Separation of Americium (III) and Lanthanide (III) Ions using TPEN Analogs

Abstract

N,N,N′,N′-tetrakis(2-pyridylmethyl)-1,2-ethylenediamine (TPEN) has been shown previously to exhibit a high separation factor for the separation of americium (III) and europium (III). Application of TPEN is limited due to the solubility of the material under acidic conditions (pH < 4). A variety of analogs were synthesized in this study to examine effects caused by various structural modifications in an effort to retain the selectivity of the parent compound while decreasing solubility in acidic media. Results indicate that the substitution at the ethylene linker of TPEN eliminates the ability of the compound to separate americium (III) over europium (III).

Keywords:

• Americium
• Europium
• Soft donor
• TPEN

ACKOWLEDGEMENTS

This research was funded by the Ministry of Education, Culture, Sports, Science and Technology of Japan. The authors would like to thank Prof. Nash, Washington State University, and Prof. Mori, Kobe University, for the valuable discussions on the synthesis and complexation of TPEN.

Notes

∗Extraction conditions: 0.1 M ammonium nitrate, nitrobenzene, 1.0 mM TPEN, 30 minutes contact time.

∗Work was performed on sabbatical from Savannah River National Laboratory, Aiken, SC, USA.