PRODUCTION METHOD OF HIGH PURITY NICKEL SULFATE SOLUTION

摘要

PROBLEM TO BE SOLVED: To provide a production method of a high purity nickel sulfate solution capable of maximizing the distribution ratio to an organic phase of calcium, when exchanging the impurities and nickel by contacting with the organic phase containing nickel and the nickel sulfate solution containing impurities. SOLUTION: The nickel sulfate solution containing impurities such as calcium contacts with the mixed extractant of the acidic extractant containing nickel and the metal ion free acidic extractant. By controlling the mixing ratio (A+B)/A of the flow A of the acidic extractant containing nickel and the flow B of the metal ion free acidic extractant, the pH which reaches equilibrium when contacting, can be changed in the range between 6.0-4.0 without adding the pH preparation agent, especially the calcium can be removed most effectively in the range between pH 4.6-4.4.