Fe(3+) coordinated to amino-functionalized MCM-41: an adsorbent for the toxic oxyanions with high capacity, resistibility to inhibiting anions, and reusability after a simple treatment.
Fe(3+) coordinated to amino-functionalized MCM-41: an adsorbent for the toxic oxyanions with high capacity, resistibility to inhibiting anions, and reusability after a simple treatment.
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DOI：
10.1016/j.jcis.2004.02.037
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发表时间：
2004-06
影响因子：
9.9
通讯作者：
T. Yokoi;T. Tatsumi;H. Yoshitake
中科院分区：
文献类型：
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作者：
T. Yokoi;T. Tatsumi;H. Yoshitake
Fe3+ 与固定在 MCM-41 介孔二氧化硅上的氨基配体配位，可作为有毒含氧阴离子的强吸附剂。砷酸盐、铬酸盐、硒酸盐和钼酸盐的最大吸附量分别为 1.56、0.99、0.81 和 1.29 mmolg−1。当氧阴离子的初始浓度小于 1 mmoll−1 时，它们被完全吸附去除，分配系数 Kd 大于 200,000。在吸附饱和时评估了自然界中发现的丰富的竞争性阴离子（NO3−、SO42−、PO43− 和 Cl−）对氧阴离子吸附的抑制作用。在这些阴离子中，PO43−存在时，氧阴离子的吸附受到最抑制，目标氧阴离子的选择性仍大于80%。除了从硫酸盐溶液中去除硒酸盐的情况外，其他共存的阴离子 NO3−、SO42− 和 Cl− 对含氧阴离子的吸附几乎没有影响。对目标氧阴离子的高能力和选择性归因于 Fe3+ 和氧阴离子之间的特定相互作用。酸处理和 Fe3+ 的重新配位导致所使用的吸附剂重新活化，其中获得了原始吸附容量的 87-90%，并且氧阴离子/Fe 化学计量没有改变。
Fe3+coordinated to amino ligands fixed on MCM-41 mesoporous silica works as a strong adsorbent for toxic oxyanions. The maximum adsorption amounts were 1.56, 0.99, 0.81, and 1.29 mmolg−1for arsenate, chromate, selenate, and molybdate, respectively. When the initial concentrations of oxyanions were less than 1 mmoll−1, they were removed completely by adsorption and the distribution coefficients Kdwere found to be more than 200,000. Inhibition of oxyanion adsorption by abundant competing anions found in nature, NO3−, SO42−, PO43−, and Cl−, was evaluated at adsorption saturation. Among these anions, the adsorption of the oxyanions was inhibited most in the presence of PO43−, with which the selectivities for the target oxyanions were still more than 80%. The other coexisting anions, NO3−, SO42−, and Cl−, had little influence on adsorption of the oxyanions except in the case of selenate removal from sulfate solution. The high ability and selectivity to the target oxyanions are attributed to specific interactions between Fe3+and the oxyanions. The acid treatment and re-coordination of Fe3+lead to a reactivation of the used adsorbent, in which 87–90% of the original adsorption capacity was obtained and the oxyanion/Fe stoichiometries were not changed.