Sorption of Cd2+ on clay mineral/hydroxyapatite nanocomposites

Abstract

In this study, the surfaces of montmorillonite (Mt) and vermiculite (Ver) were utilized as substrate for in situ preparation of hydroxyapatite (HAp) nanocomposite. Nanocomposites of clay mineral/HAp were investigated as sorbents of cadmium cations (Cd2+). Two different processes of sorption were compared-(1) dynamic and (2) static (maintaining the solutions containing Cd2+ with sorbents for 24 h in constant conditions). The samples were characterized using atomic absorption spectrometry (AAS) and X-ray powder diffraction (XRD) analysis. The results show that nanocomposites of clay mineral/HAp have higher sorption capacity than pure clays. Comparison of sorption techniques reveals small differences between sorption on Mt clay and its composites.