中文摘要：

铅、铜、镉是3种具有代表性的重金属污染物，可用于模拟多重离子复合污染情况。研究了离子浓度、土水比等因素对3种元素在黄土上二元竞争吸附特性的影响。等温吸附模型Langmuir、Freundlich和D-R模型都能在一定程度上解释Pb（Ⅱ）-cu（n）、Pb（11）-Cd（Ⅱ）、Cu（Ⅱ）-Cd（Ⅱ）在黄土上的竞争吸附性能。黄土对Pb（Ⅱ）、Cu（Ⅱ）、Cd（Ⅱ）的选择顺序为Pb（Ⅱ）〉Cu（Ⅱ）〉Cd（Ⅱ）。相比单一吸附，黄土对每种离子的吸附容量均有不同程度的下降。溶液的初始浓度越大，3种离子在单位黄土上的最大吸附量也随之增大，吸附效率随之降低；适当增大土水比可提高离子的去除效率。试验结果为黄土作为防污屏障和污水处理材料提供了依据。

英文摘要：

Lead, copper, cadmium is three kinds of typical heavy metal contaminants which can be used to simulate the solution of composite contaminate. The factors including the concentration and soil-water ratio are studied to investigate the competitive adsorption behaviors of loess towards Pb（Ⅱ）, Cu（Ⅱ） and Cd（Ⅱ）. The adsorption test results can be interpreted by three isotherm models （i.e., Langmuir, Freundlich and D-R models） to certain extent. The preference ranking of loess to three heavy metal ions is Pb（Ⅱ）〉Cu（Ⅱ）〉Cd（Ⅱ）. Compared with those of single adsorption, the adsorption capacities of the competitive ions on loess decrease to some extent. Higher initial concentration of heavy metal ions leads to larger optimum adsorption amount of loess, and the adsorption removal efficiency decreases at the same time. The removal efficiency of three heavy metal ions from aqueous solution can be increased by increasing the solid-liquid ratio. The results may provide an evidence for loess as the containment barrier system as well as the adsorbent removing heavy metal containment in aquatic environment.