Association of radionuclides with colloids in soil solutions

• Published in: Radiochemistry (New York, N.Y.) Vol. 51; no. 2; pp. 201 - 210
• Main Authors: Goryachenkova, T. A., Kazinskaya, I. E., Kuzovkina, E. V., Novikov, A. P., Myasoedov, B. F.
• Format: Journal Article
• Language: English
• Published: Dordrecht SP MAIK Nauka/Interperiodica 01-04-2009
• Subjects: Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Nuclear Chemistry; 82.70.Dd
• ISSN: 1066-3622; 1608-3288
• DOI: 10.1134/S1066362209020209

Association of Pu and Am with variously sized particles in soil extracts is studied by ultrafiltration. In aqueous extracts, the Pu and Am concentrations depend on the soil type and aqueous solution composition. In the aqueous extracts, from 60 to 100% of the radionuclides and organic carbon are associated with fine colloidal particles (<0.05 μm). The presence of humic acid increases the recovery of radionuclides by a factor of 4–8 depending on the soil type. The Pu and Am distribution among the groups and fractions of humus acids is studied. In the group of humic acids of chernozem, from 65 to 75% of the radionuclides are associated with the fraction with MW > 100 kDa; about 25%, with the fraction with MW 50–10 kDa; and 2–4%, with the low-molecular-weight fraction with MW < 3 kDa. In the group of fulvic acids, 44–49% of the radionuclides is found in the fraction with MW > 100 kDa, and 42–51%, in the fraction with MW < 3 kDa.