天然沸石对重金属离子的竞争性吸附研究

Effect of zeolite on competitive adsorption of heavy metals ions

通过室内分析的方法研究了天然沸石对4种重金属离子Cd2+、Zn2+、Cu2+、Pb2+的竞争性吸附特性。研究结果表明,与单一离子体系比较,沸石在竞争体系中对Cd2+、Zn2+、Cu2+、Pb2+4种重金属离子的吸附量均呈下降的趋势。竞争体系下,其它重金属离子的存在显著地抑制了沸石对Cd2+的吸附,而对Pb2+的吸附几乎没有影响。天然沸石对4种重金属离子的富集系数,其大小顺序依次为Pb2+>Cu2+>Zn2+>Cd2+。该选择性吸附顺序可能与重金属离子的水合能、离子半径、有效水合离子半径等因素密切相关。

Tiffs paper studied the influence of natural zeolite on the competitive adsorption characteristic of lead, copper, cadmium, and zinc ions. The result showed that the adsorption capacity of lead, copper, cadmium, and zinc ions on zeolite were decreased in competitive system compared with that in single system. Adsorption of lead ions by zeolite decreased marginally in competitive adsorption condition, whereas a significant decrease was observed on the adsorption of cadmium ions by zeolite at the presence of lead, copper and zinc ions. The enrichment coefficient of Cd^2＋、Zn^2＋、Cu^2＋ and Pb^2＋ ion by natural zeolite was as the follow Pb^2＋〉Cu^2＋〉Zn^2＋〉Cd^2＋ , this order maybe relative to the radius, valid radius and hydration beat of heavy metal ions.