ICP-AES Determination of 14 Rare Earth Elements as Impurities in High-Purity Lutecium Oxide

Fourteen rare earth elements as impurities in high-purity lutecium oxide were determined by ICP-AES. 0.500 0 g of Lu2O3 sample was taken and dissolved in HCl(1+1) 20 mL with addition of 0.5 mL of H2O2. The solution was diluted to 100 mL in a volumetric flask and used for ICP-AES analysis. For choice of analytical spectral lines for each of the 14 RE elements, several spectral lines having higher intensities and lower excitation potentials were chosen preliminarily by referring to the spectra table, and then by sketch scanning of these spectral lines, the spectral lines with flat background, larger S/N values and less interferences from matrix and co-existing elements were finally chosen as the analytical spectral lines. Standards were prepared by additon of 5 g·L-1 Lu2O3 solution for matrix matching, and alternate additon of the RE oxide standards. The proposed method was feasible for analysis of Lu2O3 with their purities in the range of 99%-99.99%. Precision of the method was tested and values of RSD′s (n=11) were found in the range of 0.56%-4.2%. Values of recovery found by standard addition method were in the range of 95%-106%.