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采用化学共沉淀法原位制备了一种可便于磁性回收并吸附水中重金属离子(如Pb~(2+))的磁性纳米伊/蒙黏土。通过X射线衍射、Fourier变换红外光谱、场发射扫描电子显微镜、振动样品磁强计对样品进行了表征。结果表明:合成的Fe_3O_4纳米颗粒可原位复合附着于纳米伊/蒙黏土颗粒表面,使磁性纳米伊/蒙黏土的饱和磁化强度达到26.77 A·m~2/kg,并可有效地从浆体中磁分离出来。另外,水中Pb~(2+)的吸附研究表明,磁性纳米伊/蒙黏土吸附Pb~(2+)的动力学过程符合准二级动力学模型,且pH值和磁性纳米伊/蒙黏土加入量对在浆料中吸附Pb~(2+)的效果有着显著的影响。其等温吸附过程符合Langmuir模型,其最大单层饱和吸附量为22.5 mg/g。当pH=6时,Pb~(2+)的去除率达97.79%;当磁性纳米伊/蒙黏土加入量为1 g/L时,平衡吸附量为38.7 mg/g。
In situ preparation by chemical coprecipitation, a magnetic nano-imide / montmorillonite that can be used for magnetic recovery and adsorption of heavy metal ions (such as Pb 2+) in water can be prepared. The samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, vibrating sample magnetometer. The results show that the synthesized Fe_3O_4 nanoparticles can be attached to the surface of the nano-Ii / Montmorillonite particles in situ and the saturation magnetization of the magnetic nano-Ii / Montmorillonite reaches 26.77 A · m ~ 2 / kg, Magnetic separation. In addition, the adsorption of Pb 2+ in water shows that the kinetics of adsorption of Pb 2+ by the magnetic nano-Ii / Montmorillonite accords with quasi-second-order kinetic model, and the addition of pH and magnetic nano-I / The amount of Pb ~ (2+) in the slurry has a significant effect on the effect. The isothermal adsorption process conforms to the Langmuir model, and the maximum monolayer adsorption capacity is 22.5 mg / g. When pH = 6, the removal rate of Pb 2+ reached 97.79%. When the amount of magnetic nani / clay was 1 g / L, the equilibrium adsorption capacity was 38.7 mg / g.