Abstract
In this paper, Al2O3 nanoparticles with an average crystallite size of 35.56 nm are facilely synthesised using the combustion procedure in the presence of glutamine as organic fuel. Besides, Al2O3/Sodium dodecyl sulphate/2-aminophenol composite is synthesised and applied as a novel adsorbent for the removal of Pb(II), Cd(II), and Co(II) ions from aqueous media. The synthesised samples are characterised using several tools such as X-ray diffraction (XRD), elemental analysis, Fourier-transform infrared spectroscopy (FT-IR), and field emission scanning electron microscopy (FE-SEM). In the case of Al2O3, the XRD peaks, which were appeared at 2 theta of 38.11, 46.21, and 66.72 degrees, are attributed to the (311), (400), and (440) planes of gamma-Al2O3, respectively. In the case of Al2O3/Sodium dodecyl sulphate/2-aminophenol composite, the existence of a wide XRD peak at 2 = 25 degrees confirming that the crystal assembly of Al2O3 combined or interfered over amorphous organic surroundings. Elemental analysis of the Al2O3/Sodium dodecyl sulphate/2-aminophenol composite displayed that the % C, % H, and % N are 17.23, 4.21, and 1.58%, respectively. The maximum adsorption capacity, which was obtained from Langmuir isotherm, of the composite towards Pb(II), Cd(II), and Co(II) ions is 119.19, 101.21, and 86.51 mg/g, respectively. The best description for the experimental results is given by the pseudo-second-order kinetic model and Langmuir adsorption isotherm. Also, the thermodynamic parameters confirmed that the removal of studied ions is spontaneous, exothermic, and chemical. After three adsorption-desorption cycles, 25%V/V (Methanol/HNO3) is the suitable desorbing medium needed for the recapture of the adsorbed metal ions on the composite. Hence, the synthesised composite could be reutilised without notable losses of its effectiveness.