Sequential separation of actinides by ion chromatography coupled with on-line scintillation detection

摘要

The separation and measurement of actinides by ion chromatography (IC) coupled with on-line scintillation detection was investigated. Separation of ~(237)Np, ~(239)Pu, ~(241)Am, ~(244)Cm, ~(230)Th, and ~(233)U was accomplished using a Dionex CG5 guard column, CS5 separation column, and an elution program utilizing oxalic, diglycolic, and nitric acid eluents. Np(V) was eluted as a weak anionic oxalate complex or as free NpO_2~+ cation, Am(III) and Cm(III) as anionic oxalate complexes, Pu(IV) and Th(IV) as nonionic diglycolate complexes, and U(VI) as a free uranyl cation. Response of the flow-cell detector was linear over the full range of activities tested (4-1500 Bq). The minimum detectable activities for the investigated analytes ranged from 3.6 Bq for ~(244)Cm to 5.4 Bq for ~(230)Th and ~(239)Pu. The corresponding minimum detectable concentrations based on a 1-L sample ranged from 3.6 to 5.4 KBq m~(-3) (96 to 150 pCi L~(-1)).