电感耦合等离子体串联质谱法同时测定土壤和水系沉积物中关键矿产稀散元素镓铟锗硒碲

Simultaneous Quantification of Critical Mineral Elements Gallium, Indium, Germanium, Selenium, and Tellurium in Soils and Stream Sediments by Inductively Coupled Plasma-Tandem Mass Spectrometry

  • 摘要: 镓、铟、锗、硒、碲在地壳中的丰度极低且分布稀散,因在清洁能源转型中的关键应用而被列入关键矿产。传统分析方法受制于其质谱响应弱及严重干扰(尤其是元素硒),需分别采用电感耦合等离子体质谱(ICP-MS)和氢化物发生原子荧光光谱(HG-AFS)两种技术而无法实现一次溶样、同时测定。本文采用硝酸-氢氟酸-高氯酸常压敞口消解体系,在保证样品充分消解的同时有效避免了锗和硒的挥发损失;质谱测量中通过引入异丙醇(2%,V/V)作为增敏剂提升了硒(80Se)和碲(128Te)的质谱响应,增强倍数分别达2.75倍和2.32倍;采用氧气(O2)作为反应气的ICP-MS/MS质量转移模式(80Se+96SeO+),有效消除了80Se的严重质谱干扰,使硒的定量信噪比提升至58.20。由此建立了电感耦合等离子体串联质谱(ICP-MS/MS)同时测定土壤和水系沉积物中5种关键矿产元素镓铟锗硒碲的分析方法。方法检出限为0.002~0.060 μg/g,6件土壤和水系沉积物国家一级标准物质的ΔlgC值均在±0.05以内,且相对标准偏差(RSD)均<5%。本方法解决了锗和硒消解损失、硒和碲信号弱以及硒的质谱干扰难题,克服了传统单四极杆ICP-MS测定硒依赖王水水浴半溶的局限,实现了典型地质样品(土壤、水系沉积物)中5种关键矿产元素的一次溶样、高效、高灵敏同时测定。

     

    Abstract: Gallium, indium, germanium, selenium and tellurium are extremely scarce and widely dispersed in the Earth’s crust, which have been included in the critical mineral list due to their extensive application in modern clean energy transitions. Traditional analytical methods are limited by their weak mass spectrometric response and severe interference (especially selenium), requiring the use of two techniques, inductively coupled plasma-mass spectrometry (ICP-MS) and hydride generation atomic fluorescence spectrometry (HG-AFS), which cannot achieve simultaneous determination of the same sample after one dissolution. An open-vessel digestion with HF-HNO3-HClO4 was employed to prevent volatilization of Ge and Se while ensuring complete decomposition. Isopropanol (2%, V/V) was selected as a sensitizer to improve the MS response of 80Se and 128Te by 2.75- and 2.32-fold, respectively. The severe mass spectrometric interference on 80Se was eliminated by the mass-shift mode with oxygen as the reaction gas in inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS), and the signal-to-noise ratio for Se reached 58.20. A simultaneous determination method for Ga, In, Ge, Se and Te by ICP-MS/MS was established in this study. The detection limits of this method ranged from 0.002 to 0.060g/g, and the ΔlgC values for six certified reference materials were all within ±0.05, with an RSD of <5%. The method established in this study addresses the drawbacks of Ge and Se being prone to volatilization loss during digestion, the poor MS response of Se and Te, and the severe interference on Se in single-quadrupole ICP-MS, which typically necessitates aqua regia semi-digestion. This method achieves the simultaneous determination of the five critical mineral elements Ga, In, Ge, Te, and Se in typical geological samples (soil and stream sediments) in a single run.

     

/

返回文章
返回