Department of Chemical and Biomolecular Engineering (BK21 program), KAIST, 335 Gwahak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
J Hazard Mater. 2011 Nov 30;196:101-8. doi: 10.1016/j.jhazmat.2011.08.077. Epub 2011 Sep 6.
We demonstrated that water-soluble aminopropyl magnesium functionalized phyllosilicate could be used as a soil-flushing agent for heavy metal contaminated soils. Soil flushing has been an attractive means to remediate heavy metal contamination because it is less disruptive to the soil environment after the treatment was performed. However, development of efficient and non-toxic soil-flushing agents is still required. We have synthesized aminoclays with three different central metal ions such as magnesium, aluminum, and ferric ions and investigated applicability of aminoclays as soil flushing agents. Among them, magnesium (Mg)-centered aminoclay showed the smallest size distribution and superior water solubility, up to 100mg/mL. Mg aminoclay exhibited cadmium and lead binding capacity of 26.50 and 91.31 mg/g of Mg clay, respectively, at near neutral pH, but it showed negligible binding affinity to metals in acidic conditions. For soil flushing with Mg clay at neutral pH showed cadmium and lead were efficiently extracted from soils by Mg clay, suggesting strong binding ability of Mg clay with cadmium and lead. As the organic matter and clay compositions increased in the soil, the removal efficiency by Mg clay decreased and the operation time increased.
我们证明了水溶性氨丙基镁功能化层状硅酸盐可用作重金属污染土壤的土壤冲洗剂。土壤冲洗是一种很有吸引力的重金属污染修复方法，因为在处理后对土壤环境的破坏较小。然而，仍然需要开发高效、无毒的土壤冲洗剂。我们已经合成了三种不同中心金属离子的氨粘土，如镁、铝和铁离子，并研究了氨粘土作为土壤冲洗剂的适用性。其中，镁（Mg）中心的氨粘土表现出最小的粒径分布和优异的水溶性，最高可达 100mg/mL。在接近中性 pH 值的条件下，Mg 氨粘土对镉和铅的结合能力分别为 26.50 和 91.31mg/g 的 Mg 粘土，但在酸性条件下对金属的结合亲和力可忽略不计。在中性 pH 值下用 Mg 粘土进行土壤冲洗，表明 Mg 粘土能有效地从土壤中提取镉和铅，表明 Mg 粘土与镉和铅具有很强的结合能力。随着土壤中有机质和粘土成分的增加，Mg 粘土的去除效率降低，操作时间延长。
