Determination of trace amounts of rare earth elements in highly pure praseodymium oxide by double focusing inductively coupled plasma mass spectrometry and high-performance liquid chromatography

Abstract

An analytical method for the determination of traces of rare earth elements (REE) as impurities in highly pure praseodymium oxide (Pr 6O 11) produced at the Instituto de Pesquisas Energéticas e Nucleares (IPEN) and a comparison with commercial praseodymium oxide as a certified reference is reported. REE as impurities in praseodymium oxide were separated from the matrix by high-performance liquid chromatography (HPLC). The separated individual fractions containing REE trace impurities were analyzed directly by inductively coupled plasma sector field mass spectrometry (HR ICP-MS). The percentage recovery ranged from 85 to 100% for different rare earth elements. The mean RSD of the method varied between 3 and 5% for a set of five replicates for the IPEN material and for the certified reference sample. Both materials were found to be highly pure (>99.9%).