Photo-oxidation of two malonamides, extractant models for minor actinides in nuclear fuel reprocessing

The photo-oxidation of two potential extractants, the N,N′-dimethyl, N,N′-dibutyl, tetradecyl malonamide (DMDBTDMA) and the N,N′-dimethyl, N,N′-dibutyl, dodecylethoxy malonamide (DMDBDDEMA) for minor actinides in nuclear fuel reprocessing was followed. The main photoproducts, identified by coupled techniques (GC/FTIR and GC/MS) are malonamides, monoamides and carbonylate derivatives. An irradiation, for 1 h, with a low mercury pressure lamp can destroy initial diamides diluted at 0.075 mol l−1 in n-dodecane. With pure solutions of diamides (2.05 mol l−1), destruction needs several hours to be complete. Both diamides only differ by an ether bond, their reactivity under different conditions of photo-oxidation is discussed.