Oxidation states and speciation of plutonium in systems of high ionic strength

Oxidation states and speciation of plutonium have been investigated in high saline systems in order to obtain reliable data for modeling safety scenarios for radioactive waste repositories. The methods applied are specific voltametry which can cope with the conditions in these media, optical and extraction procedures, combined with iteration processes, newly developed for calculating even small complex formation constants. The advantages of the electrochemical methods are the high sensitivity, the absence of any influence on equilibria and the applicability on a variety of complex formation constants to be determined especially with respect to those of the actinides, which still are urgently needed for these media to close the data gap