Neptunium speciation in soils

• Published in: Radiochemistry (New York, N.Y.) Vol. 56; no. 2; pp. 216 - 221
• Main Authors: Lavrinovich, E. A., Goryachenkova, T. A., Abramova, A. V., Novikov, A. P.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01-03-2014
• Subjects: Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Nuclear Chemistry; fulvic acids; humic acids; neptunium; americium; soils; plutonium; speciation
• ISSN: 1066-3622; 1608-3288
• DOI: 10.1134/S1066362214020155

The relative content of
237
Np in the water-soluble form depends on the soil type and decreases in the following order: sandy loam soil > soddy podzolic soil > chernozem (black soil). The fraction of the most mobile forms of
237
Np decreases with an increase in the content of organic carbon in soils. The major fraction of
237
Np is associated with the fulvic acid (FA) group (90.3 and 71.0% of the total neptunium content for soddy podzolic soil and chernozem, respectively), with 8.6 and 18.7% of
237
Np, respectively, associated with the humic acid (HA) group. In the FA group, the major fraction of
237
Np is associated with low-molecular-weight organic compounds and with FA, free or bonded mainly with relatively mobile hydroxides of Fe, Al, Mn, etc. (R
2
O
3
·
n
H
2
O) (fractions 1a and 1).