The thermal properties (expansion, T g and T SOFT. ) of glasses, having 56-66% P 2 O 5 , 14.8-34.2% Fe 2 O 3 and 2-25 wt% additions of SiO 2 , Al 2 O 3 , Na 2 O and UO 2 , were comparatively estimated from dilatometric measurements in similar conditions. The T g reversibility was clearly verified by varying the heating rates between 1 and 5°C min À1 . From linear equations fits of the various glass properties as functions of the six components it is suggested the iron, sodium and uranium oxides decrease the thermal expansion (for 50 < T 6 300°C), T g and T SOFT. From DTA/XRD analysis of three glasses it was confirmed the crystallization tendency decreased with increasing the UO 2 level in the glasses. Leaching test data for two compositions containing Na 2 O suggest addition of UO 2 increases the chemical durability of the related glass. The roles of UO 2 , Na 2 O and Fe-oxide species as structural components of the glass network are discussed.

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The possibility to remove cobalt cations from a simulated waste water by ferrite formation co-precipitating it with Fe +3 and Fe +2 precursors was evaluated. The incorporation of the cobalt ion to the ferrite structure was studied using different formation parameters: formation temperature, iron precursor, aging period, NaOH addition, mixing speed. The particle magnetization was increased by controlling the synthesis parameters. Two magnetic filter designs were tested to separate the ferrite from solution with an efficiency of 99% using the static fluid design.

Research reactors spent fuels disposal is a problematic area that conduces to the quest of feasible solutions for ensure safe destination of the spent fuels. In this work, a new method for processing spent fuel from MTR reactors is presenting. The main objective of this process, is the immobilization of principal radioactive elements that are present in the spent fuel, in order to achieve a suitable material which could be temporally stored safely. The Vitrocerus method involves ordinary physical procedures performed in a hot cell. It differs from conventional vitrification because there is a reduction in volume of glass material added.The process propose the ceramization of a mixture of spent fuel plates (wich were milled and calcined previously) with natural uranium oxide (U 3 O 8 ) to obtain the desired isotopic dilution (to low the U 235 enrichment). At the same time, a small fraction of VG98/12 glass [1] was added to enhance low temperature sintering. The treatment and conditioning tasks proposed in Vitrocerus were tested on MTR fuel miniplates that simulate a real U 3 Si 2 dispersed in Al fuel, which were successfully transformed into ceramic sintered pellets [2,3] with low enrichment, structural integrity, outstanding mechanical properties and water corrosion resistance. Eventually these pellets could be stored safely in an interim dry storage facility.