掺铀榍石人造岩石固化体的制备及其浸出性能

The Preparation and Leaching Performance of Sphene Synroc Form Doped Uranium

以碳酸钙(CaCO3)、二氧化钛(TiO2)、氧化铝(Al2O3)、氧化硅(SiO2)和硝酸铀酰(UO(2NO3)2.6H2O)为原料,采用固相反应工艺,制备掺铀榍石基人造岩石固化体。借助X射线衍射(XRD)、扫描电子显微镜(SEM)等分析手段,研究固化体的烧结温度、物相组成、U元素的浸出性能等。结果表明,掺铀榍石基人造岩石固化体的较佳烧结温度是1 260℃;榍石能很好地固溶U形成榍石固溶体;配方化学式为Ca095U0.05Ti0.9Al0.1SiO5、Ca092U0.04Ti0.9SiO5固化体,28天90℃的浸出率分别为7.0×10-10m.d-1、9.5×10-10m.d-1,其归一化浸出率分别是2.10×10-3g.m-2.d-1、1.76×10-3g.m-.2d-1。

The sphene synroc form doped uranium was prepared by solid-state method,using calcium carbonate（CaCO3）,titanium dioxide（TiO2）,alumina（Al2O3）,silica（SiO2） and uranyl nitrate [UO2（NO3）2.6H2O] as raw materials.The sintering temperatures,composes from crystals,and leaching rates of uranium of the synroc forms,were studied by means such as X-ray diffraction（XRD） and scanning electron microscope（SEM）.The results indicate that the ideal sintering temperature of the synroc form is 1 260 ℃.The sphene can dissolve commendably uranium and come into being sphene solution.The leaching rates of uranium of synroc forms,for the formulas of Ca095U0.05Ti0.9Al0.1SiO5 and Ca092U0.04Ti0.9SiO5,are 7.0×10-10 m.d-1 and 9.5×10-10 m.d-1 respectively;Their unitary leaching rates of uranium are 2.10×10-3 g.m-2.d-1 and 1.76×10-3 g.m-2.d-1 respectively at 90 ℃,42 day.