Removal of Pb (II) from aqueous solution by gel combustion of a new nano sized Co3O4-ZnO composite

Nano Co3O4/ZnO have been successfully synthesized by a simple and green gel combustion method followed by calcination at 600 o C. Sugar was used as fuel for combustion in this work. The nano Co3O4–ZnO were characterized by X-ray diffraction (XRD), Energy Dispersive XRay analysis (EDAX) and Scanning electron microscopy (SEM). Co3O4–ZnO was applied as an adsorbent to remove lead from aqueous solution. EDAX strongly proved the adsorption of lead on the surface of Co3O4-ZnO adsorbent. By increasing the amount of ZnO on the structure of the Co3O4-ZnO samples, the adsorption of Pb2+ on the surface increased too. The SEM images also help the confirmation of lead adsorption on the surface of as synthesized samples. The concentrations of remained Pb2+ ions were also measured by atomic absorption spectroscopy (AAS) and reported in the terms of removal efficiency.