Adsorption of 137Cs on titanate nanostructures

Various types of sodium and potassium titanate nanostructures (nanotubes, nanofibers, nanoribbons, nanowires) were synthesized and characterized by X-ray diffraction, SEM and TEM, as well BET and BJH methods. Adsorption of radiotracer 137Cs+ ions from aqueous solutions on synthesized titanate nanostructures was investigated in batch technique as a function of contact time, concentration of sodium ions and pH of the solutions. It was found that among the studied nanostructures nanotubes shows the highest selectivity for 137Cs, which is related to a zeolitic character of Cs+ adsorption. The efficient adsorption of 137Cs was obtained in Na+ solutions with concentration below 10-2 M, at pH 7-9 and in contact time above 2 h. Moreover, nanotubes have the higher specific surface area than other nanostructures, which results in better availability of ion exchange groups and high ion exchange capacity. These properties of nanotubes indicate that they may be used for adsorption of 137Cs from various types of nuclear wastes. (author)