Equilibrium and kinetics of metal ion adsorption onto a commercial H-type granular activated carbon: experimental and modeling studies.
Equilibrium and kinetics of metal ion adsorption onto a commercial H-type granular activated carbon: experimental and modeling studies.
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DOI：
10.1016/s0043-1354(00)00521-2
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发表时间：
2001-07
期刊：
影响因子：
12.8
通讯作者：
J. Chen;M. Lin
中科院分区：
文献类型：
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作者：
J. Chen;M. Lin
对商用H型颗粒活性炭的金属离子吸附平衡和动力学进行了系统研究。碳的滴定表明表面电荷密度随着pH值的增加而降低。随着溶液 pH 值和离子强度的增加，获得了更高的铜吸附量。金属去除率由高到低的顺序为：Cu2+>Zn2+≈Co2+。添加锌或钴不会影响铜的去除，而铜会降低锌和钴的去除。动力学实验表明，铜吸附在前30-60min内迅速发生，并在3-5h内达到完全去除。锌和钴的去除比铜的去除稍慢。发现传质对于金属吸附速率很重要。表面络合物形成模型成功地用于描述表面变化密度以及单种和多种金属吸附平衡。铜的去除是由于 Cu2+、CuOH+ 和 CuCl+ 的吸附，而锌和钴的吸收是由于 SOM2+ 和 SOMOH+（M=Zn 和 Co）的表面金属络合物的形成。结果发现，扩散控制模型很好地描述了各种金属离子和 pH 值的吸附动力学。最后对动力学模型参数进行了敏感性分析。
Systematic studies on metal ion adsorption equilibrium and kinetics by a commercial H-type granular activated carbon were carried out. Titration of the carbon showed that the surface charge density decreased with an increasing pH. Higher copper adsorption was obtained with increasing solution pH and ionic strength. Metal removal was in the descending order: Cu2+>Zn2+≈Co2+. Copper removal was not affected by addition of zinc or cobalt, while copper can reduce both zinc and cobalt removal. Kinetic experiments demonstrated that the copper adsorption rapidly occurred in the first 30–60min and reached the complete removal in 3–5h. Removal of zinc and cobalt was slightly slower than that of copper. It was found that the mass transfer is important in the metal adsorption rate. The surface complex formation model was used successfully to describe the surface change density, as well as the single- and multi-species metal adsorption equilibrium. The copper removal was due to adsorption of Cu2+, CuOH+, and CuCl+, while the zinc and cobalt uptake was due to the formation of surface–metal complexes of SOM2+and SOMOH+(M=Zn and Co). It was found that the diffusion-control model well described the adsorption kinetics with various metal ions and pH values. Finally sensitivity analysis on the kinetic model's parameters was carried out.