Adsorption mechanism and property of a novel adsorption material PAM/SiO2 towards 2,4,6-trinitrotoluene

2,4,6-Trinitrotoluene (TNT) is toxic and mutagenic to many living organisms, so more and more rigorous limits on the letting amount of TNT have been established. In this paper, functional monomer acrylamide (AM) was grafted step by step on the surface of silica gel particles, and the grafted particle PAM/SiO2 with strong adsorption ability for TNT was formed. The adsorption mechanism and properties of PAM/SiO2 for TNT were researched through static and dynamic methods. The experimental results showed that PAM/SiCO2 possesses strong adsorption ability for TNT with interaction of three kinds of hydrogen bonds including peculiar N-H...pi hydrogen bond (aromatic hydrogen bond) and C-H...O=C pi hydrogen bond. The saturated adsorption amount could reach to 0.873 m g g(-1). The empirical Freundlich isotherm was found to describe well the equilibrium adsorption data. In addition, the pH and temperature were found to have great influence on the adsorption amount. Mixture solution of HCl and ethanol is used as eluent, and the adsorbed TNT is eluted easily from PAM/SiO2. Finally, PAM/SiO2 was found to have excellent reusability. (C) 2009 Elsevier B.V. All rights reserved.