Development of ion exchange chelators for actinide separations

Our group has recently developed a new family of chelating ligands that contain both phosphoryl and N-oxide donor centers. In particular, [Ph{sub 2}P(O)CH{sub 2}]{sub 2}C{sub 5}H{sub 3}NO, is a ligand that strongly binds trivalent actinide and lanthanide ions present in strongly acidic solutions. It has been shown that this ligand binds in a neutral form. not through an ionic displacement process. Phosphonic acid derivatives of this ligand, on the other hand, do bind by H{sup +} displacement and this coordination behavior will be discussed together with the results of binding with other phosphonic acid ligands.