CAJ | 학술논문

采用微波消解-电感耦合等离子体原子发射光谱(Inductively Coupled Plasma Atomic Emission Spectroscopy, ICP-AES)，系统研究了钍铀燃料循环后处理中4种典型稀土氟化物(NdF3、EuF3、GdF3、CeF3)在硝酸中的溶解性质。结果表明，在10 mL、浓度为16 mol·L?1的硝酸中，微波消解2 h，190oC下，4种稀土氟化物的最大溶解量可达2.5?3.9 g·L?1，均比文献报道的数值高2?3个数量级；采用ICP-AES测试溶解液，线性范围0.99947?0.99996，标准偏差SD≤4.2%(n=3)，该溶解方法旨在为核燃料后处理流程中含有难溶稀土氟化物的熔盐固溶体样品分析前处理提供参考。
채용미파소해-전감우합등리자체원자발사광보(Inductively Coupled Plasma Atomic Emission Spectroscopy, ICP-AES)，계통연구료토유연료순배후처리중4충전형희토불화물(NdF3、EuF3、GdF3、CeF3)재초산중적용해성질。결과표명，재10 mL、농도위16 mol·L?1적초산중，미파소해2 h，190oC하，4충희토불화물적최대용해량가체2.5?3.9 g·L?1，균비문헌보도적수치고2?3개수량급；채용ICP-AES측시용해액，선성범위0.99947?0.99996，표준편차SD≤4.2%(n=3)，해용해방법지재위핵연료후처리류정중함유난용희토불화물적용염고용체양품분석전처리제공삼고。
Background: A varity of rare-earth fluorides can be produced with thorium uranium fuel circulating post-processing. These fluorides need to be dissolubled in solvent for seperation and contents measurement.Purpose: This paper aims to develop a fast and efficient pretreatment method to dissolve slightly soluble rare earth fluorides in nitric acid.Methods: Rare earth fluorides related to the thorium molten salt reactor (TMSR) fuel circulating post-processing including NdF3, EuF3, GdF3 and CeF3 were studied by using Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). After 2-h microwave digestion at temperature of 190 oC, the maximum solubility of these fluorides in 10 mL nitric acid (16 mol·L?1) is determined by ICP-AES.Results: The saturated concentration varies from 2.5 g·L?1 to 3.9g·L?1, which are two or three orders of magnitude higher than their solubility reported in previous literature. The standard deviation (n=3) of measurement by ICP-AES is under 4.2% and the linear correlation coefficient (r) is in the range of 0.999 47?0.999 96.Conclusion:An efficient chemical procedure for dissolving some rare earth fluorides has been developed. It provides a reference for pretreatment of insoluble rare earth fluorides in the solid molten salt samples of thorium uranium fuel circulating post-processing.