Fabrication of amino-functionalized CoFe2O4-SiO2 magnetic composites and their adsorption performance for removal of heavy metal ions from water

Abstract:

The cobalt-ferrite nanoparticles (CoFe₂O₄ NPs) were prepared using the modified co-precipitation method and the CoFe₂O₄-SiO₂ magnetic composites were synthesized via st?ber step. The CoFe₂O₄-SiO₂ was also amino-functionalized to adsorb heavy metal ions. The crystalline phase, morphologies, particle size, chemical compositions and chemical structure of the absorbent have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The composites exhibited excellent magnetic properties with high saturated magnetization and can be separated by a magnet within 30 seconds, and the saturation magnetization (Ms) of CoFe₂O₄ NPs can be adjusted by sintering temperature,increased with increasing the temperature. The effect of pH and reaction time on the adsorption of CoFe₂O₄-SiO₂-NH₂ for Cu (II) was examined. And the amino-functionalized CoFe₂O₄-SiO₂ (CoFe₂O₄-SiO₂-NH₂) showed high adsorption capacity and the removal efficiency for Cu (II), Cd (II), Zn (II) and Mn (II), which makes great potential application on the heavy metal wastewater treatment.

Key words:cobalt-ferrite; SiO₂; magnetism; adsorption; heavy metal