| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for mixing and kneading an iron salt or an aluminum salt and a water soluble resin, in which an iron salt or an aluminum salt which is rich in reactivity particularly with phosphoric acid ions among polyvalent metal salts and can solidify a phosphorous content is allowed to have controlled-releasability, and to provide a method for producing a solid phosphorous removal agent. SOLUTION: In the method for mixing and kneading an iron salt or an aluminum salt and a water soluble resin, before an iron salt or an aluminum salt and a water soluble resin are mixed kneaded, the water soluble resin is dissolved in water and an organic solvent, so as to obtain a water soluble resin solution, and the iron salt or aluminum salt and the water soluble resin solution are mixed and kneaded. The method for producing a solid phosphorous removal agent has the production process of: a stage (a) where a water soluble resin is dissolved in a mixed solvent of water and an organic solvent, so as to obtain a water soluble resin solution; a stage (b) where the water soluble resin solution obtained in the stage (a) is mixed and kneaded with the iron salt or aluminum salt; a stage (c) where the mixed and kneaded material obtained in the stage (b) is dried; a stage (d) where the dried material obtained in the stage (c) is pulverized; and a stage (e) where the pulverized material obtained in the stage (d) is subjected to compression molding. COPYRIGHT: (C)2007,JPO&INPIT
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