Determination of Cerium Concentration in High-Purity Oxide Lanthanum by ICP-MS

Ce concentration in high-purity La₂O₃ was determined by inductively coupled plasma mass spectrometry (ICP-MS). Isotopes ¹⁴⁰Ce and ¹⁴²Ce were chosen to be determined. Correction equations were built to investigate the effect of Nd concentration in La₂O₃ on ¹⁴⁰Ce and ¹⁴²Ce mass interferences and correction results. The results indicate that the correction effect of ¹⁴²Ce mass interferences is bad when Nd concentration is high. The recovery is —322% and the RSD is 173%. While the correction effect of ¹⁴⁰Ce mass interferences is very well. The method of Ce concentration determination in La₂O₃ is built, when Ce concentration is high. The detection limit of ¹⁴⁰Ce is 1.5 μg/g, the RSD is between 0.72% and 1.6% and the recovery is in the range of 104%—106%.