Fluorine insolubilizers and methods of producing same
AssigneeChiyoda Ute Co., Ltd.
InventorsMasamoto Tafu, Tetsuji Chohji, Takeshi Toshima, Takumi Fujita, Hirokazu Nakano, Ichiro Morioka, Katsumi Mori, Makoto Maeda, Kazumasa Takenaka
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Abstract
A fluorine insolubilizer capable of sufficiently insolubilizing fluorine within a short time contains calcium hydrogen phosphate dihydrate in an amount of 95-40 mass % and hydroxy or hydroxyl apatite in an amount of 5-60 mass % for a total of 100 mass %.
Claims15
A fluorine insolubilizer comprising calcium hydrogen phosphate dihydrate in an amount of 95-40 mass % and hydroxy or hydroxyl apatite in an amount of 5-60 mass % for a total of 100 mass %, wherein the hydroxyl apatite is non-crystalline.
A method of producing fluorine insolubilizer, said method comprising the steps of:
- causing a reaction by adding an aqueous solution of phosphoric acid gradually over 5 minutes or more to an aqueous dispersion of hydrated lime while stirring such that the phosphoric acid and the hydrated lime will have a molar ratio of 1/1-1/1.5;
- and
- separating from reaction system of said reaction a solid component that contains calcium hydrogen phosphate dihydrate in an amount of 95-40 mass % and hydroxyl apatite in an amount of 5-60 mass % for a total of 100 mass %.
Dependencies are inferred from the claim text.