Electrochemical Separation of Curium and Americium

The objective of this project is to develop a method for the separation of Am from Cm based on electrochemical techniques. Electrochemical systems that allow the thermodynamics of actinide and lanthanide complexes to be systematically evaluated and tuned will be examined. The influence of complex formation on the ability to selectively isolate a given species electrochemically will be evaluated. Metal-ligand complex formation provides a useful derivation technique to increase solubility in solution environments that favor precipitation. In addition, the thermodynamic properties of a complex relative to the isolated species may be shifted to more suitably measurable electrochemical separation regimes. Electrochemical sorption methods are well suited for use in the separation of similar chemical species where the applied potential provides the thermodynamic selectivity required. Traditional separation techniques will be evaluated using common electrodes such as Hg, Au/Hg film, and glassy carbon. In addition, conductive polymer such as polypyrrole will examined to provide a more novel method of separating and sequestering of actinide and lanthanide chemical species. The polymer composite electrodes will be chemically modified with chelating and the separation of chemical species based on the adsorption/desorption thermodynamics of the polymer relative to the complex or isolate species will be probed. The proposed experiments will provide a comprehensive survey of the effect of complex formation and species on the ability to separate complex mixtures of actinide and lanthanide complexes in aqueous environments using electrochemical methods and modified polymer electrodes. Work Proposed for Year 2004 2005, Goals, and Expected Results: Year one of the project will develop the lab facilities required for the electrochemical experiments. The electrochemical workstation will be acquired and necessary electrodes, reagents, and supplies will be purchased. The year one goals are to prepare and electrochemically evaluate the complexes and species of interest in this study or species that closely resemble more hazardous counterparts. These studies will be important for the future studies of polypyrrole membranes providing the required thermodynamic data concerning the complexes formed and possible separation of complex mixtures. Funding Requested: Funding Year 2004-2005 2005-2006 2006-2007 Total ($K) $131,105 $117,788 $120,812