Cyclic ligand functionalized mesoporous silica (SBA-15) for selective adsorption of Co2+ ion from artificial seawater.

Hard donor atoms (N and O) containing macrocyclic ligand was synthesized and further functionalized with mesoporous SBA-15 materials by chemical modification method. The modification was achieved by the immobilization of 3-chloropropyltriethoxysilane (CIPTES) onto mesoporous silica surface followed by post grafting route. The resulting material (Py-Cy-SBA-15) has been characterized by low angle X-ray diffraction (XRD), nitrogen adsorption-desorption isotherm, Fourier-transform infrared (FT-IR) spectroscopy, 29Si and 13C CP MAS NMR spectroscopic analyses, Thermogravimetric analysis (TGA) and elemental analysis. The long range orders of the materials were identified by transmission electron microscopy (TEM). The functionalized material was employed to the heavy metal ions adsorption from aqueous solution containing Cu2+, Co2+, Zn2+, Cd2+ and Cr2+. The prepared hybrid material showed high selectivity and adsorption capacity for Co2+ ion at pH 8.0.