The invention relates to a preparation method of
potassium fluoride. The method comprises: adding
fluorosilicic acid and
potassium fluosilicate into a reaction kettle, after starting to stir, continuously adding
potassium hydroxide solution, and regulating a pH (power of
hydrogen) value of
mixed solution in the reaction kettle into a first preset pH value; after completing the reaction, carrying out
solid-liquid separation, adding a first supernatant obtained by
solid-liquid separation into a refining kettle, then adding
sulfuric acid solution into the refining kettle and carrying out stirring; after continuously adding
barium hydroxide octahydrate into the refining kettle and carrying out stirring, transferring liquid obtained by
solid-liquid separation into a transfer groove, adding
potassium carbonate to carry out stirring, and after completing the reaction, transferring second supernatant into a concentration kettle; after regulating a pH value of mother solution of the
potassium fluoride in the concentration kettle by utilizing
hydrofluoric acid, carrying out spray-
drying on the mother solution of the
potassium fluoride to obtain
anhydrous potassium fluoride. According to thepreparation method of the potassium
fluoride, which is disclosed by the invention,
raw material cost and
machining cost can be reduced; the preparation method of the potassium
fluoride is beneficial to large-scale production application.