Intensively competitive adsorption for heavy metal ions by PAMAM-SBA-15 and EDTA-PAMAM-SBA-15 inorganic-organic hybrid materials

EDTA modified Gn-PAMAM-SBA-15 (n = 1, 2, 3 and 4) inorganic-organic hybrid materials were successfully prepared with the structures characterized by XRD, FT-IR spectra and CP-MAS (CNMR)-C-13. The adsorption characters of the Gn-PAMAM-SBA-15 and EDTA modified materials were studied. The G3- and G4-PAMAM-SBA-15 samples showed high selectivities for Cr3+, Pb2+ and Zn2+ with the distribution coefficients K-d values larger than 1.25 x 10(4). When the EDTA modified adsorbents were chosen, the K-d for the Cu2+ and Ni2+ were increased. The metal loaded Gn-PAMAM-SBA-15 and EDTA modified samples may be regenerated. (c) 2007 Elsevier Inc. All rights reserved.