Preparation of Bifunctional Polysilsesquioxane/Carbon Nanotube Magnetic Composites and Their Adsorption Properties for Au (III)

Abstract Bifunctional polysilsesquioxane/carbon nanotube magnetic composites were prepared by coating the polysilsesquioxane with amino and thiol groups on carboxyl carbon nanotubes (CNTs-COOH) embedded with magnetic ferroferric oxide (Fe3O4). The morphology and physicochemical properties of the composites were characterized by FT-IR, SEM, VSM, XRD, XPS and BET, and the adsorption capacities of these composites for Au(III) was investigated systematically. The thermodynamic adsorption curves conform to the Langmuir model, and the kinetics curves can be fitted to the pseudo-second-order model. The adsorption capacities of the composites for Au(III) at 35 ℃ varied from 2.01 mmol/g to 2.82 mmol/g according to the Langmuir model. Selective adsorption tests showed that the bifunctional composites could selectively adsorb Au(III) in a number of binary metal ions systems. It is expected that the bifunctional polysilsesquioxane/carbon nanotube magnetic composites can be used to recover low concentration Au(III) from waste water.