Determination of ultra-trace plutonium by online high-speed countercurrent chromatography coupled with inductively coupled plasma mass spectrometry

The approach of the determination of ultra-trace plutonium via online high speed countercurrent chromatography (HSCCC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) was developed by connecting the outlet of CCC to the sampler of ICP-MS. The retention ratio of stationary phase of some two-phase systems were studied, 1% Tri-n-octyl amine (NOA) in heptane was utilized as the stationary phase, the matrix and interference elements, such as uranium and thorium, can be eliminated while plutonium concentrated. Both the quantification of plutonium and the proper separation condition were studied. The concentration of plutonium-239 in the soil determined by this method coincided with the result obtained from the traditional anion-exchange-separation-ICP-MS-determination method.