ICP—MS同时测定地球化学样品中的铌钽

Simultaneous Determination of Nb and Ta in Geochemical Samples by Inductively Coupled Plasma Mass Spectrometry

建立了测定地球化学样品中铌、钽元素的ICP—MS方法。试样加入硝酸、氢氟酸、高氯酸，于电热板上加热消解样品，再以新配置王水提取，使铌、钽完全进入溶液，以内标法校正干扰，电感耦合等离子体质谱仪（ICP—MS）测定样品消解液中铌、钽元素。其中铌采用铑元素作为内标，以93质量数分析；钽采用铼元素作为内标，以181质量数分析。方法的检出限为Nb0．02μg/g，Ta0．01μg/g精密度优于5％。整个方法检出限低、简单、快速和准确。经过国家一级地球化学标准物质的分析验证，结果与标准值吻合，方法已应用于国土资源调查的试样分析。

An analytical method for the determination of niobium （Nb） and tantalum （Ta） in geochemical samples by inductively coupled plasma mass spectrometry （ICP -MS） was developed. The samples were digested on electrical hot plate by mixed acid consisted of nitric acid, hydrofluoric acid and perchloric acid. After digestion newly - prepared aqua regia was added to ensure the complete dissolution of Nb and Ta. Internal standards were adopted for the interference correction of ICP-MS analysis,among which Rh93 and Rel81 were selected as internal standard elements of Nb and Ta respectively. The limits of detection for Nb and Ta were 0.02 ug·g-1 and 0.01 ug·g-1respectively with the relative standard deviation （RSD） better than 5%. The method was validated by the analysis of primary geochemical reference materials, with all of its results consistent with standard values, which was then applied to analyze land and resource survey samples, and was proved to be simple, sensitive and accurate.