Separation and coprecipitation of lanthanides and americium by photolysis

Journal Article · Tue Apr 01 04:00:00 EST 1997 · Nuclear Technology

OSTI ID:477291

Tsushima, Satoru; Nagasaki, Shinya; Suzuki, Atsuyuki ^[1]

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1. Univ. of Tokyo (Japan). Dept. of Quantum Engineering and Systems Science

Photochemical techniques are used for the mutual separation of lanthanide elements. By emitting light from an ultrahigh-pressure mercury lamp to a nitric acid solution that contains fourfold mixtures of lanthanide elements (neodymium, samarium, europium, and gadolinium), (NH{sub 4}){sub 2}SO{sub 4}, and isopropyl formate, neodymium, samarium, and europium are photoreduced and form Ln{sup 2+} sulfates, while gadolinium is not photo-reduced and does not coprecipitate. When lanthanum is introduced instead of gadolinium, lanthanum coprecipitates along with neodymium, samarium, and europium. These results are explained by photolyzing Nd-Gd and Nd-La systems for comparison, and the difference in precipitation behaviors between these two systems is explained by the differences in ion size of these elements. Photolysis is also performed for a Nd-Am system. Am{sup 3+} is carried along with neodymium and coprecipitated. As a way to decrease the amount of americium carried along with neodymium, americium is photochemically oxidized by emitting light from a deuterium lamp as well as from a mercury lamp. The fraction of americium carried with neodymium decreases with the use of this technique. This result is also explained by the differences in ion size of these elements.

• OSTI ID: 477291
• Journal Information: Nuclear Technology, Journal Name: Nuclear Technology Journal Issue: 1 Vol. 118; ISSN 0029-5450; ISSN NUTYBB
• Country of Publication: United States
• Language: English

Related Subjects

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