Removal of 2,4,6-trinitrotoluene from wastewater using a novel adsorbent polyvinyl alcohol/SiO2

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, monomer vinyl acetate (VAc) is grafted step by step on the surface of silica gel particles, and the grafted particle PVAc/SiO2 is formed. Then, the novel adsorbent polyvinyl alcohol (PVA)/SiO2 possessing strong adsorption ability for TNT is obtained through the alcoholysis reaction of PVAc. The grafted particles PVAc/SiO2 and PVAc/SiO2 are characterized by Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA). The adsorption performance of PVA/SiO2 toward 2,4,6-trinitrotoluene (TNT) is investigated through static methods. The experimental results show that PVA/SiO2 possesses strong adsorption ability for TNT with adsorption amount of 18.21 mg g(-1). The empirical Freundlich isotherm is also found to agree well with the equilibrium adsorption data. In addition, pH is found to have great influence on the adsorption amount. Finally, PVA/SiO2 is found to have excellent reusability.