REFINING METHOD FOR NICKEL SULFATE AQUEOUS SOLUTION

摘要

PROBLEM TO BE SOLVED: To provide a refining method for nickel sulfate aqueous solution that can stably remove impurities comprising light elements such as monovalent ions from a nickel sulfate aqueous solution while suppressing loss of nickel.SOLUTION: A nickel sulfate aqueous solution containing a plurality of impurity ions comprising monovalent cations and anions respectively by the content of 1 g/L or less is adjusted to and maintained at pH of 2.5 or lower, and the nickel sulfate aqueous solution is electrodialyzed in an electrodialysis process using a cation exchange film and an anion exchange film having monovalence selectivity.