Synthesis and characterization of Fe3O4@SiO2 nanoparticles functionalized with glucosamine as an effective and magnetic adsorbent with recycling capability in removing Ni2+ ions from aqueous solutions

In the present study, magnetite nanoparticles were synthesized by co-precipitation method with surface coating by silica nanoparticles. Afterwards, these nanoparticles were functionalized with glucosamine molecules. In the next step, these functionalized core-shell nanoparticles were used as a suitable adsorbent to remove nickel ions from aqueous solutions.

The synthetic adsorbent was investigated using techniques such as X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), particle size distribution (DLS), vibrating sample magnetometer (VSM), X-ray energy diffraction (EDX) and thermogravimetric analysis (TGA) to evaluate the structure, morphology and size of the particles. Moreover, the absorption performance of the synthetic adsorbent was investigated by optimizing the amount of adsorbent, pH of the solution and contact time.

The results indicate that the maximum absorption capacity occurs when 24 mg of the adsorbent is added to 75 mL of the solution with an initial concentration of 0.65 mmol/L at pH=7 with contact time of 18 min. Additionally, the synthetic adsorbent possess the ability to be recovered and used repeatedly in successive absorption processes up to 7 times without a serious decrease in activity.