Efficiency of aluminum-pillared montmorillonite on the removal of cesium and copper from aqueous solutions.
Efficiency of aluminum-pillared montmorillonite on the removal of cesium and copper from aqueous solutions.
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DOI：
10.1016/j.watres.2007.01.053
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发表时间：
2007-05
期刊：
影响因子：
12.8
通讯作者：
D. Karamanis;P. Assimakopoulos
中科院分区：
文献类型：
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作者：
D. Karamanis;P. Assimakopoulos
研究了铝柱撑层状蒙脱石（PILMs）对水溶液中铜、铯的吸附性能。通过改变初始条件，制备了几种PILMs，并通过X射线荧光（XRF），质子诱导γ射线发射（PIGE），X射线衍射（XRD）和吸附等温线进行了表征。用137 Cs作放射性示踪剂，用X射线荧光光谱法测定铜的吸附，用γ射线光谱法测定铯的吸附。的吸附动力学和能力的PILMs的关系，如初始金属浓度，溶液的初始pH值和竞争性阳离子的存在下的影响进行了测定。动力学研究表明，金属离子在PILMs上的吸附需要几分钟的平衡时间。一个伪一级方程被用来描述吸附过程中的铜或铯。去除铜和铯的最有效pH范围分别为4.0-6.0和3.0-8.0。铯的吸附等温线是最好的代表由两个网站的Langmuir模型，而铜的等温线遵循Freundlich或两个网站的Langmuir模型。用无机或有机竞争阳离子作为阻断剂的铯吸附实验表明，PILMs对铯的吸附的高选择性位点（占总吸附量的1-2%）除了层间交换位点外，还有表面和边缘位点。在铜的吸附，这两个网站被确定为层间网站的PILM后恢复其阳离子交换能力和网站与柱氧化物。
Aluminum-pillared-layered montmorillonites (PILMs) were tested for their potential application in the removal of copper or cesium from aqueous solutions. By varying the initial conditions, several PILMs were prepared and characterized by means of X-ray fluorescence (XRF), proton induced gamma-ray emission (PIGE), X-ray diffraction (XRD) and sorption isotherms. Uptake of metals was studied by means of XRF spectrometry for copper sorption or γ-ray spectrometry for cesium, using137Cs as radiotracer. The sorption kinetics and capacity of PILMs were determined in relation to the effects of factors such as the initial metal concentration, initial pH of the solution and the presence of competitive cations. Kinetic studies showed that an equilibrium time of few minutes was needed for the adsorption of metal ions on PILMs. A pseudo-first-order equation was used to describe the sorption process for either copper or cesium. The most effective pH range for the removal of copper and cesium was found to be 4.0–6.0 and 3.0–8.0, respectively. Cesium sorption isotherms were best represented by a two-site Langmuir model while copper isotherms followed the Freundlich or the two-site Langmuir model. Cesium sorption experiments with inorganic or organic competitive cations as blocking agents revealed that the high selective sites of PILMs for cesium sorption (1–2% of total) are surface and edge sites in addition to interlayer exchange sites. In copper sorption, the two sites were determined as interlayer sites of PILMs after restoring their cation exchange capacity and sites associated with the pillar oxides.