Removal of metal ions using a new magnetic chitosan nano-bio-adsorbent; A powerful approach in water treatment

In this study, a magnetic chitosan/Al2O3/Fe3O4 (M-Cs) nanocomposite was developed by ethylenediaminetetraacetic acid (EDTA) functionalization to enhance its adsorption behavior for the removal of Cd (II), Cu(II) and Zn(II) metal ions from aqueous solution. The results revealed that the EDTA functionalization of M-Cs increased its adsorption capacity -9.1, -5.6 and -14.3 times toward Cu, Cd and Zn ions. The maximum adsorption capacity followed the order of Cd(II) > Cu(II) > Zn(II) and the maximum adsorption efficiency was achieved at pH of 5.3 with the removal percentage of 99.98, 93.69 and 83.81 %, respectively, for the removal of Cu, Cd and Zn ions. The metal ions adsorption kinetic obeyed pseudo-second-order equation and the Langmuir isothermal was found the most fitted model for their adsorption isothermal experimental data. In addition, the thermodynamic study illustrated that the adsorption process was exothermic and spontaneous in nature.

Automated summary

The study demonstrated that the EDTA functionalization of M-Cs nanocomposite significantly enhanced its adsorption capacity for Cu, Cd, and Zn ions. The maximum adsorption capacity followed the order of Cd(II) > Cu(II) > Zn(II) with the highest efficiency achieved at pH 5.3. The adsorption process was found to be exothermic and spontaneous in nature.