针铁矿对重金属Pb^2＋、Cd^2＋的吸附特征

本文采用平衡振荡法，主要探讨了重金属铅和镉在针铁矿上的环境行为。研究结果表明针铁矿对重金属有较强的吸附作用。在pH一定时，针铁矿对Pb^2＋和Cd^2＋的吸附率随着初始浓度的增加而增大。随着介质pH升高，针铁矿对Pb^2＋和Cd^2＋的吸附量与吸附率均增大，最大吸附率可达到99．71％和99．46％，而解吸量则随之降低。在高pH条件下，针铁矿对Pb^2＋和Cd^2＋的结合牢固，且与Pb^2＋的稳定度大于Cd^2＋。研究表明，环境中针铁矿对铅、镉等重金属的环境化学行为具有重要的影响。利用针铁矿处理含Pb^2＋和Cd^2＋的污水具有良好的应用潜力。

Adsorption of Heavy Metal Ions Pb2+ and Cd2+ on Goethite

In this paper an experiment was conducted adopting balance vibration method to study the environmental behavior of Pb^2＋ and Cd^2＋ on goethite. The results showed that goethite had strong adsorption of Pb^2＋ and Cd^2＋. At certain pH, the higher the initial concentration of Pb^2＋ or Cd^2＋ was, the higher the adsorbed amount on goethite was. When the pH value increased, both the amount and rate of adsorption increased up to 99.71% and 99. 46% respectively, while their amount of desorption decreased. At high pH, the combinations of Pb^2＋ and Cd^2＋ on goethite were strong, and the combination of Pb^2＋ on goethite was more stable than Cd^2＋ . Research showed that goethite could have an important effect on the environmental behavior of heavy metal ions such as Pb^2＋ and Cd^2＋. Thus it had a good potential application to remove heavy metal ions in waste water containing Pb^2＋ and Cd^2＋ using goethite.