【摘 要】
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Groundwater contamination by various toxic substances is exposed and has become an important issue in water treatment.Particularly high-concentration arsenic pollution area are distributed in the Sout
【机 构】
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Department of Chemistry, College of Science and Technology, Nihon University,7-24-1 Narashinodai Fun
【出 处】
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The 14th International Congress on the Chemistry of Cement (
论文部分内容阅读
Groundwater contamination by various toxic substances is exposed and has become an important issue in water treatment.Particularly high-concentration arsenic pollution area are distributed in the South Asia, it has given great damage to the health of inhabitants.In conventional method, arsenic has been removed from contaminated water by mainly coagulating sedimentation using ferric chloride or aluminum salts.Arsenic is found in inorganic species such as forms arsenite (shown as As(Ⅲ)) and arsenate (shown as As(V)), and is mainly existed as oxyanions in aqueous solution.As(Ⅲ) is more difficult to remove from aqueous solution than As(V),therefore, oxidation as a pretreatment is necessary.It is well known that CrO42-oxyanion is immobilized into mono-sulfate type hydrate (AFm phase) by hydration of calcium aluminate (3CaO.Al2O3 shown as C3A).Arsenic oxyanions such as HAsO32-and HAsO42-are also expected to be immobilized into AFm phase analogous to the case of CrO42-by hydration of C3A.Also, it is thought that calcium aluminoferrite (6CaO.2Al2O3.Fe2O3, shown as C6A2F) is effectively usable as a decontaminating agent for arsenic because iron has a high affinity for inorganic arsenic species.In this study, aiming to the development of new applications of cement compounds such as C3A and C6A2F, removal behavior of arsenic from contaminated water was investigated.
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