Fabrication of core-shell structured Fe3O4@amide humic acid magnetic nanoparticles and their highly efficient adsorption for La (III)

The enhancement and removal of rare earth ions from wastewater resources have emerged as a crucial study to ensure the superior quality of rare earth resources application. In this work, amide humic acid-coated Fe3O4 magnetic nanoparticles (Fe3O4@AHA MNPs) were fabricated by chemical coprecipitation hydrothermal technique. The fabricated nanoparticles showed excellent stability in aqueous solutions. They could be easily collected from solutions using a magnetic separation strategy. Adsorption studies were used to investigate the adsorption performance of Fe3O4@AHA MNPs for La (III) under a variety of circumstances. Furthermore, isothermal adsorption lines and kinetic and thermodynamic modeling were used to examine the adsorption mechanism of La (III). Results revealed that Fe3O4@AHA MNPs had a high adsorption capacity of 148.83 mg g−1 and adsorption equilibrium was attained after 45 min when the adsorbent dose was 20 mg at pH 6. Fe3O4@AHA MNPs demonstrated high reusability for La (III), retaining 78.5% of initial adsorption capability after five cycles. Finally, the fabricated Fe3O4@AHA MNPs was successfully employed and applied to remove La (III) from industrial wastewater samples. According to these results, the Fe3O4@AHA MNPs have potential to be a useful material for enrichment and preconcentration of La (III) or other trivalent lanthanides from wastewater.