10.0 wt% milk of lime was added to seawater containing AlCl3 at Mg/Al molar ratio of 3.0 until pH 10.5 with stirring, and kept at 25°C for 1 h. Hydrotalcite (HT) was precipitated as a single phase, and Mg2+ and Al3+ were quantitatively precipitated. The chemical composition was [Mg0.75Al0.25(OH)2][(SO4) 0.06(Cl)0.02(OH)0.11*]·0.27H 2O* (*Balance). A 100 mg-P/L Na2HPO4 solution and the HT were shaken at 25°C. Phosphate removal increased with increasing time and the HT quantity, and was the highest at pH 7-9. Phosphate ion could be quantitatively removed, adding 8 times the stoichiometric quantity of the HT at pH 8.7 for 6 h.
|ジャーナル||Phosphorus, Sulfur and Silicon and Related Elements|
|出版ステータス||Published - 2002|
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