Synthesis of Nanocomposite ZnO and MnO2 Nanoparticles and Its Applications for Determination of Heavy Metals in Water

Environmental pollution is the result of the rapid development of industry, which is a serious problem. In this research, first ZnO nanoparticles were synthesized by hydrothermal method and then added to the preparation solution of MnO2 nanoparticles by precipitation during reduction reaction. The particle size was studied by Scanning electron microscopy (SEM). The prepared ZnO/MnO2 nanocomposite was used as a solid phase adsorbent to separate and determine the heavy metal ions of lead and cadmium in water samples. The removal efficiency of heavy metal ions and desorption conditions were determined by atomic absorption spectrometry. The effect of various parameters such as pH, amount of adsorbent, initial concentration of ions, shaking time, sample volume, and eluent type and concentration for elution of the retained heavy metal ions were evaluated and the optimum conditions were determined. The relative standard deviations for the determination of lead and cadmium ions were 4.6 -5.2% and 1.7-3.4%, respectively.