Materials Chemistry and Physics, Vol.178, 57-64, 2016
An insight into the removal of Cu (II) and Pb (II) by aminopropyl-modified mesoporous carbon CMK-3: Adsorption capacity and mechanism
In this study, the adsorption of heavy metal ions onto ordered mesoporous carbon CMK-3 was investigated. CMK-3 has been synthesized using SBA-15 as the hard template and then directly amino-functionalized by the treatment with 3-aminopropyltrimethoxysilane (APTMS) without the need of oxidation before. The thus obtained modified mesoporous carbon has been characterized by nitrogen sorption, X-ray diffraction and infrared spectroscopy. Its adsorption efficiency for the removal of Cu2+ and Pb2+ from aqueous solutions was tested. The effects of contact time, pH and initial metal ions concentration were investigated as well. The adsorption capacities were very high (3.5 mmol g(-1) and 8.6 mmol g(-1) for Pb2+ and Cu2+ respectively). These values depend largely on the speciation of metal ions as a function of pH. The selectivity was also dependent on the nature of metal ions rather than the adsorbent used. The mechanism of adsorption is complex where several types of interaction between metal ions and the adsorbent surface are involved. (C) 2016 Elsevier B.V. All rights reserved.