| 蒙脱石-OR-SH复合体材料对土壤镉的钝化及机制 |
| 摘要点击 2333 全文点击 1206 投稿时间：2014-10-21 修订日期：2015-01-25 |
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| 中文关键词 蒙脱石-OR-SH复合体 土壤 钝化 镉 机制 |
| 英文关键词 smectite-OR-SH compound soil inactivate cadmium mechanism |
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| 中文摘要 |
| 通过吸附解吸实验、盆栽实验及材料的表征测试分析,探讨了蒙脱石-OR-SH复合体对土壤中Cd的钝化效果和机制. 结果表明,蒙脱石改性后对镉的饱和吸附容量明显提高; 蒙脱石-OR-SH复合体对Cd2+的吸附很稳定,不易解吸; 在原土、Cd 3 mg·kg-1和Cd 10 mg·kg-1污染土上,添加蒙脱石-OR-SH复合体能够不同程度地提高作物产量,小白菜Cd含量分别比对照降低61.00%、62.10%和83.73%. 表征测试显示,Cd成功地吸附到了复合体上,并与巯基发生了配位反应,复合体表面的絮状物增多. 蒙脱石-OR-SH复合体与镉的反应机制除了静电吸附、离子交换吸附和羟基配位吸附外,主要存在巯基配位吸附. |
| 英文摘要 |
| Adsorption and desorption experiments, pot experiments and characterization test were performed to investigate the immobilization effect and mechanism of the smectite-OR-SH compound for reducing cadmium uptake by plants in contaminated soils. The results showed that the saturated adsorption capacity for the adsorption of Cd2+ on smectite raised distinctly after functionalized. The adsorption of Cd2+ on smectite-OR-SH compound was very stable and it was difficult for Cd2+ to be desorbed from it.Crop yields promoted differently in original soil, Cd 3 mg·kg-1 soil and Cd 10 mg·kg-1 soil after adding the smectite-OR-SH compound. And the cadmium content of the cabbage reduced 61.00%, 62.10% and 83.73% respectively compare with the control. Characterization test analysis showed that Cd was adsorbed by the compound successfully and ligand interaction occurred between Cd and the thiol group. Floc amount on the compound surface increased correspondingly. In addition to electrostatic adsorption, ion exchange and hydroxyl ligand adsorption, the reaction mechanism of smectite-OR-SH compound with Cd was mainly sulfhydryl ligand adsorption. |
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