US 12,258,282 B2
Method for producing nickel sulfate solution for secondary battery from nickel cathode
Heon Sik Choi, Ulsan (KR); Jae Hoon Joo, Ulsan (KR); and Tae Kyung Lee, Seoul (KR)
Assigned to KOREA ZINC CO., LTD., Seoul (KR); and KEMCO, Seoul (KR)
Filed by KOREA ZINC CO., LTD., Seoul (KR); and KEMCO, Seoul (KR)
Filed on Sep. 22, 2023, as Appl. No. 18/472,603.
Application 18/472,603 is a continuation of application No. PCT/KR2023/004406, filed on Mar. 31, 2023.
Claims priority of application No. 10-2023-0004092 (KR), filed on Jan. 11, 2023.
Prior Publication US 2024/0228321 A1, Jul. 11, 2024
Int. Cl. C01G 53/10 (2006.01); B09B 3/80 (2022.01); C22B 3/00 (2006.01); H01M 4/58 (2010.01); H01M 10/54 (2006.01); B09B 101/16 (2022.01); H01M 4/02 (2006.01)
CPC C01G 53/10 (2013.01) [B09B 3/80 (2022.01); C22B 23/043 (2013.01); H01M 4/5815 (2013.01); H01M 10/54 (2013.01); B09B 2101/16 (2022.01); C01P 2006/40 (2013.01); H01M 2004/028 (2013.01)] 1 Claim
OG exemplary drawing
 
1. A method for producing a nickel sulfate solution, comprising:
leaching a nickel cathode in sulfuric acid under a temperature of 170° C. to 200° C. and a pressure of 8.5 bar to 16 bar while introducing at least one of oxygen gas and nitrogen gas to produce a leachate;
neutralizing the leachate produced in the leaching step by adding nickel powder to produce a neutralized solution with a pH 5.0 to 7.0;
filtering the neutralized solution produced in the neutralizing to produce a filtrate and a cake that includes undissolved nickel; and
adding the cake to the neutralizing,
wherein a nickel concentration in the neutralized solution after the neutralizing is 120 to 140 g/L wherein the nickel cathode concentration in the leaching step is 2 equivalents of the nickel concentration in the neutralized solution after the neutralizing; and wherein the sulfuric acid concentration in the leaching step is 1 equivalent of the nickel concentration in the neutralized solution after the neutralizing.