UO_(2)在碳酸盐熔盐中的反应行为研究

Research on the reaction behavior of UO_(2)in molten carbonate

为获得UO_(2)在碱金属碳酸盐熔盐体系中的基础反应数据,本文分析了UO_(2)在不同组分碳酸盐熔盐中的平衡浓度和反应产物。本文借助电感耦合等离子体质谱、X射线衍射、红外光谱等表征方法,研究反应产物及铀的形态。结果表明:在本文条件下,铀元素在不同组分碳酸盐熔盐中平衡浓度(500~700℃)呈“V”型分布,其平衡浓度在20~220μg/g,最小值在二元和三元熔盐体系中分别低于30μg/g和60μg/g(600℃)。另外UO_(2)在碳酸盐熔盐中的反应产物结构均以重铀酸盐为主(<700℃)。在碳酸盐熔盐体系中系统的分析了UO_(2)的反应行为,验证了碳酸盐盐熔盐氧化技术对UO_(2)进行氧化处理的可行性,为该技术的发展提供了一定基础数据的支撑。

To obtain basic reaction data for UO_(2)in an alkali metal molten carbonate system,we investigated the equilibrium concentration and reaction behavior of UO_(2)in molten carbonate using inductively coupled plasma mass spectrometry,X-ray diffraction,infrared spectroscopy and some other characterization methods.The results show that the equilibrium concentrations of uranium under the above conditions exhibited a“V”shaped distribution in the temperature range of 500~700℃,which were in the range of 20~220μg/g.The minimum uranium concen-tration was below 30 and 60μg/g(at 600℃)in the binary and ternary molten salt systems,respectively.The UO_(2)reaction products in molten carbonate were mainly diuranates(<700℃).The reaction behavior of UO_(2)in the molten carbonate system was systematically analyzed to verify the feasibility of oxidizing UO_(2)using molten carbonate oxidation technology,which provides basic data to support the development of this technology.