基于五酸溶样体系-ICP-MS同时测定地质样品中稀土等46种元素

采用HCl-HNO3-HF-HClO4-H2SO45种混合酸溶样体系,敞口一次溶解不同类型的地质样品,逆王水提取,以103 Rh、187 Re为内标元素,三通在线进样方式,建立了电感耦合等离子体质谱(ICP-MS)同时测定地质样品中46种微量、痕量元素及稀土元素的方法。采用五酸溶样体系既避免了三酸或四酸体系对难溶元素的分解不完全,又可消除易挥发元素对测定结果稳定性造成的不良影响。实验结果表明,该方法准确度高、精密度好、检出限低,测定结果与标准物质所提供的参考值基本一致,二者的对数误差绝对值(ΔlgC)均在0.1以内,相对标准偏差(RSD,n=12)均小于5%。该方法操作简单、快速、准确,适用于大批量地质样品中多元素的同时测定。

Simultaneous Determination of 46 Species of Micro,Trace and Rare Earth Elements by ICP-MS Based on the System of Five-Acids Dissolution of Sample

Rare earth elements (REEs) are widely used in electronics, petrochemical, metallurgy, machinery, textile, ceramic, glass, permanent magnetic materialenergy, light industry, environmental protection, agriculture and other fields. With the development of science and technology and breakthrough in applied technology, the application of rare earth elements will continue to expand, and the value of rare earth oxides will become more and more large. Therefore, it is of importance to establish a rapid and accurate determination method for comprehensive utilization of rare earth elements. A method of inductively coupled plasma mass spetrometry (ICP-MS) was developed for simultaneously determining 46 species of micro, trace and rare earth elements in geological samples. The geological samples were dissolved withHCl-HNO₃-HF-HClO₄-H₂SO₄ and extracted by inverse aqua regia. ¹⁰³Rh and ¹⁸⁷Re were used as the internal standard elements, and the National Primary Reference Material (GBW07359, GBW07363, GBW07430 and GBW07457) instead of standard solution of the measured elements was employed to make the standardwork curve. By choosing internal elements, the deviations caused by matrix effect and instrument fluctuation were effectively eliminated. By improving conditions of atomizer velocity, auxiliary gas flow rate and integration time, the optimum experiment conditions were acquired. The influences on test results of refractory and volatile elements of solvent systems were also discussed. Under the optimum test conditions, the method has good accuracy and reproducibility. The correlation coefficient is more than 0.999 0, ΔlgC<0.1, and the relative standard deviation (RSD, n=12) is less than 5.0%. The obtained results are consistent with the reference analytical values. This method is accurate, simple, sensitive and rapid, which can be used for simultaneous determination of multielement in geology samples.