The Radiation Chemistry of CMPO: Part 2. Alpha Radiolysis

Octylphenyl-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) was irradiated using 60Co γ-rays, and post-irradiation samples were analyzed for the decrease in CMPO concentration, the appearance of degradation products, and the effects on americium solvent extraction. The –G-value for the radiolytic degradation of CMPO depends on the presence of nitric acid and oxygen during irradiation, with both providing protection from radiolytic degradation. The –G-value does not depend on the γ-ray dose rate or the CMPO concentration. Effects on solvent extraction performance were independent of the change in CMPO concentration, but rather related to the nature of the degradation products. The main products were identified by ESI-MS and were different for irradiation in the presence of nitric acid.