| The object of this research is 238U nuclide, by using the assemblage of zirconolite and sphene to do the research of crystal lattice immobilization that contains uranium waste systematically, it proves that zirconolite and sphene crystal lattice solidification have well properties. Using natural zirconite,calcium carbonate,rutile and nitric acid uranium acyl as raw materials, the crystal lattice solidification loaded with UO2 4.9wt%,9.84wt%,14.70wt%,19.53wt% and 24.32wt% respectively are fabricated by high temperature solid phase reaction in the experiment. The phase assemblages of solidification, microstructures, phase chemical assemblages and chemical durability etc are analyzed by means of XRD,SEM/EDS and MCC-1 leaching test. The result of the research shows that the quantity of the mixed uranium has a little effect on the aim mineral phase systemization and sinter temperature of solidification and the lowest synthesize temperature of different formulae is 1200℃, the best sinter temperature of different loaded capability solidification is 1290℃. During the sinter of 1290℃, solid phase reaction in solidification is completed, mineral phase combine is compact and the structure of crystal is fast. The fabricated solidification in this temperate had good physical properties with high density(> 3.9g/cm3), few porosities(>3%) and high shrinkage rate(>12%). The entire element in the distribution of solidification is uniform and there is no distinct conglomeration exists. U4+ mainly incorporate in Zr site of zirconolite and when the loading of solidification is excessive, up to 0.5 formula unit of U4+ incorporated in the Zr site in local area, reaction products produce pyrochlore phase. The MCC-1 tests show all the samples are highly durable and low leaching rate, the accumulative leaching rate and the unitary leaching rate of u nuclide is less than 1×10-8cm/d , 1×10-6cm and 2×10-4g/m2?d respectively. All the dates are lower 2-3 order of magnitude than glass waste form.
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