Preparation, characterization and application of CS@PDA@Fe3O4 nanocomposite as a new magnetic nano-adsorber for the removal of metals and dyes in wastewater

Abstract

This study aimed to develop a novel magnetic chitosan/dopamine/Fe₃O₄ nano-adsorber (CS@PDA@Fe₃O₄) for the removal of heavy metal ions and organic dye molecules from aqueous solution. CS@PDA@Fe₃O₄ was prepared by surface modification of PDA/Fe₃O₄ nanoparticles with chitosan using IPTES as the cross-linker. The surface structure, composition, and properties of the CS@PDA@Fe₃O₄ nano-adsorber were characterized by elemental (EDS), spectroscopic (XRD, XPS, and FT-IR), magnetic intensity (VSM), surface and morphological (TEM and SEM) analyses. In order to study its adsorption behavior, equilibrium and kinetics studies were carried out through batch experiments. Additionally, the influences of the pH value, initial concentration, adsorbent dose, and contact time were also evaluated. The CS@PDA@Fe₃O₄ nano-adsorber exhibited high adsorption capacity especially for Cu(II), with a maximum adsorption capacity of 419.6 mg g⁻¹. The experimental data were well described by the Langmuir isotherm kinetic models.