US 12,403,427 B2
Method of separating and recovering cobalt salt and nickel salt
Tomoya Yoshizaki, Otsu (JP); Takanori Soya, Otsu (JP); Masakazu Koiwa, Otsu (JP); and Shigehisa Hanada, Otsu (JP)
Assigned to Toray Industries, Inc., Tokyo (JP)
Appl. No. 17/928,262
Filed by Toray Industries, Inc., Tokyo (JP)
PCT Filed May 28, 2021, PCT No. PCT/JP2021/020477
§ 371(c)(1), (2) Date Nov. 28, 2022,
PCT Pub. No. WO2021/241742, PCT Pub. Date Dec. 2, 2021.
Claims priority of application No. 2020-094338 (JP), filed on May 29, 2020.
Prior Publication US 2023/0219040 A1, Jul. 13, 2023
Int. Cl. B01D 61/02 (2006.01); B01D 61/04 (2006.01); B01D 69/02 (2006.01); B01D 69/10 (2006.01); B01D 69/12 (2006.01); B01D 71/56 (2006.01); C01G 51/10 (2006.01); C01G 53/10 (2006.01); C02F 1/44 (2023.01); C02F 1/66 (2023.01); C02F 9/00 (2023.01); C02F 101/20 (2006.01); C22B 3/00 (2006.01); C22B 3/06 (2006.01); C22B 3/22 (2006.01)
CPC B01D 61/0271 (2022.08) [B01D 61/025 (2013.01); B01D 61/029 (2022.08); B01D 61/04 (2013.01); B01D 69/02 (2013.01); B01D 69/10 (2013.01); B01D 69/12 (2013.01); B01D 71/56 (2013.01); C01G 51/10 (2013.01); C01G 53/10 (2013.01); C02F 9/00 (2013.01); C22B 3/06 (2013.01); C22B 3/22 (2013.01); C22B 23/0407 (2013.01); C22B 23/0453 (2013.01); B01D 2311/04 (2013.01); B01D 2311/06 (2013.01); B01D 2317/025 (2013.01); C02F 1/441 (2013.01); C02F 1/442 (2013.01); C02F 1/66 (2013.01); C02F 2101/20 (2013.01); C02F 2301/08 (2013.01)] 15 Claims
 
1. A method of separating and recovering a cobalt salt and a nickel salt, the method comprising a separation step of separating, by using a nanofiltration membrane, a cobalt salt and a nickel salt from a rare metal-containing aqueous solution containing at least both the cobalt salt and the nickel salt as rare metals,
wherein the nanofiltration membrane has a glucose permeability of 3 times or more a sucrose permeability, the sucrose permeability of 10% or less, and an isopropyl alcohol permeability of 50% or more when a 1,000 mg/L glucose aqueous solution, a 1,000 mg/L sucrose aqueous solution, and a 1,000 mg/L isopropyl alcohol aqueous solution, each having a pH of 6.5 and a temperature of 25° C., individually permeate through the nanofiltration membrane at an operating pressure of 0.5 MPa.