| 摘要 |
PROBLEM TO BE SOLVED: To provide a continuous synthesis method where, though there is a problem that, for producing hydrotalcite, in the stage of nucleation, the use of a raw material solution with high concentration is advantageous, but, on the other hand, in the case the raw material with the high concentration is used, gel having a high viscosity is produced, and there is a possibility of causing the clogging in a continuous device, the two conflicting characteristics are considered, and to provide a device therefor. SOLUTION: Regarding a solution A with high concentration in which an aluminum source and a magnesium source are dissolved, and the molar ratio between aluminum ions and magnesium ions is prepared so as to be 1:2 to 1:5 and an alkaline solution B with high concentration, while their ratio is controlled by flow rates, the solution A is converted into a rotating flow through a rotating flow passage 4 and is fed to a stirring synthesis flow passage 5 continued to the flow passage 4, further, the solution B is directly fed to the synthesis passage 5, as fluidity capable of continuous driving is secured, reaction is completed in a time to suppress the growth of crystals in the synthesis flow passage 5, and, cleaning is performed so as to obtain a hydrotalcite compound of pH 7 to 9 having reduced deterioration, small crystallite sizes and high adsorbability. COPYRIGHT: (C)2007,JPO&INPIT
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