National Research Center, Water Pollution Control Department, Ekbehouth Street 33, Dokki, Cairo 12311, Egypt.
J Hazard Mater. 2010 Oct 15;182(1-3):842-7. doi: 10.1016/j.jhazmat.2010.06.118. Epub 2010 Jul 23.
In this study, the adsorption behavior of zeolites A and X, which are prepared from very cheap local Egyptian clay (kaolin), with respect to Cu(2+), Cd(+2), Cr(+2), Ni(+2) and Zn(2+) has been studied. The batch method has been employed, using metal solutions ranging from 100 to 400 mg/L. The distribution coefficients (K(d)) and adsorption percent were determined for the adsorption system as a function of sorbate concentration. In the uptake evaluation part of the study, adsorption ratios of metal cations on zeolites A and X match to Langmuir, Freundlich, and Dubinin-Kaganer-Radushkevich (DKR) adsorption isotherm data. Also, every cation exchange capacity for metals has been calculated. According to the equilibrium studies, the selectivity sequence can be given as Pb(2+)>Cd(2+)>Cu(2+)>Zn(2+)>Ni(2+). It was found that the uptake depend on hydrated ion diameter. This study may attract more interest due to the presence of large reservoirs of very cheap kaolin in Egypt from which both zeolite types were prepared.
本研究考察了由非常廉价的埃及本地黏土（高岭土）制备的沸石 A 和 X 对 Cu(2+)、Cd(+2)、Cr(+2)、Ni(+2)和 Zn(2+)的吸附行为。采用批处理法，使用浓度范围为 100-400mg/L 的金属溶液。作为吸附体系的函数，测定了分配系数（K(d)）和吸附百分比。在研究的吸附评估部分，金属阳离子在沸石 A 和 X 上的吸附比与朗缪尔、弗雷德里希和杜宾宁-卡加涅尔-拉杜什凯维奇（DKR）吸附等温线数据相匹配。此外，还计算了每种金属的阳离子交换容量。根据平衡研究，可给出选择性顺序为 Pb(2+)>Cd(2+)>Cu(2+)>Zn(2+)>Ni(2+)。结果表明，吸取决于水合离子的直径。由于埃及存在大量非常廉价的高岭土，这两种沸石都可以从高岭土中制备，因此本研究可能会引起更多的关注。
