Adsorption of Pb2+ on amino-functionalized core-shell magnetic mesoporous SBA-15 silica composite

Magnetic mesoporous SBA-15 microspheres were fabricated by a colloidal chemical method. The prepared microspheres were hydrated with steam at 40 degrees C and then functionalized with aminopropyltriethoxysilane, resulting in a large amount of amino groups (2.77 mmol/g) grafted on the microspheres with ordered mesostructure. The amino-functionalized magnetic mesoporous composite showed excellent adsorptive capability toward heavy metal ions and the adsorption capacity was as high as 243.9 mg/g for Pb2+ at room temperature. The adsorbent could be easily removed from solution by an external magnetic field and regenerated easily by acid treatment. These results suggest that this kind of composite is potentially useful for effectively adsorbing heavy metal ions in aqueous solution. (C) 2014 Elsevier B.V. All rights reserved.