Hg (II) Removal from Aqueous Media by Modified Mesoporous Silica SBA-15

Novel Rhodamine B thiohydrazide functionalized SBA-15 mesoporous silica is prepared, characterized and used as an adsorbent for heavy metal ion, Hg (II). The organic-inorganic hybrid mesoporous materials have been synthesized by two post-graftings of tetraethoxysilane (TEOS) with (3-Glycidoxypropyl) methyldiethoxysilane and Rhodamine B thiohydrazide in sequence. The functionalized mesoporous materials are characterized by means of X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The result indicates that, after sequent chemical modifications of glycidoxypropyl and Rhodamine B thiohydrazide, the primary hexagonally ordered mesoporous structure of SBA-15 is not affected. The mesoporous silica exhibits the excellent adsorption capacity. The removal rate of Hg2+ in aqueous media is high and the adsorbent can be regenerated by EDTA and acid treatments without changing its properties.