Box Behenken design optimization for heavy metal sorption on novel magnetic amino/thiol functionalized nanoparticles

In this study, a novel amino/thiol functionalized superparamagnetic nanoparticle was synthesized and applied as an effectual nanosorbent to uptake Pb2+ and Cd2+. To synthesize the amino/thiol magnetic nanoparticles (Fe3O4@SiO2-N2S), Fe3O4@SiO2 was functionalized by thio-(3-Glycidyloxopropyl)trimethoxysilan (GLYMO-S) and modified by ring-opening reaction between GLYMO-S and ethylenediamine. The magnetic nanoparticles (MNPs) were characterized by transmission electron microscopy (TEM), Field emission scanning electron microscopy (FE-SEM), X-ray powder diffraction (XRD), thermo gravimetric analysis (TGA), vibrating sample magnetometer (VSM) and Fourier transform infrared spectroscopy (FT-IR) and confirmed the presence of nitrogen and sulfur containing functional groups on Fe3O4@SiO2 MNPs. To investigate the effective parameters and optimize the removal conditions, the Box Behnken Design (BBD) based on response surface methodology (RSM) was applied. In optimum conditions Fe3O4@SiO2-N2S adsorbed Pb2+ (93.5 mg g-1) and Cd2+ (80.64 mg g-1) at pH 7, adsorbent dosage 16 mg and contact time 55 min. The data revealed the heavy metal ions removal followed the Pseudo-second-order kinetic model (R2 = 0.98) and Langmuir isotherm (R2 = 0.99). The Fe3O4@SiO2-N2S MNPs can simultaneously adsorb Pb2+, Cd2+ and Cu2+. The reusability of Fe3O4@SiO2-N2S was utilized at five cycles and removal of Pb2+ and Cd2+ conserved above 90%. The results show that the novel amino/thiol functionalized MNPs can successfully apply as an efficient and reusable nanosorbent with a high adsorption rate in removing heavy metal ions from wastewater

کلیدواژه ها:

amino/thiol functionalized nanoparticle ، box behnken design ، magnetic nanosorbent ، heavy metal uptake ، reuse and regeneration