DETERMINATION OF TRACE AMOUNTS OF PB, MN AND CO IN ACIDIC SOLUTIONS OF ZIRCONIUM AND MOLYBDENUM BY GF-AAS

Graphite furnace atomic absorption spectrometry (GF-AAS) has been appl ied to the direct determination of trace amounts of Pb, Mn, and Co in the respective acidic solutions of high-purity zirconium and molybdenu m. Platform atomization in a pyrolytically coated graphite tube permit ted high sensitive and precise determination of Pb, Mn and Co in zirco nium and that of Mn and Pb in molybdenum. However, graphite tube wall atomization using a sample solution modified with nickel nitrate was r equired for the determination of Co in molybdenum. When the weighed am ount of the sample was 1 g, the limits of detection (3 sigma of blank values) were 0.12 ppm of Pb, 0.04 ppm of Mn and 0.07 ppm of Co for the zirconium sample, and 0.03 ppm of Pb, 0.05 ppm of Mn and 0.10 ppm of Co for the molybdenum sample. Moreover, the analytical values obtained for Pb, Mn and Co in the JAERI CRM Z11-Z13 zircaloys showed good agre ement with their certified values. The proposed analytical procedure c ould be applied to rapid analyses of other refractory metal samples by using the sample solutions without pretreatments such as separation o f the carbide-forming matrix elements.