METHOD FOR PRODUCING NEW HYDROFLUORIC ACID TREATMENT LIQUID USING HYDROFLUORIC ACID TREATMENT WASTE LIQUID

摘要

To provide a method for producing a new hydrofluoric acid treatment liquid by using a hydrofluoric acid treatment waste liquid which has been conventionally disposed by neutralization or the like so as to effectively use resources and preserve the environment.SOLUTION: A production method comprises a solid matter removing step of adding a fluorinated alkali metal salt to a hydrofluoric acid treatment waste liquid containing hydrofluoric acid and fluorosilicic acid and then removing a solid matter of a metal fluorosilicate produced by the addition of the fluorinated alkali metal salt to recover a hydrofluoric acid-containing regenerated liquid from which the fluorosilicic acid has been removed or from which the fluorosilicic acid content is reduced; and a mixing step of mixing the hydrofluoric acid-containing regenerated liquid with hydrofluoric acid to obtain a new hydrofluoric acid treatment liquid using the hydrofluoric acid-containing regenerated liquid.SELECTED DRAWING: Figure 2