Thermodynamics Study for the Sorption of <SUP>134</SUP>Cs and <SUP>60</SUP>Co Radionuclides from Aqueous Solutions

Abstract

The removal of cesium and cobalt radionuclides from aqueous chloride solutions using hydrous titanium oxide was investigated. The influence of initial ion concentration, pH, and temperature has been reported. The data obtained have been correlated with Langumir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm models. The effect of temperature on the equilibrium distribution values has been investigated. The thermodynamic parameters such as free energy (∆G o ), enthalpy (∆H o ) and entropy (∆S o ) have been calculated. Maximum ion exchange capacity and the mean free energy of each studied ion have been determined using D-R isotherm model.

Sorption of 137Cs and 60Co on Titanium Oxide Films in Light Water Reactor Primary Circuit Environment

“…Venkataramani [7] has found that sorption of 137 Cs on hydrated titanium dioxide becomes noticeable at pH 4 and increases significantly upon transfer to alkaline medium-at pH 10 sorption is more than 10 times higher than at pH 4. Metwally [8] studied thermodynamic parameters of caesium ion sorption onto titanium dioxide. According to his data, upon the increase of temperature Gibbs free energy of the sorption process decreases, which makes this process more favorable from a thermodynamic point of view-reaction ability of titanium dioxide increases, and after the temperature rises from 25 to 50 • C, the amount of caesium sorped approximately increases twofold.…”

“…Bignon [1] only studied the composition of film and not its contamination with radionuclides. Some authors [6][7][8][9][10][11] studied sorption of cobalt and caesium radionuclides but either freshly precipitated hydrated titanium dioxide or nanocomposites from hydrated and non-hydrated titanium dioxide were used as sorbents. At the same time, freshly precipitated hydrated titanium dioxide has a large specific surface area (ca.…”

“…At the same time, freshly precipitated hydrated titanium dioxide has a large specific surface area (ca. 200 m 2 /g [14,15]) and a significant amount of hydroxyl groups on its surface (2-5 nm −2 [8]). As a result, the level of radioactive contamination and factors determined its values for hydrated titanium dioxide, and the oxide film on titanium alloys should differ significantly.…”