| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for producing a high purity active silicic acid aqueous solution containing metallic impurities in an extremely small content, for having high effectiveness to remove metallic impurities contained in an alkali silicate. <P>SOLUTION: The method for producing the high purity active silicic acid aqueous solution comprises obtaining an active silicic acid aqueous solution including a chelating agent containing nitrogen atom or phosphorous atom by mixing the chelating agent and an active silicic acid aqueous solution or mixing the chelating agent and an alkali silicate aqueous solution and then bringing the alkali silicate aqueous solution containing the chelating agent into contact with an H-type cation exchanger to obtain the active silicic acid aqueous solution containing the chelating agent, and bringing the active silicic acid aqueous solution including the chelating agent into contact with an anion exchanger. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
