Abstract
World Health Organisation (WHO) classifies heavy metals as persistent toxic substances having acute toxicity and accumulation effects to the environment, and humans as well. Lack of adequate treatment of such metals from water streams has led to water resource contamination across the country resulting in unfavorable biological and environmental effects. In ensuring the safety of drinking water, proper techniques for the preconcentration and determination of such toxic metals from drinking water are required. In this study, the magnetic polyurethane foam nanocomposite was successfully fabricated using the co-precipitation and polymerization method. Various techniques such as XRD, FTIR, SEM, TEM, EDS, BET, TGA, and Zeta potential were used to characterize the nanocomposite. The formation of this material was confirmed by XRD, TEM, and FTIR through phase identification, morphological analysis, and chemical composition. EDS further corroborated the formation of the nanocomposite by showing elements composed of the material. TGA showed the thermal stability of the material, furthermore, BET and Zeta potential were able to demonstrate the physical properties of the material with a surface area of 7.6462 m2/g and surface charge of 2.00, respectively. This material was further used as an adsorbent and tested for the preconcentration and determination of two trace metal ions, Cd (II) and Pb (II) from drinking water. Before the analysis of the water samples by IC-OES, the developed magnetic solidphase extraction was optimized using a central composite design. Under optimum conditions, the percentage recovery ranging from 76.4-98.6 % was obtained. The LODs and LOQs ranged from 0.024-0.029 μg L1 and 0.08-0.096 μg L1, respectively. The linearity ranged from 0.1 to 600 μg L−1 with the correlation of coefficients (R2) ranging from 0.9875 to 0.9927. The %RSD that estimates the precision of the developed magnetic solid-phase method of less than 5% for both trace metal ions was achieved. The PUF-IONPs nanocomposite demonstrated the properties of being a potential adsorbent that can be used in the preconcentration of Cd (II) and Pb (II) ions from drinking water.
M.Sc. (Nanosciences)