Simultaneous adsorption of Cd2+ and BPA on amphoteric surfactant activated montmorillonite
Simultaneous adsorption of Cd2+ and BPA on amphoteric surfactant activated montmorillonite
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两性表面活性剂活化蒙脱土同时吸附Cd2和BPA
DOI：
10.1016/j.chemosphere.2015.09.063
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发表时间：
2016-02-01
期刊：
影响因子：
8.8
通讯作者：
Tran, Lytuong
中科院分区：
文献类型：
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作者：
Liu, Chongmin;Wu, Pingxiao;Tran, Lytuong
研究了十八烷-甜菜碱改性蒙脱土（BS-Mt）对水溶液中双酚A（BPA）和Cd 2+的同时吸附。通过X射线衍射（XRD）、傅里叶变换红外（FOR）、比表面积（BET）和扫描电子显微镜/能谱（SEM/EDS）对所得材料进行了表征，证实BS-18成功地引入到Mt.初始溶液pH、Cd 2 +/BPA初始浓度、接触时间和吸附剂用量对吸附过程的影响较大，而对BPA吸附的影响较小。结果表明，吸附动力学符合准二级动力学模型，吸附平衡时间为24 h。Cd ~（2+）和BPA的吸附等温线分别符合Freundlich模型和Langmuir模型。动力学模型表明，改性后BS-Mt对Cd 2+的最大吸附量略有提高，说明BS-Mt对Cd 2+的吸附主要是通过直接静电吸引和螯合反应实现的，而对BPA的最大吸附量的大幅提高则是由于疏水作用。(C)2015爱思唯尔有限公司版权所有。
The study mainly investigated the simultaneous adsorption of bisphenol A (BPA) and Cd2+ from aqueous solution on octadecane-betaine modified montmorillonite (BS-Mt). The characteristics of the obtained materials were analyzed by X-ray diffraction (XRD), Fourier-transform infrared (FOR), Specific surface area (BET) and Scanning electron microscopy/Energy disperse spectroscopy (SEM/EDS), confirming that BS-18 was successfully introduced into Mt. Also, factors including initial solution pH, initial Cd2+/BPA concentration, contact time and adsorbent dosage on the adsorption processes were shown to be crucial for Cd2+ adsorption, whereas had negligible effects on BPA adsorption. In this study, we found that pseudo-second-order model fitted well with the adsorption kinetic studies for both Cd2+ and BPA with an equilibrium time of 24 h. The Cd2+ and BPA adsorption isotherm could be well described by Freundlich model and Langmuir model, respectively. On the basis of kinetic models, the maximum adsorption capacity of Cd2+ in aqueous solution was slightly enhanced after modification, indicating that Cd2+ adsorption on BS-Mt was mainly attributed to direct electrostatic attraction and the chelate reaction, while the dramatic enhancement of maximum adsorption capacity for BPA was due to the hydrophobic interaction. (C) 2015 Elsevier Ltd. All rights reserved.