Separation of americium(III) and lanthanide(III) ions using TPEN analogs

Fugate, G.*; Takeshita, Kenji*; Matsumura, Tatsuro  

The compound N,N,N',N'-tetrakis(methylpyridyl)-1,2-ethylenediamine (TPEN) has been shown previously to exhibit a high separation factor for the separation of americium(III) and europium(III) but the application of this material to the nuclear fuel cycle is limited because of pH range of the separation (pH3 to 6) and the high solubility of the compound in acidic aqueous media. A variety of compounds have been synthesized during the course of this study in an attempt to retain the separation factor found in the parent compound while decreasing the working pH and aqueous solubility of the extractant. A series of compounds was synthesized in which the ethylene linker was replaced by several aromatic compounds. Another series of analogs was synthesized replacing two or more of the methylpyridyl groups with several different functional moieties. The separation properties of these new compounds were characterized and will be presented.