| 摘要 |
<p>In a solvent extraction step, using an organic solvent 134 as an extraction solvent, nickel and cobalt contained in a neutralization solution 113 are separated into a nickel sulfate solution 130 and a cobalt sulfate solution 132, which are then fed to a nickel recovery step and a cobalt recovery step, respectively. Here, by using an organic solvent having a monothiophosphinic acid group as an organic solvent 134, a cobalt sulfate solution 132 substantially free from magnesium, manganese and calcium can be obtained.</p> |
