Al2O3 nanoparticles synthesized using various oxidizing agents: Defluoridation performance

Abstract This study concerns the removal of fluoride using aluminium oxide nanoparticles synthesized in the presence of oxidizing agents H 2 SO 4 , KMnO 4 and K 2 Cr 2 O 7 . The obtained nanoparticles were characterized using TGA, FESEM, EDX and XRD. The almost constant weight loss was observed from the TGA data for the temperature range from 400 to 650 °C. XRD analysis with and without oxidizing agents indicated the crystalline behaviour which increased with increasing the temperature. Prepared Al 2 O 3 nanoparticles exhibited a considerable potential for fluoride adsorption from an aqueous medium in the concentration range of 2–8 mg/l. In this case, around 92% fluoride was adsorbed at pH = 4.7. The equilibrium data were well fitted with Freundlich adsorption isotherm, whereas the adsorption kinetic data followed the pseudo second order model.