Baobab Leaves and its Potential in the Synthesis of Zinc Oxide Nanoparticles for the Removal of Lead and Copper from Aqueous Solution

Abstract

Nanoparticles are materials with a size less than ∼100 nm in diameter and they exhibit unique properties due to their nanoscale dimensions. This work aimed at determining the potentials of baobab leaves in the synthesis of ZnO nanoparticles for heavy metal removal in waste water. Phytochemicals were determined using standard laboratory methods. The green synthesis method was used to synthesise the ZnO nanoparticle. It was characterised using X-ray diffraction, Fourier transformed infrared spectroscopy, UV-visible spectroscopy, scanning electron microscopy and atomic adsorption spectroscopy. Taguchi method with L16 orthogonal array robust design was implemented to optimize experimental conditions of the purpose. Four key process parameters–temperatures, concentration, time and extract amount were considered for the optimization of ZnO nanoparticles. XRD patterns showed that ZnO nanoparticles have hexagonal unit cell structure, SEM picture reveal the morphology and particle size of prepared ZnO nanoparticle while Fourier transform infrared spectroscopy highlighted the functional groups. The UV-VIS absorption spectrum shows an absorption band at 364nm. The optimum conditions were obtained at a temperature of 70OC, concentration of 0.75M at time 2hr and an amount of 2ml. The synthesized nanoparticles have greater potential for absorption of heavy metal ions present in water sample. These nanoparticles can be effectively used as absorbents in the commercial scale to achieve the desired goal of a clean environment.