A PRELIMINARY-STUDY TO ASSESS THE EFFECT OF SOME SEAWATER COMPONENTS ON THE SPECIATION OF PLUTONIUM

Since Pu(IV) and Pu(V) exhibit very different sediment sorption behavi our, the transport of Pu in the aquatic environment is dependant upon oxidation state and the rate of interconversion between the species. A number of laboratory experiments have been carried out to determine p ossible parameters which influence the rate of Pu redox reactions and the extent of sorption by suspended particulate in the marine environm ent. Results suggest that, although the initial sorption of Pu(IV) did not appear to be dependant upon the major cations present in seawater , the sorption of Pu(V) was decreased in the presence of Ca2+ and Mg2 ions. Both the rates of oxidation of dissolved Pu(IV) and reduction o f dissolved Pu(V) increased with increasing suspended particulate conc entration.