氟化铵消解-三乙胺增敏-电感耦合等离子体质谱法测定地球化学勘查样品中铪铌钽锆  

Determination of hafnium,niobium,tantalum and zirconium in geochemical exploration sample by inductively coupled plasma mass spectrometry with ammonium fluoride digestion and triethylamine sensitization

作　　者：刘珂珂[1] 谢亚雄[1] 苗良[1] 李果果 董学亮[1] LIU Keke;XIE Yaxiong;MIAO Liang;LI Guoguo;DONG Xueliang(High&New Technology Research Center of Henan Academy of Science,Zhengzhou 450002,China)

机构地区：[1]河南省科学院高新技术研究中心,河南郑州450002

出　　处：《冶金分析》2025年第3期17-24,共8页Metallurgical Analysis

基　　金：河南省科学院重大聚焦专项(220102002);河南省科学院成果转移转化项目(232402004)。

摘　　要：地球化学勘查样品中Hf、Nb、Ta和Zr等高场强元素的准确分析是揭示岩石成岩演化的重要前提。本文采用氟化铵固态熔融消解法与三乙胺基体改进剂增敏技术相结合,建立了电感耦合等离子体质谱法(ICP-MS)测定地球化学勘查样品中Hf、Nb、Ta和Zr的方法。样品的预处理分为两步,首先在氟化铵与样品质量比为6∶1的情况下,于240℃熔融样品2.5 h,然后添加一定量的高氯酸溶解、蒸发,加入硝酸以及少量盐酸复溶,再蒸发,可以实现样品的完全消解。将溶液蒸发至近干后,用硝酸复溶,加入2%(体积分数,下同)硝酸-0.2%氢氟酸体系为测定介质以避免Nb、Ta等元素的水解或聚合。以10%三乙胺作为基体改进剂进行测定,Hf、Nb、Ta、Zr的归一化信号强度获得了1.8、12.5、2.9以及3.3倍的增强。各元素校准曲线的线性相关系数均大于0.999,方法的检出限为2.23~22.7μg/kg,定量限为7.43~75.8μg/kg。按照实验方法对土壤、岩石、水系沉积物标准物质中Hf、Nb、Ta、Zr进行分析,每个样品平行测定12次,结果表明,测定值与认定值基本相符,测定平均值和标准值之间的对数偏差(ΔlgC)均小于0.05,相对误差(RE)为-1.7%~8.0%,相对标准偏差(RSD,n=12)为1.7%~9.0%,满足行业标准规范DZ/T 0167—2006中准确度要求。选择2个河南豫北地区土壤样品,分别按照实验方法与标准方法GB/T 14506.30—2010中氢氟酸-硝酸封闭酸溶-ICP-MS进行测定,每个样品平行测定6次,结果表明,两种方法测定结果基本一致,实验方法分析结果的相对标准偏差为1.5%~6.1%。The accurate determination of high field strength elements(HFSE)in geochemical exploration samples such as hafnium(Hf),niobium(Nb),tantalum(Ta)and zirconium(Zr)is the important prerequisite for achieving information on the diagenetic evolution of rocks.In this study,the solid melt digestion method using ammonium fluoride was combined with the sensitization technology using triethylamine as the matrix modifier.The method for the determination of Hf,Nb,Ta and Zr in geochemical exploration sample by inductively coupled plasma mass spectrometry(ICP-MS)was established.The pretreatment of sample had two steps.Firstly,the sample was melted with ammonium fluoride at 240℃for 2.5 h,where the mass ratio of ammonium fluoride and sample was 6∶1.Then,certain amount of perchloric acid were added to dissolve the sample.After evaporation,the nitric acid and a small amount of hydrochloric acid was added for redissolution-evaporation,realizing the complete digestion of sample.After evaporating the solution to almost dryness,the residue was redissolved with nitric acid.2%(volume fraction,the same below)nitric acid-0.2%hydrofluoric acid was added as the determination medium to avoid the hydrolysis or polymerization of Nb and Ta.10%triethylamine was used as matrix modifier for determination.The normalized signal intensity of Hf,Nb,Ta and Zr increased by 1.8,12.5,2.9 and 3.3 times,respectively.The linear correlation coefficients of calibration curves of elements were all higher than 0.999.The limits of detection of method were between 2.23 and 22.7μg/kg,and the limits of quantification were between 7.43 and 75.8μg/kg.The contents of Hf,Nb,Ta and Zr in certified reference materials of soil,rock and stream sediment were analyzed according to the experimental method.Each sample was determined for 12 times in parallel.The results showed that the measured values were basically consistent with the certified values.The logarithmic deviations(ΔlgC)between measurement average and standard value were all less than 0.05.The relative errors

关 键 词：氟化铵 铪 铌 钽 锆 基体改进剂 电感耦合等离子体质谱法(ICP-MS) 

分 类 号：O657.63[理学—分析化学] T03[理学—化学]