Laboratoire Eau, Energie et Environnement (LR3E), code: AD-10-02, Ecole Nationale d'Ingénieurs de Sfax, département de matériaux, Université de Sfax, B.P1173.W.3038, Sfax-Tunisie.
J Hazard Mater. 2010 Jun 15;178(1-3):753-7. doi: 10.1016/j.jhazmat.2010.02.004. Epub 2010 Feb 6.
The adsorption of Pb(2+) ions onto Tunisian clay in aqueous solution was studied in a batch system. Four samples of clay (RGC, RRC, AGC, and ARC) were used. The raw RGC and RRC clays were sampled in jebel Tejera-Esghira in Medenine area (Southeast of Tunisia). AGC and ARC corresponds respectively to RGC and RRC activated by 6M sulphuric acid. The adsorbents employed were characterized by X-Ray Diffraction, chemical analysis, and the specific surface area was also estimated. The ability of clay samples to remove Pb(2+) ions from aqueous solutions has been studied at different operating conditions: temperature and pH. The optimum pH for lead ions retention was found 7.0 for the four clay samples. The effect of temperature on adsorption phenomenon was also investigated. The results indicated that adsorption is an exothermic process for lead ions removal. The equilibrium adsorption data were analysed using the Langmuir and Freundlich isotherms. The adsorption capacities (X(m)) for RRC, RGC, ARC and AGC were found 17.84, 25.44, 27.15 and 40.75 mg g(-1), respectively. The performance of the red clay after activation was compared to that of silica gel, which has maximum adsorption of 20 mg g(-1). On the other hand, although the performance of activated carbon (88.3 mg g(-1)) is by far higher than that of the green clay after activation, the latter seems to have better performance than that of the silica gel.
在批处理系统中研究了 Pb(2+)离子在水溶液中被突尼斯粘土吸附的情况。使用了四种粘土样品（RGC、RRC、AGC 和 ARC）。原始的 RGC 和 RRC 粘土是在 Medenine 地区的杰贝勒-特杰拉-埃斯赫拉（突尼斯东南部）采集的。AGC 和 ARC 分别对应于用 6M 硫酸活化的 RGC 和 RRC。所使用的吸附剂通过 X 射线衍射、化学分析进行了表征，并估算了比表面积。研究了不同操作条件（温度和 pH）下粘土样品去除水溶液中 Pb(2+)离子的能力。四种粘土样品的最佳 pH 值为 7.0。还研究了温度对吸附现象的影响。结果表明，吸附是去除铅离子的放热过程。使用 Langmuir 和 Freundlich 等温线分析了吸附平衡数据。发现 RRC、RGC、ARC 和 AGC 的最大吸附量（X(m)）分别为 17.84、25.44、27.15 和 40.75 mg g(-1)。与硅胶相比，活化后的红土的性能被比较，硅胶的最大吸附量为 20 mg g(-1)。另一方面，尽管活性炭（88.3 mg g(-1)）的性能远高于活化后的绿土，但后者的性能似乎优于硅胶。
