Fabrication and Characterization of Zinc Oxide Nanoparticles for the Preconcentration of Lead(II) in Milk and Water with Detection by Flame Atomic Absorption Spectrometry

A method is reported for the immobilization of iminodiacetic acid on zinc oxide nanoparticles modified by N-[2-aminoethyl]-3aminopropyltrimethoxysilane. The nanosorbent was characterized by infrared spectroscopy, elemental analysis, thermogravimetric analysis, and scanning electron microscopy. The preconcentration and determination of trace Pb(II) were characterized in environmental water and milk. The optimum pH for sorption of the metal was 7. The sorption capacity of sorbent was 51mg g(-1). A high recovery of Pb(II) ions was obtained from 81 to 100% with 0.5M nitric acid as the elution solvent. The reported nanosorbent provided high accessibility of active chelating sites in the modified zinc oxide nanoparticles. The equilibrium adsorption of Pb(II) by this sorbent were characterized by Langmuir, Freundlich, Temkin, and Redlich-Peterson models.