High-Resolution Inductively Coupled Plasma Atomic Emission Spectrometry for the Determination of Burnup in Spent Nuclear Fuel

Abstract

The development of a method for the estimation of burnup of nuclear fuels by the determination of ²³⁶U by high-resolution inductively coupled plasma spectrometry has been demonstrated. Linear calibration curves are obtained and a limit of quantification of ∼ 3 atom % burnup established. The precision, in terms of the relative standard deviation (RSD) of the determination, was 3.7% RSD for 1.58 atom % of ²³⁶U. These results were obtained by using a spectrometer with a resolving power of 2.3 × 10⁵ and with the application of a spectral deconvolution using a nonlinear curve-fitting algorithm. A complementary method, the determination of ¹³⁹La, was also investigated and proved to be accurate (recovery = 101.5%) and precise (RSD = 2.2%) with a limit of quantification of ∼ 0.5 atom % burnup. These methods were developed with the use of model solutions which approximate digests of irradiated fuels but which contained no active fission product species.