CIESC Journal ›› 2018, Vol. 69 ›› Issue (1): 446-454.DOI: 10.11949/j.issn.0438-1157.20170835

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Selective adsorption of Pb2+ by sea urchin magnetic nano-Fe3O4@TiO2

WANG Yaoqiang, ZHAO Yilin, LI Linghui, SU Haijia   

  1. Beijing Key Laboratory of Bioprocess, Beijing University of Chemical Technology, Beijing 100029, China
  • Received:2017-06-29 Revised:2017-10-31 Online:2018-01-05 Published:2018-01-05
  • Contact: 10.11949/j.issn.0438-1157.20170835
  • Supported by:

    supported by the National Natural Science Foundation of China (21525625), the National Basic Research Program of China (2014CB745100) and the National High Technology Research and Development Program of China (2013AA020302).

海胆状Fe3O4@TiO2磁性纳米介质对Pb2+的选择吸附特性

王耀强, 赵怡琳, 李玲慧, 苏海佳   

  1. 北京化工大学, 北京市生物加工过程重点实验室, 北京 100029
  • 通讯作者: 苏海佳
  • 基金资助:

    国家自然科学基金项目(21525625);国家重点基础研究发展计划项目(2014CB745100);国家高技术研究发展计划项目(2013AA020302)。

Abstract:

The sea urchin magnetic nano-Fe3O4@TiO2 particles (SUMNPs) with core-shell structure were prepared by sol-gel technique combined with hydrothermal method. The morphologies and surface areas of SUMNPs were characterized by methods such as TEM and SEM. It was confirmed that the sea-urchin magnetic nanomaterial exhibit Fe3O4 microsphere as core and TiO2 as shell, the diameter of the particles is about 400 nm, the specific surface area is 236.082 m2·g-1, and the surface pore size is about 6.274 nm. The adsorption on heavy metal ions showed that, based on the Pb2+ ion radius is large and the layers of elections is more, in the mixed system of Pb2+, Cd2+, Cu2+, Zn2+ and Ni2+, SUMNPs could adsorb Pb2+ with high capacity and high selectivity, and almost no adsorption of other four heavy metal ions. The single Pb2+ adsorption could be fast equilibrium in 5 min and the equilibrium adsorption capacity was 283 mg·g-1. The adsorption process is in accordance with the Langmuir isothermal adsorption model, and the saturated adsorption capacity is up to 458.72 mg·g-1. After desorbed and regenerated by EDTA disodium and NaOH, SUMNPs can be reused more than 8 times. In summary, SUMNPs have excellent selectivity for Pb2+, and have good application prospect in the treatment of pollution and restoration of water ecological environment.

Key words: hydrothermal synthesis, magnetic nanoparticles, porous media, heavy metal adsorption, thermodynamic properties

摘要:

耦合溶胶-凝胶技术与水热法,制备具有核壳结构的海胆状Fe3O4@TiO2磁性纳米介质(sea urchin magnetic nanoparticles,SUMNPs)。采用TEM、SEM等方法对SUMNPs的形貌等性质进行表征,证实该材料呈现出以Fe3O4为核,以TiO2为壳的海胆状结构,壳层直径约400 nm,比表面积高达236.082 m2·g-1,表面孔径约6.274 nm。SUMNPs对重金属离子选择吸附的结果表明,基于Pb2+离子半径大、电子层数多等物化特点,在Pb2+、Cu2+、Ni2+、Zn2+、Cd2+ 5种金属离子混合体系中,SUMNPs可以高容量、高选择性快速吸附Pb2+,而对其他4种重金属离子几乎无吸附活性。单一Pb2+吸附可在5 min内快速平衡,平衡吸附容量为283 mg·g-1。吸附过程符合Langmuir等温吸附模型,SUMNPs对Pb2+的最大饱和吸附容量为458.72 mg·g-1。经EDTA二钠解吸,NaOH再生后的SUNMPs可以重复使用8次以上。SUMNPs对Pb2+具备优异的选择性吸附性能,在处理水体铅污染、恢复水体生态领域具有良好的应用前景。

关键词: 水热合成, 磁性纳米粒子, 多孔介质, 重金属吸附, 热力学性质

CLC Number: