【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。更多还原

【Abstract】 We prepared silica-coated core-shell magnetite nanoparticles(Fe3O4@Si O2) which was subsequently coated by Zr O2 via the deposition precipitation method. The adsorbents were characterized by X-ray diffraction,transition electron microscopy, vibration sample magnetometer, N2adsorption/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 Zr O2 loading, indicating that Zr O2 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@Si O2@Zr O2 increased with the decrease in p H value.Negligible influence of the ion strength on phosphate adsorption was observed.更多还原