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. |