含Ca_(3)(PO_(4))_(2)模拟废物铁磷酸盐玻璃固化体的析晶行为和抗浸出性能  

Crystallization Behavior and Anti-Leaching Performanceof Iron Phosphate Glass Solidified WasteformsContaining Ca_(3)(PO_(4))_(2) Simulated Waste

作　　者：张琳 常煚 杨明帅 王佳腾 谭盛恒 何辉[1] ZHANG Lin;CHANG Jiong;YANG Ming-shuai;WANG Jia-teng;TAN Sheng-heng;HE Hui(Department of Radiochemistry,China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院核化学与放射化学研究所,北京102413

出　　处：《核化学与放射化学》2025年第2期133-141,I0002,共10页Journal of Nuclear and Radiochemistry

摘　　要：磷酸三丁酯/煤油(TBP/OK)悬浊液或乳化液经高温氧化处理后,计算发现产物放射性水平可达中高放废物水平,若直接排放或处理不当,会产生放射性环境污染问题。本工作基于(37-x)(摩尔分数,%,下同)Fe_(2)O_(3)-xB_(2)O_(3)-56P_(2)O_(5)-7Na_(2)O四元铁磷酸盐玻璃作为固化基体,进行氧化产物玻璃固化实验,研究了铁磷酸盐玻璃配方固化目标废物的影响,通过X射线衍射(XRD)、差热分析、扫描电子显微镜-能量色散X射线光谱(SEM-EDS)的综合分析发现,B_(2)O_(3)摩尔分数为0~3%的样品析晶倾向、致密度、玻璃体均一性及相关元素的浸出性明显差于B_(2)O_(3)摩尔分数为5%~10%的玻璃样品。PCT-B浸出实验发现,随着B_(2)O_(3)摩尔分数的增大,玻璃固化体中B、Na、Cs、Sr的浸出无明显变化,质量损失遵循NLP、B、Cs、Na、Ca>>NL_(Sr)>>NL_(La)>>NL_(Fe)的规律,所有元素的归一化质量损失均小于10^(-2) g/m^(2),化学稳定性较好,可作为适用于模拟氧化产物的玻璃固化配方。Radioactive TBP/OK organic liquid waste is generated during the processes of uranium purification and spent fuel reprocessing.After high-temperature oxidation treatment,the main products of this waste liquid are calcium phosphate and pyrophosphate.The waste also contains volatile radioactive nuclides such as cesium,as well as alpha-emitting nuclides like uranium(U)and plutonium(Pu).If discharged directly or improperly treated,this waste liquid may cause radioactive environmental pollution,which can severely impact ecological health and human health.Therefore,it is essential to use appropriate methods to solidify the cracked products to safely manage and dispose of the secondary waste generated from TBP cracking.Borosilicate glass shows limited tolerance for waste containing large amounts of phosphates,iron oxides,and some heavy metal nuclides(such as La,U,and Bi).In recent years,iron phosphate glass has attracted widespread attention and in-depth research due to its good tolerance for phosphates,sulfates,iron oxides,and other heavy metal elements in high-level radioactive waste,as well as its good stability.The O-P-O bonds in the structure of iron phosphate glass are replaced by more stable FeP-O bonds,resulting in a large number of stable Fe-P-O bonds in the glass.Additionally,iron phosphate glass has a lower melting temperature.In this study,a quaternary iron phosphate glass with the composition(37-x)(mole fraction,%,the same below)Fe_(2)O_(3)-xB_(2)O_(3)-56P_(2)O_(5)-7Na_(2)O was used as the vitrification matrix to conduct glass solidification expenments on simulated waste.The experiments investigated the effects of different simulated waste contents and varying B_(2)O_(3) contents on the crystallization behavior and chemical stability of the iron phosphate glass solidified bodies.Through comprehensive analysis using X-ray diffraction(XRD),differential thermal analysis,and scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDS),it was found that this formulation can tolerate up to 35%(mass f

关 键 词：铁磷酸盐玻璃 玻璃固化 中高放废物 

分 类 号：TL941.11[核科学技术—辐射防护及环境保护]