O 45 , corundum, periclase, and monoxide lime were detected at room temperature, while CaAl 2 O 4 and MgAl 2 O 4 spinels were ascertained at 1,200-1,400 and 1,725-1,900˚C, respectively. They were characterized using scanning electron microscopy, X-ray diffraction, X-ray fluorescence, FTIR, DTA-TGA, N 2 -gas adsorption, and laser diffraction particle size analyzer. We proved that they are chemically and thermally stable in their face-centered array spinel configurations with different surface, morphological, and topographical structures. They were used for removal of 134 Cs + , 60 Co 2+ , and 152−154 Eu 3+ from waste solutions; preliminary kinetic and pH were investigated. Langmuir, Freundlich, Dubinin-Radushkevich, Temkin, Harkins-Jura, and Halsey isothermal prototypes were applied to describe the equilibria between adsorbed phase metal ions and those in solution at different concentrations. The adsorption of 134 Cs + , 60 Co 2+ , and 152−154 Eu 3+ was critically affected by temperatures and ambient pH; spontaneous and exothermic nature of adsorption was found at specific pH values, beyond which the adsorption is restricted. The mechanism of adsorption was found to be chemical reaction combined with ion exchange rather than pure ion exchange.
