| 摘要 |
PURPOSE:To efficiently remove Ca and Mg ions in an aqueous alkali chloride soln. for electrolysis by adding fluorine ions to the soln. to form an insoluble precipitate and separating and removing the precipitate. CONSTITUTION:When Ca and Mg ions in an aqueous alkali chloride soln. for electrolysis are removed, fluorine ions are added to the soln. to form an insoluble precipitate, and this precipitate is separated and removed. The preffered source of fluorine ions is NaF, KF, HF or a mixture thereof. It is preferable that the soln. is adjusted to >=10pH, and the separation of the impurities is made more effective by adding a seed substance. The preffered seed substance is CaF2. |
