ICP-MS法测定高纯钯中18个痕量杂质元素

摘要

After the sample was digested with mixed acid (hydrochloric acid - nitric acid), eighteen impurity elements in palladium were determined by inductively coupled plasma mass spectrometry (ICP-MS). Under the optimized experiment conditions, the analysis of Pt, Rh, Ir, Ru, Au, Ag, Cu, Fe, Zn, Ni, Mn, Mg, Al, Sn and Pb, was performed by normal mode whereas the analysis of Si, Fe and Cr were carried out by reaction gas NH3 mode using reaction cell technology at the flow rate of NH3 gas set at 0.2, 0.3 and 0.7 mL/min, respectively. Internal standard method was used to improve the accuracy. Sc was selected as an internal standard for correcting Mg, Al, Zn, Ni, Mn, Cu, Ag, Rh, Ru and Si, Y for Fe, In for Sn, Cr and Pb, and Re for Ir, Au, Bi and Pt. The linear correlation coefficient (r) was larger than 0.9997. The detection limits were 0.006~0.85 ng/mL,and the recoveries of standard addition were 86.2%~118.8%. The relative standard deviation (RSD) was found to be 1.38%~6.11% for 18 elements in the high-purity palladium sample. The method can be used for the analysis of high-purity palladium products of 4N~5N.%以混合酸(恿酸-硝酸)溶解高纯钯样品,建立了电感耦合等离子体质谱法(ICP-MS)测定高纯钯中18个杂质元素的方法.确定了最佳测定条件为:采用普通模式测定Pt、Rh、Ir、Ru、Au、Ag、Cu、Fe、Zn、Ni、Mn、Mg、Al、Sn和Pb,氨气反应模式测定Si、Fe和Cr(氨气流速分别为0.2、0.3和0.7 mL/min);采用内标校正提高分析的准确性,其中Mg、Al、Zn、Ni、Mn、Cu、Ag、Rh、Ru和Si以Sc为内标,Fe以Y为内标,Sn、Cr和Pb以In为内标,Ir、Au、Bi、Pt以Re为内标.测定各元素的线性相关系数(r)不小于0.9997,方法检出限为0.0061~0.85 ng/mL.对高纯钯样品中18个杂质元素进行测定,相对标准偏差(RSD)为1.38%~6.11%,加标回收率86.2%~118.8%,可满足4N~5N高纯钯产品的测定要求.