Abstract

Sorption Mechanism Of Some Radionuclides Onto Zircono-Silicate As A Cation Exchanger

Author(s): Mamdouh M.Abou-Mesalam

Zircono-silicate as inorganic ion exchanger was synthesized in two ratio’s for Zr/Si to equal 0.4 and 1.0. Structure features for two ratio’s were conducted and the molecular formulas of two synthesized ratio’s was found, {(ZrO2)(H2SiO3)]1.58. 5.21H2O} and {(ZrO2)(H2SiO3)1.5. 7.88 H2O} for samples I and II, respectively. Distribution coefficient studies of Cs+, Co2+ and Eu3+ ions on the matrices were carried out at different reaction temperatures. Thermodynamic parameters i.e. ΔG, ΔS and ΔH have been calculated for the sorption system. The sorption process was found to be endothermic with the selectivity sequence, Eu3+ > Co2+ > Cs+ for zirconosilicate I and Co2+ > Eu3+ > Cs+ for zircono- silicate II. Kinetic studies of exchange of Cs+, Co2+ and Eu3+ ions on zircono-silicate I and II was also investigated under particle diffusion control. The effective diffusion coefficients, activation energies and entropies of activation have been evaluated.