Determination of Sc,Y and Rare Earth Elements in Geochemical Samples by High Resolution Inductively Coupled Plasma-Mass Spectrometry

An analytical method for the determination of Sc,Y and 14 rare earth elements(La,Ce,P,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu) by high resolution inductively coupled plasma-mass spectrometry(HR-ICP-MS) has been developed.Samples were decomposed by HF-HNO3-H2SO4-aqua regia,then 16 elements above in the solution were directly analyzed by HR-ICP-MS.The spectra interferences from polyatomic ions and oxide ions(MO+) could be avoided by measuring at high resolution mode.The optimal determination isotopes and appropriate resolution for rare earth elements(REEs) were selected.The operating parameters of HR-ICP-MS were optimized by testing geochemical standard materials with plenty of matrix.The detection limits(6σ) of the method for REEs were 0.003～0.013 μg/g(DF=1000).The relative standard deviation(RSD) was less than 6%(n=12).The method has been applied to determination of Sc,Y and REEs in geochemical national standard reference materials and the analytical results were in agreement with the certified values.