[en] Alumina, titania and silica were prepared by an advanced wet chemical method, namely sol-gel process. Characterization of the obtained gel derived metal oxide powders, through their powder morphology using a scanning electron microscope (SEM), BET surface area measurements, simultaneous DTA and TG measurements, and X-ray diffraction analysis were performed. These measurements proved that the gel derived metal oxide powders produced by hydrolysis of metal alkoxides are of a very high reactivity, homogeneity, and fine particle size. The uptake behavior of the fabricated sol-gel powders for radioactive Eu (III) was studied. The experimental results showed that Eu (III) uptake on the prepared ceramic powders were of the order titania > alumina> silica. In addition the stability of these ceramic powders for Eu (III) uptake was examined through a desorption process of the adsorbed ions by distilled water. The desorption process proved also the stability of the materials used for Eu (III) uptake. 12 figs., 2 tabs

[en] Fly ash-zeolite cement was synthesized from industrial by-product fly ash obtained from the thermal electric power station. The synthesis process is based on the hydrothermal-calcination-route of the fly ash. The microstructure of fly ash-zeolite cement was characterized by X-ray diffraction, FT infrared spectroscopy and surface area (F-N₂). The efficiency of innovative matrices for immobilizing cesium and cobalt radionuclides is presented in this work. The aim of the present study is to investigate the possibility of solidifying ¹³⁷Cs and ⁶⁰Co radionuclides in synthetic fly ash zeolite cement. Leaching behavior of the radionuclides have been studied. The leachability index measured indicated that fly ash zeolite cement matrix can be utilized as an efficient material for immobilizing cesium and cobalt radionuclides than portland cement.