Removal of Cu(II) from aqueous solution by adsorption onto functionalized SBA-16 mesoporous silica
Removal of Cu(II) from aqueous solution by adsorption onto functionalized SBA-16 mesoporous silica
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DOI：
10.1016/j.micromeso.2008.03.023
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发表时间：
2008-12
影响因子：
5.2
通讯作者：
Xiaoming Xue;Fengting Li
中科院分区：
文献类型：
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作者：
Xiaoming Xue;Fengting Li
采用一锅法合成了含-SH基团的功能化SBA-16介孔二氧化硅。用粉末X-射线衍射仪、氮气吸附、FT-拉曼光谱对所得材料进行了表征。在室温下，该固体被用作水溶液中的铜(II)吸附剂。用间歇法研究了几个变量(搅拌时间、pH值、金属浓度和介质中其他离子的存在)对测定结果的影响。结果表明，通过控制正硅酸乙酯(TEOS)和3-巯丙基三乙氧基硅烷(TMMPS)的最佳摩尔比为3：4，合成的材料对铜离子具有较高的有序性和吸附容量，但由于有机官能团在介孔孔道上的吸附，材料的孔径有所减小。在pH为5~6的范围内，该吸附剂对Cu2+的最大吸附量为36.38 mg/g，吸附符合Redlich-Peterson等温式(R2=0.9999)和朗缪尔方程(R2=0.9847)。其机理可能是通过与-SH基团的配基交换进行吸附。水溶液中的吸附竞争阳离子对铜离子在该吸附剂上的吸附影响不大。不同阴离子(Cl-−、NO_3~-、SO_4~(2-)、OAc~(−)和Cit_−)对Cu2+吸附的影响顺序为：NO_3~-<；OAc-<；SO_4~-<；Cit-<；即使经过7次再生，功能化的SBA-16介孔分子筛对铜(II)的吸附量也在23 mg/g以上，而且可以很容易地通过酸洗进行再生，在处理含铜(II)废水方面具有良好的应用前景。
Functionalized SBA-16 mesoporous silica with –SH groups was synthesized using one-pot method. The resulting material was characterized by powder X-ray diffraction, nitrogen gas sorption, FT-Raman spectroscopy. The solid was employed as a Cu(II) adsorbent from aqueous solutions at room temperature. The effects of several variables (stirring time, pH, metal concentration and presence of other ions in the medium) were studied using the batch technique. The results showed that by controlling an optimum molar ratio of 3–4 between tetraethyl orthosilicate (TEOS) and 3-mercaptopropyltriethoxysilane (TMMPS), the synthesized material possessed high order and adsorption capacity for Cu(II) ions though the pore size decreased probably due to the attachment of the organic functional groups in the mesopore channels. The maximum Cu(II) adsorption on this adsorbent occurred in the range of pH 5–6 with an adsorption maximum of 36.38mg/g. The adsorption of Cu(II) on functionalized SBA-16 mesoporous fitted well to the Redlich–Peterson isotherm equation (r2=0.9999) followed by the Langmuir equation (r2=0.9847). The involved mechanism might be the adsorption through ligand exchange with the –SH group. The adsorptive competing cations in the aqueous solution had a little effect on the adsorption of Cu(II) on this adsorbent. The presence of different anions (Cl−, NO3-, SO42-, OAc−and Cit−) influenced the Cu(II) adsorption in the order of NO3-<OAc-<SO42-<Cit-<Cl-. Even after seven regeneration cycles, functionalized SBA-16 mesoporous had a Cu(II) adsorption amount of over 23mg/g and could be easily regenerated through acid washing, showing a promising application for the treatment of wastewater containing Cu(II) ions.