| 摘要 |
PURPOSE:To efficiently change and control the valency of an aq. metal ion soln. by using a fluorine anion-exchange membrane having a specified structure produced by applying treatment with an acid or a base. CONSTITUTION:The valency of an aq. soln. of a metal ion capable of forming plural oxidation states is changed and controlled by anion-exchange membrane electrolysis. A membrane formed from a copolymer consisting of a repeating unit shown by the formula is treated with an acid or a base, and an anion- exchange group is introduced into the copolymer to obtain a fluorine carboxylic ester membrane which is used as the anion-exchange membrane in this case. In the formula, X is F or CF2, (l) is 0 or 1-5, (m) is 0 or 1, (n) is 1-5, p/q is 4-16, and R is an alkyl. Since the anion-exchange membrane has excellent durability and a metal ion is not leaked, the membrane is applicable to various processes, and the valency of the metal ion can be efficiently changed and controlled. |
