Kinetics and equilibrium studies from the methylene blue adsorption on diatomite treated with sodium hydroxide
Kinetics and equilibrium studies from the methylene blue adsorption on diatomite treated with sodium hydroxide
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氢氧化钠处理的硅藻土吸附亚甲基蓝的动力学和平衡研究
DOI：
10.1016/j.clay.2013.08.008
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发表时间：
2013-10
影响因子：
5.6
通讯作者：
张健
中科院分区：
文献类型：
--
作者：
张健
为了提高硅藻土的吸附性能，采用氢氧化钠对硅藻土进行了除杂处理。采用扫描电镜、X射线能谱分析和Brunauer-Emmett-Teller吸附等方法对粗品和纯品进行了表征。结果发现，未加工的氧化铝的表面积约为15.87 m2 g − 1，纯化的氧化铝的表面积约为31.35 m2 g − 1。扫描电子显微镜图像显示了纯化的纳米纤维的发达的多孔结构。对亚甲基蓝初始浓度为100 ppm时，纯化后的硅藻土吸附量从1.72 mg g-1提高到18.15 mg g-1，去除率从8.60%提高到90.75%。动力学研究表明，实验数据较好地符合准二级动力学模型。将平衡数据拟合为Langmuir和Freundlich吸附等温线，发现Langmuir模型表现出最佳拟合，显示最大单层吸附容量为27.86 mg g− 1。计算了标准焓、标准熵和标准自由能等热力学参数。实验结果表明，经氢氧化钠处理的硅藻土对亚甲基蓝的吸附是吸热的自发过程，证实了这种无机材料作为碱性染料的有效吸附剂的适用性。
Diatomite was treated with sodium hydroxide to remove impurity in order to improve its performance as an adsorbent. The raw diatomite and purified diatomite were characterized by scanning electron microscopy, energy dispersive X-ray analysis and Brunauer–Emmett–Teller adsorption. It was found that the surface area was in order of 15.87 m2g− 1for raw diatomite and 31.35 m2g− 1for purified diatomite. Scanning electron microscopy images showed the well-developed porous structure of purified diatomite. Purified diatomite improved a more than tenfold increase in adsorption amount from 1.72 mg g− 1to 18.15 mg g− 1and removal efficiency from 8.60% to 90.75% for methyelen blue initial concentration 100 ppm respectively. The kinetics studies showed that experiment data followed pseudo-second-order model better. The equilibrium data was fitted to Langmuir and Freundlich adsorption isotherms and was found that Langmuir model presented the best fit, showing maximum monolayer adsorption capacity of 27.86 mg g− 1. The thermodynamic parameters such as the standard enthalpy, standard entropy and standard free energy were evaluated. The obtained results indicated the adsorption of methylene blue onto diatomite treated with sodium hydroxide is endothermic and spontaneous process and confirmed the applicability of this purified inorganic material as an efficient adsorbent for basic dyes.
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影响因子：
15.1
作者：
Al-Ghouti, MA;Khraisheh, MAM;Tutuji, M
通讯作者：
Tutuji, M
影响因子：
--
作者：
Freundlich, H
通讯作者：
Freundlich, H
影响因子：
5.6
作者：
Kiani, Gholamreza;Dostali, Mohammad;Khataee, Ali R.
通讯作者：
Khataee, Ali R.
影响因子：
5.6
作者：
M. Šljivić;I. Smičiklas;S. Pejanović;I. Plećaš
通讯作者：
M. Šljivić;I. Smičiklas;S. Pejanović;I. Plećaš
DOI：
10.1002/jctb.5040350106
发表时间：
2007-05
期刊：
Journal of Chemical Technology and Biotechnology. Chemical Technology
影响因子：
--
作者：
H. Asfour;M. Nassar;O. Fadali;M. S. El-Geundi
通讯作者：
H. Asfour;M. Nassar;O. Fadali;M. S. El-Geundi