冷凝回流三酸体系消解—ICP-MS法测定高纯石墨中的痕量杂质元素

Determination of Impurity Elements in High Purity Graphite by ICP-MS after Mixture Acid Digestion in Reflux Condenser System

摘要: 建立冷凝回流混合酸消解，ICP-MS法测定高纯石墨中35种痕量元素的方法。采用1 mL HNO₃，1 mLHClO₄和3 mL H₂SO₄于220 ℃消解0.2 g 样品，以Sc、Rh、Cs、Re作内标，ICP-MS法测定各元素的方法检出限为0.000 6~0.1 μg•L^-1，加标回收率达82%~110%，相对标准偏差（RSD，n=10）为0.58%～5.8%。该方法适用于高纯石墨中痕量杂质含量的测定。

Abstract: The method of determination of 35 trace impurity elements in high purity graphite was established. Samples were digested by the mixture of 1 mL HNO₃，1 mL HClO₄ and 3 mL H₂SO₄at 220 ℃ in reflux condenser system. Sc, Rh, Re and Cs were utilized as internal standards to correct the signal drift. The detection limit of various elements is from 0.000 6 μg•L^-1to 0.1 μg•L^-1, the recovery rates are between 82% and 110%, the RSD(n=10) is in the range of 0.58% and 5.8%. The method is suitable for the determination of impurity elements in high purity graphite.