Evaluation of silver-impregnated activated carbons for I-129 and Tc-99 from an acidic groundwater

NUCL 70

Steven M. Serkiz1, K.M. Kanzleiter1, Erin E. Cumbie2, and Tanju Karanfil3. (1) Savannah River Technology Center, Westinghouse Savannah River Company, 773A rm B121, Aiken, SC 29808, (2) Environmental Engineering and Science Dept, Clemson University, Clemson, SC, (3) Department of Environmental Engineering and Science, Clemson University, 342 Computer Court, Clemson, SC 29634-0919
Iodine-129 and Technetium-99 are long-lived nuclides and because they are predominately anionic species their removal from aqueous waste streams is often difficult. Data will be presented on the removal of I-129 and Tc-99 from contaminated groundwater at the Department of Energy’s Savannah River Site (SRS) using commercially available anion exchange resin, activated carbon, and several silver impregnated activated carbons (SIACs) in column breakthrough experiments. A range of SIAC materials, including Ag(0) and AgCl impregnated materials, were tested to examine the effects of silver content and silver surface speciation on anion removal. Because the low disposal limits for I-129 bearing waste, the spent sorbent leaching properties were evaluated using standard leaching protocols. The results from this study show that the SIACs and the commercially available anion exchange resin were effective in removing I-129 and Tc-99 from the feed water to low levels. The secondary waste leaching properties of the SIACs, however, appear superior to the organic-based anion resin tested in this work.