Adsorption and Selective Separation of Neodymium with Magnetic Alginate Microcapsules Containing the Extractant 2-Ethylhexyl Phosphonic Acid Mono-2-ethylhexyl Ester
Adsorption and Selective Separation of Neodymium with Magnetic Alginate Microcapsules Containing the Extractant 2-Ethylhexyl Phosphonic Acid Mono-2-ethylhexyl Ester
复制标题
萃取剂2-乙基己基膦酸单2-乙基己酯磁性海藻酸微胶囊吸附选择性分离钕
DOI：
10.1021/je101270j
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发表时间：
2011-05-01
期刊：
影响因子：
--
通讯作者：
Wang, Li
中科院分区：
文献类型：
--
作者：
Zhang, Ling;Wu, Dongbei;Wang, Li
以2-乙基己基膦酸单-2-乙基己基酯（P507）为萃取剂，制备了磁性海藻酸微胶囊，采用平衡间歇实验法对钕进行吸附和选择性分离。考察了吸附剂用量、接触时间、温度、pH值、金属离子浓度等因素对吸附效果的影响。结果表明，吸附数据符合准二级动力学模型，Langmuir吸附等温线适合描述吸附过程。单组分和多组分体系的吸附容量顺序为Pb ~（2+）> Nd ~（3+）> Cu ~（2+）> Zn ~（2+）> Co ~（2+）> Ni ~（2+），在整个浓度范围内，Nd ~（3+）均能从Nd ~（3+）/Co ~（2+）和Nd ~（3+）/Zn ~（2+）混合溶液中选择性分离。此外，溶剂萃取和离子交换机制被证实有助于通过FTIR光谱研究，pH值分析，吸附等温线与可能的结构提出的复杂的吸附过程。热重分析、脱附和再生实验表明，磁性海藻酸盐P507微胶囊具有良好的工业应用前景。
Magnetic alginate microcapsules containing the extractant 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (P507) were prepared for adsorption and selective separation of neodymium using equilibrium batch experiments. The effect of various parameters such as adsorbent dose, contact time, temperature, pH, and metal ion concentration on adsorption was investigated. The results demonstrated that the adsorption data fit well the pseudosecond order kinetic model, and the Langmuir adsorption isotherm was suitable for the description of adsorption process. The adsorption capacity had the order Pb2+ > Nd3+ > Cu2+ > Zn2+ > Co2+ > Ni2+ for mono- and multicomponent systems, and Nd3+ could be selectively separated from the mixed Nd3+/Co2+ and Nd3+/Zn2+ solutions over the whole concentration range. Furthermore, solvent extraction and ion exchange mechanisms were confirmed to contribute to the adsorption process by FTIR spectra studies, pH analyses, and adsorption isotherms with possible structures of the complex proposed. Thermogravimetric analysis, desorption, and regeneration tests forecasted that the magnetic alginate P507 microcapsules would be an excellent candidate for their potential industrial application.