Abstract: P_(507)Extraction Chromatographic Separation Spark Source Mass Spctrometric Determination of 14 Rare Earths Impurities in High Purity Gadolinium OxideWang Zishu;Sui Xiyun;Niu Na;Liang Yujun (Changchun Institue of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China)Abstract:The separation of rare earth impurities in high purity gadolinium oxide have been carried out with 2-ethylhexyl hydrogen- 2-ethylhexyl phoshonate (P507) extraction chromatography ; hydrochloric acid-ammonium chloride serves as eluant. The method of preconcentration and the determination conditions of spark source mass spectrometry have been selected. The measured purity of gadolinium oxide is up to 99.9999 %.Keywords: P_(507) extraction chromatography, high purity rare earth earth, spark source mass specyronetry