Kinetic aspects and swelling changes of magnesium and cerium titano-antimonates in aqueous and mixed solvents

Magnesium titano-antimonate (MgTi₅Sb₂O₁₆·12.5H₂O) and cerium titano-antimonate (Ce₂.₇Ti₅Sb₂O₁₉·15.0H₂O) were synthesized as new cation exchangers using the in situ precipitation technique. Physico-chemical investigations showed different behaviors for the obtained materials. The materials have significant stability at high acid concentration and temperature. The ion exchange capacity for Cs⁺ in the presence of different alcoholic solvents was found to increase and generally obey the order C₂H₅OH > CH₃OH > H₂O. Diffusion coefficients (D_i) and thermodynamic parameters of Cs⁺ exchange in both magnesium and cerium titano-antimonates in aqueous and alcoholic solutions were calculated. The swelling ratios of the materials were predicted by applying modified calculations at constant values of D_i. The results showed insignificant swelling behavior in the presence of organic solvents.