Treatment of Synthetic Wastewater Containing of Cd(II) Using Novel Magnetic EDTA/Chitosan/TiO2 Nanocomposite

Cadmium, as a heavy metal, has received considerable attention due to its high toxicity, causing excessive damage to health and the biomagnification effects on ecology. In present study, a facile and economic approach has been described for preparing a novel magnetic EDTA/Chitosan/TiO2 (MECT) nanocomposite to remove a wide range of pollutants, especially Cd(ІІ) ions, from aqueous solution.
In this method, not only EDTA has a cheap and environmentally friendly cross-linker function, embeds Fe3O4 nanoparticles in chitosan surface, but also participates in the chelating process of metal ions, caused by functional groups. The morphology, structure, and property of the MECT were characterized by FE-SEM, EDX, and XRD techniques and the effect of different parameters including pH, contact time, and initial cadmium concentration were evaluated.
The results represented that MECT nanoparticles with an average diameter less than 40 nm had the best performance in adsorption of Cd(II) at optimum pH values of 5-6 and contact time of 120 min. Moreover, Langmuir adsorption isotherm is the best fit for the experimental data, in which maximum capacity of Cd(II) adsorption has been achieved 211.416 mg g-1. Finally, reusability of the nanocomposite was measured using Na2EDTA as an elution agent and regeneration efficiency of MECT was observed more than 90% in five successive sorption-desorption cycles.
Thus, magnetic MECT nanocomposite as an environmentally friendly, economical, and recyclable adsorbent has a great potential to develop the industry of water and wastewater treatment.