电感耦合等离子体原子发射光谱法测定铀锆合金中钙锂镁钠

铀锆合金燃料中的杂质元素会影响其运行的安全性,准确测定Ca、Li、Mg、Na元素的含量具有重要意义。先使用硝酸-氢氟酸溶解样品,再采用UTEVA萃淋树脂,在酸性介质中使铀基体与待测元素定量分离,选择Ca 422.673nm、Li 670.784nm、Mg 279.553nm、Na 589.592nm作为分析谱线,建立了电感耦合等离子体原子发射光谱法(ICP-AES)测定铀锆合金中Ca、Li、Mg、Na的分析方法。使用1mol/L硝酸淋洗UTEVA萃淋色谱柱,这一分离流程对铀的去污因子约为4.0×10⁴。Ca、Li、Mg、Na的出峰体积在6~10mL,因此保留10mL淋洗液可以满足Ca、Li、Mg、Na的测定要求。Ca、Li、Mg、Na的质量浓度为0.025~0.50mg/L时与其发射强度呈线性关系,线性相关系数均不小于0.9990;方法检出限为0.1~1.0mg/kg。按照实验方法测定铀锆合金中Ca、Li、Mg、Na,测定结果的相对标准偏差(RSD,n=6)小于3%;回收率为90%~105%。

Determination of calcium,lithium, magnesium and sodium in uranium-zirconium alloy by inductively coupled plasma atomic emission spectrometry

The impurity elements in uranium-zirconium alloy fuel influence the safety of operation. Therefore, it is of great significance to accurately determine the contents of Ca, Li, Mg and Na. The samples were firstly dissolved with nitric acid-hydrofluoric acid. The uranium matrix was quantitatively separated from testing elements in acid medium using UTEVA extraction resin. Ca 422.673nm, Li 670.784nm, Mg 279.553nm and Na 589.592 nm were selected as the analytical lines. The analysis method of Ca, Li, Mg and Na in uranium-zirconium alloy by inductively coupled plasma atomic emission spectrometry (ICP-AES) was established. UTEVA extraction chromatographic column was leached with 1mol/L nitric acid. The decontamination factor of uranium in this separation process was about 4.0×10⁴. The peaking volume of Ca, Li, Mg and Na was in range of 6-10mL, so 10mL of eluent could meet the determination requirements of Ca, Li, Mg and Na. The mass concentration of Ca, Li, Mg and Na in range of 0.025-0.50mg/L had linearity relationship with the corresponding emission intensity, and the linear correlation coefficients were all higher than 0.9990. The limit of detection was between 0.1 and 1.0mg/kg. The contents of Ca, Li, Mg and Na in uranium-zirconium alloy were determined according to the experimental method. The relative standard deviations (RSD, n=6) of determination results were less than 3%. The recoveries were between 90% and 105%.