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

Abstract

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 2 h. 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.

Keywords:

• Fulvic acid
• Magnetite
• Coated
• Attenuation
• Geochemical parameters

Acknowledgments

Financial supports from department of Science and Technology, Zhejiang province (2010C33101), financial supports from the National Natural Science Foundation of China (90610030) are acknowledged.