Determination of ultra-trace amounts of uranium and thorium in high-purity aluminium by inductively coupled plasma mass spectrometry

Abstract

A sensitive method is decribed for the simultaneous determination of ultra-trace amounts of uranium and thorium in high-purity aluminium by inductively coupled plasma mass spectrometry (ICP-MS). Uranium and thorium were separated from a sample solution of 10 mol dm^–3 hydrochloric acid by extraction with a 10% v/v solution of tributyl phosphate in cyclohexane. The internal standard method was used for quantification by ICP-MS. For a sample mass of 10 g, the detection limits for uranium and thorium are 7 and 8 pg g^–1, respectively.