Lead(II) immobilization in kaolinite at near-neutral pH conditions using titanium-based compounds
Lead(II) immobilization in kaolinite at near-neutral pH conditions using titanium-based compounds
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DOI：
10.1016/j.jece.2017.06.002
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发表时间：
2017-08
影响因子：
7.7
通讯作者：
Tasuma Suzuki;Satoshi Kakoyama;T. Nomura;C. Fukuoka;Masakazu Niinae
中科院分区：
文献类型：
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作者：
Tasuma Suzuki;Satoshi Kakoyama;T. Nomura;C. Fukuoka;Masakazu Niinae
选择锐钛矿和层状质子化钛酸盐（LPT）作为潜在的Pb（II）的固定化剂的一系列批次吸附/解吸和固定化实验。批吸附实验表明，吸附Pb（II）到Al 2 O3和LPT都有利于在较高的pH值，和LPT表现出显着更高的Pb（II）吸附能力比Al 2 O3和两个市售的钛基吸附剂。此外，铅（II）吸附诱导的LPT层结构的结构变形，这导致不可逆吸附;这一趋势没有观察到的Pb 2+。基于这些良好的LPT吸附/解吸特性作为Pb（II）固定剂，铅（II）的人工污染高岭石固定使用LPT。浸出试验结果表明，LPT有效地固定Pb（II）低于日本允许的水平（0.01 mg/L）。在75毫克/4克高岭土或以上的剂量，这种LPT的固定能力，即使保持在浸出液的pH值为2.5，相当于200年的土壤暴露于酸雨。这些实验数据表明，LPT是一种有效的Pb（II）固定剂，可以在近中性pH条件下固定Pb（II），并且其有效性持续较长时间。
Anatase and layered protonated titanate (LPT) were chosen as potential Pb(II) immobilization agents for a series of batch adsorption/desorption and immobilization experiments. Batch adsorption experiments demonstrated that adsorption of Pb(II) onto anatase and LPT were both favored at higher pH, and LPT exhibited significantly higher Pb(II) adsorption capability than anatase and the two commercially available Ti-based adsorbents. In addition, Pb(II) adsorption induces structural deformation of the LPT layer structure, which results in irreversible adsorption; this trend was not observed for anatase. Based on these favorable LPT adsorption/desorption characteristics as a Pb(II) immobilization agent, Pb(II) in artificially contaminated kaolinite was immobilized using LPT. Leaching test results demonstrated that LPT effectively immobilized Pb(II) below the permissible level in Japan (0.01 mg/L). At the dosage of 75 mg/4 g-kaolinite or above, this LPT immobilization capacity was maintained even when the leaching solution pH was 2.5, equivalent to 200 years of soil exposure to acid rain. These experimental data demonstrated that LPT is an effective Pb(II) immobilization agent that can immobilize Pb(II) at near-neutral pH conditions, and its effectiveness lasts for a long time.