Attachment of 2-aminomethylpyridine molecule onto grafted silica gel surface and its ability in chelating cations

A route for incorporating the chelate molecule, AMP, onto silica gel was established. In the first stage a precursor silylant agent, 3-chloropropyltrimethoxysilane, is reacted with the support. The chelate molecule was then covalently bonded to the precursor surface to give 0.76 mmol of chelate per gram of silica. The immobilization reaction was confirmed through infrared spectroscopy and thermogravimetry. The anchored surface showed ability for adsorbing cations from water solution, presenting the maximum adsorption, calculated from the Langmuir equation, of: 0.84, 0.67, 0.40 and 0.22 mmol g(-1) for the divalent cations copper, cobalt, nickel and zinc, respectively. All cation/surface interactions showed favorable enthalpic and entropic values, reflected in a thermodynamic stability of the complex formed. (C) 2003 Elsevier Ltd. All rights reserved.