| 摘要 |
PROBLEM TO BE SOLVED: To provide a fluorine remover capable of removing fluorine in a solution to the environmental standard value of 0.8 mg/l or under. SOLUTION: The fluorine remover comprises composite particles as an active constituent containing calcium carbonate and hydroxylapatite produced by mixing phosphoric acid in a mid course of a carbonation process of an ordinary industrial calcium carbonate production process by a carbon dioxide gas combination method. The composite particles are preferably produced by mixing phosphorous acid while carbon dioxide gas is introduced or after the introduction of carbon dioxide is stopped at the time when 50-80% of the predetermined completion time of the carbonation has been run on wherein a pH of the suspension becomes 7 to 8. COPYRIGHT: (C)2006,JPO&NCIPI
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