Removal of simulated radionuclide Ce(III) from aqueous solution by as-synthesized chrysotile nanotubes

Abstract

Chrysotile nanotubes (ChNTs) were synthesized under hydrothermal conditions for removing simulated radionuclide Ce(III). The prepared samples were characterized by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM) and N2 adsorption and desorption which show that as-synthesized ChNTs possess hollow structured, whose inner and outer diameters are ca. 8–15nm and 30–50nm respectively with inner aspect ratio to 20. The BET surface area and total pore volume were calculated to be 144.1m2g−1 and 0.39cm3g−1, respectively. In addition, the effects of contact time, solid content, pH and temperature were also investigated by batch technique. The adsorption kinetics and isotherms of ChNTs for Ce(III) indicate that the kinetic adsorption is well described by the pseudo-second-order model and the adsorption isotherm is fitted well by Langmuir model (Qmax=1.21×10−3molg−1 at 348±1K). The thermodynamic parameters (i.e., ΔG∘, ΔS∘ and ΔH∘) of the adsorption for Ce(III) were determined from the temperature dependent adsorption isotherms at 298, 323 and 348±1K, respectively. The results indicate that the adsorption process of Ce(III) on ChNTs is spontaneous and endothermic.