Silica-gel-based adsorbents (SG-DETA and SG-DETA2) grafting of dendrimer-like highly branched polymer
were prepared by an improved methods of a combination of homogeneous and heterogeneous. FTIR
analysis, SEM analysis, pore structure analysis and thermodynamic analysis manifested that dendrimerlike
highly branched polymer was successfully grafted onto the silica surface. The results of the adsorption
thermodynamics and kinetics of the as-synthesized SG-DETA and SG-DETA2 showed the adsorbents
had good adsorption capacity for Au(III), and the best interpretation for the experimental data was given
by the Langmuir isotherm equation. The maximum adsorption capacity for Au(III) were 2.09 and
2.12 mmol g1 of SG-DETA and SG-DETA2 at 35 C, respectively. Moreover, the study indicated the
adsorption kinetics of SG-DETA and SG-DETA2 could be modeled by the pseudo-second-order rate equation
wonderfully. The SG-DETA and SG-DETA2 adsorbents had excellent adsorption selectivity for Au(III)
in binary metal solution systems. Therefore, the high adsorption capacity make these adsorbents have
significant potential for Au(III) uptake from aqueous solutions using adsorption method.
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