Disulfide Cross-Linked Poly(Methacrylic Acid) Iron Oxide Nanoparticles for Efficiently Selective Adsorption of Pb(II) from Aqueous Solutions.

ABSTRACT: The efficient selectivity of heavy metal ions from wastewater is still challenging but gains great public attention in water treatment on a world scale. In this study, the novel disulfide cross-linked poly(methacrylic acid) iron oxide (Fe₃O₄@S-S/PMAA) nanoparticles with selective adsorption, improved adsorption capability, and economic reusability were designed and prepared for selective adsorption of Pb(II) ions in aqueous solution. In this study, nuclear magnetic resonance, dynamic light scattering, scanning electron microscopy, X-ray diffraction, vibrating sample magnetometry, and thermogravimetric analysis were utilized to study the chemophysical properties of Fe₃O₄@S-S/PMAA. The effect of different factors on adsorption properties of the Fe₃O₄@S-S/PMAA nanoparticles for Co(II) and Pb(II) ions in aqueous solution was explored by batch adsorption experiments. For adsorption mechanism investigation, the adsorption of Fe₃O₄@S-S/PMAA for Co(II) and Pb(II) ions can be better fitted by a pseudo-second-order model, and the adsorption process of Fe₃O₄@S-S/PMAA for Co(II) and Pb(II) matches well with the Freundlich isotherm equation. Notably, in the adsorption experiments, the Fe₃O₄@S-S/PMAA nanoparticles were demonstrated to have a maximum adsorption capacity of 48.7 mg·g^-1 on Pb(II) ions with a selective adsorption order of Pb²⁺ > Co²⁺ > Cd²⁺ > Ni²⁺ > Cu²⁺ > Zn²⁺ > K⁺ > Na⁺ > Mg²⁺ > Ca²⁺ in the selective experiments. In the regeneration experiments, the Fe₃O₄@S-S/PMAA nanoparticles could be easily recovered by desorbing heavy metal ions from the adsorbents with eluents and showed good adsorption capacity for Co(II) and Pb(II) after eight recycles. In brief, compared to other traditional nanoadsorbents, the as-prepared Fe₃O₄@S-S/PMAA with improved adsorption capability and high regeneration efficiency demonstrated remarkable affinity for adsorption of Pb(II) ions, which will provide a novel technical platform for selective removal of heavy metal ions from actual polluted water.

SUBMITTER: Wang R 

PROVIDER: S-EPMC7808134 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature