Department of Soil, Plant, Environment and Animal Production Science, Faculty of Agriculture, University of Naples "Federico II", Via University 100, 80055 Portici (Naples), Italy.
Chemosphere. 2011 Jul;84(4):484-9. doi: 10.1016/j.chemosphere.2011.03.020. Epub 2011 Apr 8.
The competitive sorption among Cu, Pb and Cr in ternary system on Na-montmorillonite at pH 3.5, 4.5 and 5.5 and at different heavy metal concentrations, and the effect of varying concentrations of Al, Fe, Ca and Mg on the sorption of heavy metals were studied. Competitive sorption of Cu, Pb and Cr in ternary system on montmorillonite followed the sequence of Cr≫Cu>Pb. Moreover, the competition was weakened by the increase of pH while was intensified by the increase of heavy metal concentration. The sorption of heavy metal on montmorillonite was inhibited by the presence of Ca and Mg, while Al and Fe showed different patterns in affecting heavy metal sorption. Aluminum and Fe generally inhibited the sorption of heavy metal when the pH and/or concentration of major elements were relatively low. However, promoting effects on heavy metal sorption by Al and Fe were found at relatively high pH and/or great concentration of major elements. The inhibition of major elements on heavy metal sorption generally followed the order of Al>Fe>Ca⩾Mg, while Fe was more efficient than Al in promoting the sorption of heavy metals. These findings are of fundamental significance for evaluating the mobility of heavy metals in polluted environments.
在 pH 值为 3.5、4.5 和 5.5 以及不同重金属浓度下，研究了三元体系中铜、铅和铬在钠蒙脱石上的竞争吸附，以及不同浓度的 Al、Fe、Ca 和 Mg 对重金属吸附的影响。在蒙脱石上，三元体系中 Cu、Pb 和 Cr 的竞争吸附遵循 Cr≫Cu>Pb 的顺序。此外，随着 pH 值的升高，竞争作用减弱，而随着重金属浓度的升高，竞争作用增强。Ca 和 Mg 的存在抑制了重金属在蒙脱石上的吸附，而 Al 和 Fe 对重金属吸附的影响则表现出不同的模式。当主要元素的 pH 值和/或浓度相对较低时，Al 和 Fe 通常会抑制重金属的吸附。然而，在较高的 pH 值和/或主要元素的浓度下，发现 Al 和 Fe 对重金属吸附有促进作用。主要元素对重金属吸附的抑制作用一般遵循 Al>Fe>Ca ⩾Mg 的顺序，而 Fe 在促进重金属吸附方面比 Al 更有效。这些发现对于评估污染环境中重金属的迁移性具有重要意义。
