超低稀释比熔融制样X射线荧光光谱法测定铀矿石中主次量元素  

The determination of major and minor elements in uranium ore by Xray fluorescence spectrometry with sample preparation of ultra-low dilution fusion

作　　者：袁建[1] 孙进[1] 李博文 王娅楠 YUAN Jian;SUN Jin;LI Bowen;WANG Yanan(Beijing Research Institute of Uranium Geology,Beijing 100029,China)

机构地区：[1]核工业北京地质研究院,北京100029

出　　处：《世界核地质科学》2024年第4期817-823,共7页World Nuclear Geoscience

基　　金：国家重点研发计划“战略性矿产岩矿分析标准物质研制”(编号:2021YFC2903004)。

摘　　要：铀矿属于国家战略性矿产,目前对铀矿石的分析以化学法为主,方法成熟,标准化程度高,但操作复杂,步骤繁琐。而采用X射线荧光光谱法进行分析,样品用量大,无法用于极少量样品分析。选用四硼酸锂和偏硼酸锂混合熔剂,与样品以100∶1的超低稀释比熔融制样,利用波长色散X射线荧光光谱法测定铀矿石中Si、Al、Fe、Ca、Mg、K和U等元素。采用多个铀矿石标准物质和人工配制的工作标准制作标准曲线,理论α系数及康普顿散射内标法校正元素间的吸收增强效应,讨论了样片厚度对于样品测量的影响。方法精密度(RSD,n=10)介于0.7%~3.4%之间,且U元素方法检出限可低至15μg·g^(-1)。采用未参加回归的标准物质验证方法准确度,测量结果均在不确定度范围内。本方法通过选择有效的助熔剂和极低的稀释比,解决了X射线荧光法样品用量大,无法分析极少量样品的问题。Uranium ore belongs to the national strategic minerals resource.Uranium minerals analysis is dominated by chemical analysis,which is a well established and highly standardized but with complicated procedure.X-ray fluorescence spectrometry method need large the sample dosage and can not be used for precious sample.This paper proposed a method for the determination of the Si,Al,Fe,Ca,Mg,K,Na,U in uranium ores by wavelength dispersive X-ray Fluorescence Spectrometry using ultra low-dilution for Li2B4O7 and LiBO2 mix flux(100∶1 reagent to sample).The working curve was established by a variety of uranium ore reference materials and manual preparation working standard.The inter-element effect was corrected by using the theoretical alpha coefficient with Compton scattered radiation,we also discussed the influence of the sample thickness on the sample measurement.The results are consistent with the certified values and RSD(n=10)range from 0.7%to 3.4%,the limit detection is 15μg·g^(-1) for U.We used the reference materials which was not used in the regression to validated the method,the results were within the uncertainty.This study have solved the problem of the high dosage samples for the X-ray Fluorescence Spectrometry by selecting the effective flux and the ultra low dilution ratio.

关 键 词：铀矿石 熔融制样 X射线荧光光谱法 超低稀释比 

分 类 号：O657.34[理学—分析化学]