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论文类型：期刊论文

发表时间：2016-04-01

发表刊物：JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY

收录刊物：SCIE、EI、Scopus

卷号：78

期号：1

页面范围：110-119

ISSN号：0928-0707

关键字：Diatomite; Functionalized mesoporous silica; Adsorption; Cd(II)

摘要：The ordered mesoporous silica functionalized with -NH2 groups was successfully synthesized using diatomite as silica source and used to adsorb Cd(II) ions from aqueous solution. The resultant adsorbent was characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption-desorption measurements, thermogravimetric analysis, the elemental analyzer and transmission electron microscopy. The effects of different concentrations of 3-aminopropyltrimethoxysilane, solution pH, adsorbent dose, contact time were thoroughly investigated. The adsorption kinetic studies were analyzed using pseudo-first-order, pseudo-second-order and intraparticle diffusion models, and the adsorption isotherms were studied by Langmuir and Freundlich isotherm models. The results showed that the adsorption process was successfully fitted with the pseudo-first-order kinetics and Langmuir isotherm models. It was found that the maximum adsorption capacity of adsorbents obtained under optimum synthesis conditions reached 102.9 mg/g at 25 A degrees C, indicating that this new sorbent could have a good potential for the removal of Cd(II) due to its low cost and eco-friendliness.