Validation of an inductively coupled plasma mass spectrometry (ICP-MS) method for the determination of cerium, strontium, and titanium in ceramic materials used in radiological dispersal devices (RDDs)

Abstract

In radiological dispersal device (RDD) studies, sintered ceramics made of CeO 2 and SrTiO 3 were used to simulate actinide oxides and 90SrTiO 3, respectively. Instrumental neutron activation analysis (INAA), inductively coupled plasma optical emission spectroscopy (ICP-OES), and inductively coupled plasma mass spectrometry (ICP-MS) were investigated as possible analytical techniques for the measurement of SrTiO 3 and CeO 2 constituents in powder forms, sintered ceramics, and air particulates collected following a detonation. For ICP-OES and ICP-MS analysis, new digestion procedures were developed using a closed-vessel microwave apparatus. Acid mixtures (HNO 3:H 2O 2:HF (16:2:1) and HNO 3:H 2O 2 (1:4)) were found to be effective for the digestion of SrTiO 3 and CeO 2, respectively. The intercomparison study confirmed that the results obtained by ICP-OES/MS are in good agreement with INAA results. This also confirms the efficiency of the digestion procedures for these refractory materials and the inter-exchangeability of the instrumentation tested. Comparison between the ICP-OES and the ICP-MS instrumentation for the determination of air particulates shows, that although the two methods are equivalent, ICP-MS provides better detection limits (0.11, 0.02, and 0.04 μg per filter for Ti, Sr, and Ce, respectively) and the possibility to determine isotopic fractionation as the result of an explosion.