利用等温吸附法考察了高炉水淬渣对Cu2+、Cd2+、Zn2+的单组分吸附和竞争吸附性能。结果表明，单一组分吸附时，金属离子吸附等温线属于“H”形等温线，吸附平衡符合 Langmuir 吸附等温模型，高炉水淬渣吸附的顺序为Cu2+﹥Cd2+﹥Zn2+，这与重金属离子电负性、水合离子半径及荷径比等有关。当加入竞争离子后，Cu2+的吸附等温线基本维持原来形状，且仍旧与 Langmuir 吸附等温模型比较相符，而 Cd2+和 Zn2+的吸附无法与现有等温吸附模型很好地拟合，等温线的形状由于竞争作用也与传统的等温线均不相同，同时各金属离子的吸附量都比单组分的吸附量降低了。吸附动力学过程先是一个快速阶段，然后进入慢速阶段。无论是单组分还是竞争条件下，伪二级动力学方程拟合结果较好，说明高炉水淬渣与Cu2+、Cd2+、Zn2+之间的吸附过程主要是以化学吸附为主。%The single-component and competitive adsorption properties of Cu2+、Cd2+、Zn2+ ions on water-quenched blast furnace slag (WBFS) were investigated by isothermal adsorption experiment. The results showed the adsorption process and isotherm curves of the metal ions followed Langmuir isotherm model and “H” type in single-component adsorption,respectively. The order of the adsorption capacities was Cu2+﹥Cd2+﹥Zn2+,which determined mainly by the electro negativity,hydrated ionic radius and charge to radius ratio. The adsorption isotherms of Cu2+ maintained the original shape and still fitted to Langmuir adsorption model in competitive condition,while the other adsorption model could not well represent the competitive adsorption of Cd2+and Zn2+. The mutual competition and antagonism effect of heavy metals in competitive system resulted in the irregularity of sorption isotherm curves of Cd2+and Zn2+. The adsorption capacities of the competitive ions on WBFS decreased to some extent compared with those of single ion adsorption. The sorption kinetic processes were rapid first and followed slow in accordance with pseudo-second-order kinetic model,which suggested that the process controlling the rate may be a chemical sorption between WBFS and Cu2+、Cd2+、Zn2+.
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