purifying the second aqueous lithium salt solution to obtain the aqueous lithium salt solution by adjusting pH of the second aqueous lithium salt solution to a range of 7 to 10, and filtering off resulting precipitates of lithium phosphate and aluminum hydroxide.