Adsorption Properties Of Hydrous Titanium-Zirconium Mixed Oxide Heated To Different Temperatures KEYWORDSAuthor(s): N.A.Tadrous, T.N.Morcos, S.I.M.Moussa
Hydrous oxides as well as mixed oxides are promising materials, among other types of inorganic ion-exchangers, for the removal of radioactive elements from waste solutions. Characterization, ion exchange property, thermal stability were studied for two synthetic hydrous titanium-zirconium mixed oxides. These oxides mainly consist of metal ions having both large(titanium), small(zirconium) ionic potential. The structural features, surface area , thermal stability of the prepared samples were investigated through the study of their physicochemical properties using appropriate techniques such as IR, X-ray, thermal analyses(TGA & DTA), surface area by nitrogen adsorption(BET). The results of the physicochemical properties prove that both the prepared samples are virtually amorphous, posses high surface areas with a large number of exchange sites(OH , H2O). These exchangers possess a high cation exchange capacity, are expected to be anion exchangers since hydrous zirconium oxide has an amphoteric character. Equilibria measurements showed high affinity to Cs+, Co2+, Zn2+, Eu3+. Thermal stability of the hydrous oxides indicated high resistance towards high temperatures up to 4000C where the oxide retained some of its capacity, especially in case of Eu3+. The exchange sites available at relatively high temperature are probably surface H2O groups.