磁性Fe3O4@SiO2@ZrO2对水中磷酸盐的吸附研究  

Phosphate Adsorption on Magnetic Fe_3O_4@SiO_2@ZrO_2

作　　者：王文娟[1] 张海鹏[1] 韩玉香[1] 郑寿荣[1] 许昭怡[1] 

机构地区：[1]污染控制与资源化研究国家重点实验室、南京大学环境学院,南京210023

出　　处：《无机化学学报》2014年第12期2726-2732,共7页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金(No.21077050,21277069);国家“863”计划(No.2012AA062607)资助项目

摘　　要：合成了以Fe3O4为核,以SiO2为壳的磁性纳米微粒(Fe3O4@Si O2),并采用沉淀沉积法将ZrO2包覆到材料表面。通过XRD、TEM、VSM、ζ电位、XPS和N2吸附/脱附等手段对材料进行表征,结果表明材料Fe3O4@SiO2@ZrO2上沉积了氧化锆纳米颗粒,具有超顺磁性,可在外加磁场作用下实现从水中快速分离。同时系统研究了材料对水中磷酸盐的吸附行为,结果表明沉积Zr O2使得材料对磷酸盐表现出良好的吸附性能,并且随着沉积量的增大吸附量增加。吸附等温线符合Freundlich方程。吸附动力学可用拟二级动力学模型描述,吸附速率随磷酸盐初始浓度增加而减小。磷酸盐吸附量随溶液p H值的增大而减小,但几乎不受离子强度影响。We prepared silica-coated core-shell magnetite nanoparticles （Fe3O4@SiO2） which was subsequently coated by ZrO2 via the deposition precipitation method. The adsorbents were characterized by X-ray diffraction, transition electron microscopy, vibration sample magnetometer, N2 adsorption/desorption, zeta-potential measurement, and X-ray photoelectron spectroscopy. The results demonstrated the adsorbents could be readily separated and recovered under external magnetic field. Additionally, the adsorption capacity for phosphate increased with the amount of ZrO2 loading, indicating that ZrOz is effective adsorption sites for phosphate. The adsorption was fitted well with Freundlich adsorption isotherm and the kinetics was well described by the pseudo- second-order model. Phosphate adsorption on Fe3O4@SiO2@ZrO2 increased with the decrease in pH value. Negligible influence of the ion strength on phosphate adsorption was observed.

关 键 词：磁性氧化锆 磷酸盐 吸附 水污染控制 

分 类 号：O614.412[理学—无机化学] O614.811[理学—化学]