Adsorption of thorium(IV) on magnetic multi-walled carbon nanotubes
Adsorption of thorium(IV) on magnetic multi-walled carbon nanotubes
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DOI：
10.1007/s11426-014-5204-x
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发表时间：
2014-11-01
影响因子：
9.6
通讯作者：
Wu WangSuo
中科院分区：
文献类型：
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作者：
Liu Peng;Qi Wei;Wu WangSuo
采用间歇法研究了pH、接触时间、固液比、温度和C-60(C(COOH)(2)) (n)对磁性多壁碳纳米管（MMWCNTs）吸附Th（IV）的影响。动力学过程表明，Th（IV）在MMWCNTs上的吸附在40 h内达到平衡，符合准二级动力学模型。Th（IV）在MMWCNTs上的吸附显著依赖于pH值，在pH 3.0 ~ 5.0时吸附比显著增加，然后随着pH值的增加保持稳定状态。在低pH下，不同的C-60(C(COOH)(2)) (n)含量可以提高Th（IV）在MMWCNTs上的吸附量，而在高pH下则会抑制Th（IV）在MMWCNTs上的吸附量。通过Langmuir、Freundlich和Dubini-Radushkevich模型模拟吸附等温线可以看出，Th（IV）在MMWCNTs上的吸附模式分别以表面络合为主，吸附过程为吸热不可逆过程。
The influences of pH, contact time, solid-liquid ratio, temperature and C-60(C(COOH)(2)) (n) on Th(IV) adsorption onto the magnetic multi-walled carbon nanotubes (MMWCNTs) were studied by batch technique. The dynamic process showed that the adsorption of Th(IV) onto MMWCNTs could reach equilibrium in 40 h and matched the pseudo-second-order kinetics model. The adsorption of Th(IV) onto MMWCNTs was significantly dependent on pH values, the adsorption ratio increased markedly at pH 3.0-5.0, and then maintained a steady state as pH values increased. At low pH, different C-60(C(COOH)(2)) (n) content could enhance the adsorption content of Th(IV) onto MMWCNTs, but restrained it at higher pH. Through simulating the adsorption isotherms by Langmuir, Freundlich and Dubini-Radushkevich models, it could be seen respectively that the adsorption pattern of Th(IV) onto MMWCNTs was mainly surface complexation, and that the adsorption process was endothermic and irreversible.