Sorption of Ni2+ on Na-rectorite studied by batch and spectroscopy methods
Sorption of Ni2+ on Na-rectorite studied by batch and spectroscopy methods
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间歇法和光谱法研究钠累托石对 Ni2 的吸附
DOI：
10.1016/j.apgeochem.2008.07.008
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发表时间：
2008-09-01
影响因子：
3.4
通讯作者：
Wang, Xiangke
中科院分区：
文献类型：
--
作者：
Tan, Xiaoli;Chen, Changlun;Wang, Xiangke
研究了在常温下，Ni ~（2+）在钠基累托石上的吸附行为与时间、温度、pH值和富里酸（FA）/胡敏酸（HA）的关系。采用准二级速率方程模拟吸附动力学过程。Ni 2+的去除率随着pH值的增加而增加。FA/HA的存在增强了Ni 2+在低pH值下的吸附，而FA/HA对累托石对Ni 2+的吸收没有显著影响。扩散层模型（DLM）拟合Ni 2+吸附在FA/HA的存在和不存在下的实验数据非常好的帮助下FlTEQL 3.2。采用Langmuir、Freundlich和Dubininin-Radushkevich（D-R）模型对不同温度下的吸附等温线进行了模拟。由吸附等温线计算得到的热力学数据（AW，阿索，AGO）表明累托石对Ni 2+的吸附是自发的吸热过程。采用XPS研究了累托石对Ni ~（2+）的吸附行为，并对Ni ~（2+）在累托石上的形态进行了表征。光谱分析表明，Na-累托石的结构没有发生剧烈的变化，Ni 2+的吸附主要发生在Na-累托石的表面和边缘位置。(c)2008爱思唯尔有限公司保留所有权利。
Sorption of Ni2+ on Na-rectorite as a function of contact time, temperature, pH and fulvic acid (FA)/humic acid (HA) was studied under ambient conditions. A pseudo-second-order rate equation was used to simulate the kinetic sorption. The removal of Ni2+ increased with increasing pH. The presence of FA/HA enhanced the sorption of Ni2+ at low pH values, whereas no drastic effect of FA/HA on Ni2+ uptake to rectorite was found at high pH values. The diffuse layer model (DLM) fitted the experimental data of Ni2+ sorption in the absence and presence of FA/HA very well with the aid of FlTEQL 3.2. The Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models were used to simulate the sorption isotherms of Ni2+ at different temperatures. The thermodynamic data (AW, ASO, AGO) were calculated from the temperature dependent sorption isotherms and the results suggested that the sorption process of Ni2+ on rectorite was spontaneous and endothermic. The sorption and species of Ni2+ on rectorite in the presence and absence of FA/HA was also investigated and characterized by XPS. The spectroscopic analysis indicated no drastic structural changes of Na-rectorite and the sorption of Ni2+ mainly occurred on the surface and at the edge position of Na-rectorite. (c) 2008 Elsevier Ltd. All rights reserved.