Comparative Evaluation of DHDECMP (Dihexyl-N,N-Diethylcarbamoyl-Methylphosphonate) and CMPO (Octylphenyl-N,N,-Diisobutylcarbamoylmethylphosphine Oxide) as Extractants for Recovering Actinides from Nitric Acid Waste Streams

摘要

Certain neutral, bifunctional organophosphorous compounds are of special value to the nuclear industry. Dihexyl-N,N-diethylcarbomoylmethylphosphonate (DHDECMP) and octylphenyl-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) are highly selective extractants for removing actinide and lanthanide elements from nitric acid. We obtained these two extractants from newly available commercial sources and evaluated them for recovering Am(III), Pu(IV), and U(VI) from nitric acid waste streams of plutonium processing operations. Variables included the extractant (DHSECMP or CMPO), extractant/tributylphosphate ratio, diluent, nitrate concentration, nitrate salt/nitric acid ratio, fluoride concentration, and contact time. Based on these experimental data, we selected DHDECMP as the perferred extractant for this application. 18 refs., 30 figs. (ERA citation 13:029281)