オンラインカラム／同位体希釈ICP-MS法による環境試料中Puの分析

Abstract

This paper describes the development of on-line column/ID-ICP-MS technique using UTEVA-Spec. resin for plutonium (Pu) analysis of environmental samples. The UTEVA-Spec. resin, which comprises of DAAP (Diomyl-amylphosphonate) adsorbed on an inert polymeric support, has been used for separating actinide elements. In the present method, Pu in 3M nitric acid solution was fed to the UTEVA-Spec. resin, then, eluted from the resin by reducing Pu to Pu(III) with 3M nitric acid mixed with ascorbic acid. Uranium was not reduced by the eluting solution, and retained on the resin. Outflow from the resin column was directly introduced to an ICP-MS system. It took 40 minutes to determine Pu in sample solution including resin column conditioning. Chemical recovery of Pu in column operation was 70 percent, and the typical lower detection limits for Pu-239, Pu-240 and Pu-242 were 9.2, 4.3 and 7.5 fg (21, 36 and 1.1 micro-Bq), respectively. Five international standard materials for Pu were analyzed, and good results were obtained.