| abstract |
[PROBLEMS] Boron and / or fluorine capable of removing borofluoride or boron or fluorine contained in waste such as waste liquid without generating sludge and recovering high purity potassium borofluoride crystals Is provided. SOLUTION: The pH of water to be treated containing boron and fluorine is adjusted to 2 or less, and potassium borofluoride crystals precipitated by adding potassium are collected. Preferably, boron and / or fluorine is added so that fluorine is about 4 moles per mole of boron, and 1 mole or more of potassium is added per mole of boron. [Selection diagram] None |