Study of Am and Pu behavior in alkaline media

The redox chemical behavior of americium and plutonium species in alkaline media has been studied, mainly two dis/reproportionation reactions: 2Pu(VI)=Pu(V)+Pu(VII) and Am(III)+Am(V)=2Am(IV). It was found that Am(VI) is readily reduced by the simple action of water, and that radiolysis has no effect. This is a marked departure from the behavior of Am in other media, where alpha particle self-irradiation generates redox active species that affect the Am oxidation state. An Am(VII) compound has been synthesized. All results are interesting for the treatment of alkaline high-level radioactive wastes.