Equilibrium And Kinetic Studies About Sorption Of Uranium(Vi) Using The Cross-Linking Chitosan Submicron Particles Modified By Ammonium Fluotitanate

The cross-linking chitosan submicron particles modified by ammonium fluotitanate (Ti/CTS) was obtained and used as a new low-cost adsorbent for radioactive uranyl ion from aqueous solutions. The prepared adsorbent was characterized by Fourier transform infrared spectroscopy, scanning electron microscope, Brunauer-Emmett-Teller, and X-ray diffraction. In addition, measurements and effects of the initial pH, contact time, adsorbent dosage, initial concentration of U(VI), and temperature on the adsorption of U(VI) ions were studied in detail. The results indicated that the Ti/CTS exhibited excellent adsorption properties. The maximum adsorption capacity of Ti/CTS was 195 mg g(-1). It was found that the adsorption equilibrium data could be best fitted to the pseudo-second-order model. In the meantime, the intraparticle diffusion model and Elovich model were also used to study the adsorption dynamics. The Langmuir isotherm model could be used to describe the adsorption process and the thermodynamic parameters Gibbs free energy (Delta G degrees), standard enthalpy change (Delta H degrees), and standard entropy change (Delta S degrees) for the process were calculated. Furthermore, the Ti/CTS could be regenerated through desorption of the uranium and could be reused for adsorption.