An efficient removal of lead from aqueous solutions using FeNi3@SiO2 magnetic nanocomposite

The aim of the present study was the synthesis of nickel ferrite magnetic nanoparticles functionalized with SiO2 using Stöber method for its application to remove lead from the water. To determine the characteristics of the synthesized magnetic nano-composite, different analysis tools were used including, Fourier transforms infrared spectrometer, X-ray diffraction analysis, Vibrating sample magnetometer and Transmission electron microscopy. Results of Vibrating sample magnetometer analysis showed that FeNi3@SiO2 have typical soft magnetic traits and extraordinary para-magnetism at room temperature. The successful conjugation of SiO2 onto the surface of FeNi3 nanoparticles was confirmed by Fourier transform infrared spectroscopy. Transmission electron microscopy images of FeNi3@SiO2 magnetic nano-composite showed particle size of around 30 nm. The optimum conditions for lead removal from the water were obtained at pH 6, 300 mg/L adsorbent dose and 20 min contact time, wherein in these circumstances the removal of lead was 87.31%. The adsorption isotherms primacy was as follows, Freundlich R2 = 0.9889 > Langmuir R2 = 0.9539 > Temkin R2 = 0.9268. Also, investigation of adsorption kinetics of pseudo-first and second orders indicated that lead adsorption by FeNi3@SiO2 followed the pseudo-second-order with the higher correlation coefficient of R2 = 0.9994.