SEPARATION AND RECOVERY METHOD OF METAL ION

摘要

PROBLEM TO BE SOLVED: To provide an efficient separation and recovery method of a metal such as rare earths and the like by using the formation reaction of a hydrophobic ionic liquid as an extraction medium.SOLUTION: An ionic liquid phase is formed in an aqueous solution by separately dissolving a cation substance and an anion substance and reacting in an aqueous solution dissolved with a metal ion and at least one kind of metal ions in the aqueous solution is extracted in the ionic liquid phase. At that time, a desired metal ion can be selectively separated and recovered by adjusting the pH of the aqueous solution dissolved with the metal ion or a pH buffer solution to be added.