| 摘要 |
<p>Disclosed is a method for collecting nickel from an acidic sulfuric acid solution that contains nickel and cobalt, as well as impurity elements such as iron, aluminum and manganese. The method is characterized by comprising the following steps (1)-(5). Step (1): Calcium carbonate is added into the acidic sulfuric acid solution, while blowing a mixed gas that is composed of a sulfur dioxide gas and air or an oxygen gas into the acidic sulfuric acid solution, so that the acidic sulfuric acid solution is subjected to oxidation/neutralization, and iron and aluminum are precipitated and removed. Step (2): Then, the solution is subjected to neutralization, so that a mixed hydroxide containing nickel and cobalt is precipitated, separated and collected. Step (3): The mixed hydroxide is dissolved in a sulfuric acid solution having a concentration of not less than 50% by mass, so that a concentrated solution of nickel and cobalt is obtained. Step (4): The concentrated solution is subjected to a solvent extraction process using a phosphate ester-based extraction agent, so that an extraction residue solution containing nickel is obtained. Step (5): The thus-obtained extraction residue solution is neutralized by adding a neutralizing agent thereto, so that nickel hydroxide produced thereby is separated and collected.</p> |
