US 12,473,208 B2
Production method and production apparatus for nickel sulfate solution
Hitoshi Ishida, Niihama (JP)
Assigned to SUMITOMO METAL MINING CO., LTD., Tokyo (JP)
Appl. No. 17/413,748
Filed by SUMITOMO METAL MINING CO., LTD., Tokyo (JP)
PCT Filed Oct. 23, 2019, PCT No. PCT/JP2019/041545
§ 371(c)(1), (2) Date Jun. 14, 2021,
PCT Pub. No. WO2020/129396, PCT Pub. Date Jun. 25, 2020.
Claims priority of application No. 2018-237864 (JP), filed on Dec. 20, 2018.
Prior Publication US 2022/0055916 A1, Feb. 24, 2022
Int. Cl. C01G 53/10 (2006.01); C22B 3/00 (2006.01); C22B 3/08 (2006.01)
CPC C01G 53/10 (2013.01) [C22B 3/08 (2013.01); C22B 23/043 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A production method for a nickel sulfate solution, comprising:
a first dissolution step of introducing a nickel briquette, water, and sulfuric acid in an amount greater than that required to dissolve said nickel briquette to a leaching tank and dissolving the nickel briquette to obtain a primary nickel sulfate solution containing excess free sulfuric acid that was not involved in the leaching reaction,
a second dissolution step of introducing the primary nickel sulfate solution and additionally introducing a nickel briquette to a leaching adjustment tank and dissolving the additionally introduced nickel briquette with only free sulfuric acid in the primary nickel sulfate solution to obtain a nickel sulfate solution; to increase the nickel concentration, and to lower the free sulfuric acid concentration to obtain a nickel sulfate solution of a target concentration, the second dissolution step being performed after the first dissolution step,
measuring a nickel concentration and a pH of the nickel sulfate solution in the second dissolution step, and controlling supply amounts of the sulfuric acid and the water in the first dissolution step based on the measured nickel concentration and the pH.