Synthesis of ZnO nanoparticles and its application in adsorption

In the present study nanoparticles of zinc oxide (ZnO) were synthesized by simple solution based approach and used as an adsorbent for the removal of Cu(II) ions from aqueous solution. ZnO nanoparticles were characterized by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS). TEM confirmed the formation of zinc oxide nanoparticles in the size range of 10-11 nm. Adsorption capacity of ZnO for removing Cu(II) ions from aqueous solutions was investigated at different pH, as a function of contact time, metal ion concentration and the amount of adsorbent. Moreover, adsorption isotherms and kinetics was studied to understand the nature and mechanism of adsorption. A high percentage removal  (98.71%) of Cu(II) from its aqueous solutions at pH 5 and  at initial heavy metal ion concentration of 300 mg/l by ZnO particles was achieved. The adsorption isotherm was well described by Freundlich isotherm model(R2= 0.999). The adsorption kinetics data was well fitted by the pseudo-second-order rate model with a high regression coefficient. The  above results suggest that ZnO nanoparticles can be used as  potential adsorbent for the efficient removal of heavy metals from aqueous solutions. Copyright © 2017 VBRI Press