Determination of fifteen rare earth elements in soil, stream sediment and rock samples by X-ray fluorescence spectrometry with pressed powder pellet
The sample was prepared by powder pressing,and 15 rare earth elements (La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Y) in soil,stream sediment and rock samples were determined by wavelength dispersive X-ray fluorescence spectrometer.The measuring conditions of 15 rare earth elements were investigated,including analytical line,analytical crystal,matrix effect and spectral overlapping interference.More than 60 soil,stream sediment and rock CRMs were used to establish calibration curves.The matrix effect was corrected by empirical coefficient method and scattered rays internal standard method.The spectral overlapping interference of rare earth elements was accurately deducted by multiple regression.The detection limits of heavy rare earth elements were mostly below 0.2 μg/g.Precision test was conducted on soil CRMs.The relative standard deviations (RSD,n=10) of determination results of 15 rare earth elements were 0.74 %-17 %.The soil,stream sediment and rock CRMs were analyzed,and the results were consistent with the certified values.