Analytical Application of DHOA for the Determination of Trace Metallic Constituents in Pu-based Fuel Materials by ICP-AES

摘要

DHOA (di-n-hexyl-octanamide) is one of the alternative extractants to TBP (tri-n-butyl phosphate), known for the extraction of plutonium from moderate nitric acid medium without significant extraction of the fission products. The analytical application of DHOA was explored to develop a methodology for the determination of trace metallic constituents in Pu-based nuclear materials. This involved the separation of the Pu matrix by 1.1 M, DHOA-dodecane, followed by the analysis of the raffinate for trace constituents by inductively coupled plasma atomic emission spectrometry (IGP-AES). A systematic study showed that five contacts of 1.1 M DHOA-dodecane were required for the quantitative extraction, of Pu from 3 M HNO_3 feed for a 1g sample size in 10 mL. The feasibility of using DHOA for extraction of Pu from trace: metallic constituents in Pu-based fuel materials without losing trace quantities of analytes of,interest was studied by using synthetic samples after appropriate spiking of the common impurities and critical elements at their required specification limits (common elements: 5 ppm, critical elements: 1 ppm). A systematic study was carried out to compare the analytical performance of DHOA'with TBP which revealed that DHOA could successfully be employed for the determination of,19 trace constituents below the 5 рpm limits for common elements The stripping performance of DHOA was also found to be better in the recovery of Pu from the loaded organic phase.