PNNL

Abstract

The 235U-231Pa chronometer remains underutilized due to the lack of a practical yield tracer for 231Pa. Isotopic dilution-mass spectrometry based quantification of 231Pa requires the preparation of a standardized 233Pa spike. This study evaluates silica gel and 1-octanol column media for the isolation of 233Pa from its 237Np parent and 233U daughter (Th is also evaluated). Precision column deliveries for this method comparison were performed using an automated fluidic system. The findings demonstrate that silica gel columns achieve good Pa purities, but lack efficient elution performance. Significant improvements are noted using TK400 resin, where Pa purities are higher, and elution is rapid.