Impact of key geochemical parameters on the attenuation of Pb(II) from water using a novel magnetic nanocomposite: fulvic acid-coated magnetite nanoparticles

In recent years, magnetic nanoparticles have been widely utilized as promising adsorbents for fast and effective attenuation of metal ions in water in environmental pollution control. Herein, a novel magnetic nanocomposite, namely fulvic acid (FA)-coated Fe3O4 nanoparticles (Fe3O4/FA), was utilized for the attenuation of Pb(II) in water by an adsorption process. The results indicated that the coated FA reduced the surface oxidation and agglomeration of Fe3O4 particles and thus promoted the performance of Fe3O4/FA towards Pb(II) removal. The results indicate that Pb(II) adsorption on Fe3O4/FA obtained equilibrium in less than 2h. Besides, the adsorption of Pb(II) on Fe3O4/FA is strongly dependent on medium pH, and independent of ionic strength and the type of coexisted ions. So, inner-sphere surface complexation mainly controls Pb(II) uptake on Fe3O4/FA. The Fe3O4/FA also showed good regeneration property and separation convenience for the treatment of Pb(II). Besides, XPS is used to study the mechanism at a molecular level and to identify the species of Pb(II) on Fe3O4/FA. Results of this study showed that the magnetic Fe3O4/FA is a promising sequestrator for the attenuation and separation of heavy metal ions in water in environmental pollution cleanup.