Chelating agent-free solid phase extraction (CAF-SPE) of uranium, cadmium and lead by Fe-Al-Mn nanocomposite from aqueous solution

Fe-Al-Mn nanocomposite has been synthesized by impregnating MnO2 with Fe and Al nitrate aqueous solution for preconcentration and determination of Pb (II), Cd (II) and U (VI) ions from aqueous solution. Fourier Transform Infrared spectroscopy (FTIR), X-Ray-diffraction (XRD) and Scanning electron microscopy coupled with energy dispersive X-ray detector (SEM-EDX) were employed to characterize the as-synthesized nanocomposite. The XRD result indicates that the as-synthesized nanocomposite had a crystal size with rhombohedral structure and size of 30.81 nm. FTIR results confirmed the presence of hydroxyl group and Metal-Oxygen vibration in the adsorbent. A sensitive and simple solid-phase preconcentration procedure for the determination of trace amounts of Pb(II) and Cd(II) ions by FAAS and U(VI) ions by Uv-Vis was developed. The adsorption isotherm was formally described by both Langmuir and Freundlich equation with a maximum adsorption capacity of 12.5 (Pb), 12.8(Cd) and 14.9(U) mg g(-1) respectively with preconcentration factor of 15. The limits of detection were 0.09, 0.05 and 0.0097 mg L-1 and the relative standard deviation for ten replicate measurements were 2.47, 0.979 and 2.04%, for Pb (II), Cd(II) and U(VI) ions, respectively. The recovery of Pb(II), Cd(II) and U(VI) ions were found to be 92.7, 91.3, and 81.76%, respectively. On the basis of these findings, the as-synthesized Fe-Al-Mn nanocomposite was successfully applied as a solid phase extraction for preconcentration and determination of Pb(II), Cd(II) and U(VI) ions in aqueous solution.

Automated summary

Fe-Al-Mn nanocomposite was synthesized and used for preconcentration and determination of Pb(II), Cd(II), and U(VI) ions in aqueous solution. The as-synthesized nanocomposite had a rhombohedral structure with a crystal size of 30.81 nm. A sensitive solid-phase preconcentration procedure using FAAS and Uv-Vis was developed, with a maximum adsorption capacity of 12.5 (Pb), 12.8 (Cd), and 14.9 (U) mg g(-1), and a preconcentration factor of 15. The method showed low detection limits and good precision. The nanocomposite exhibited high recovery rates for Pb(II), Cd(II), and U(VI) ions. The Fe-Al-Mn nanocomposite is considered to be a promising solid phase extraction material with potential applications.