SREL Reprint #2328

Comparison of acid and base leach for the removal of uranium from contaminated soil and catch-box media

Martine C. Duff1,2, Caroline F. V. Mason1, and Douglas B. Hunter2

1Los Alamos National Laboratory, Chemical Sciences and Technology Division, P.O. Box 1663, MS J534,
Los Alamos, NM, 87545, USA (LA-UR-97-2111)
2Advanced Analytical Center for Environmental Sciences, The University of Georgia's
Savannah River Ecology Laboratory, Drawer E, Aiken, SC, 29801

Abstract: Several leach solutions have been developed for the removal of uranium (U) from contaminated media such as soil and military catch-box sand used for the ballistics testing of U-containing projectiles. Leach solutions of concentrated sulfuric acid and of carbonate (with and without oxidants such as peroxides) have also been used in the mining of U from high-grade ore deposits. Many of these solutions have been used at U-contaminated environmental sites with varying degrees of success. Batch leaches with six characterized U-contaminated media and seven leach solutions were conducted. After the leach solutions were reacted with the media (five soils and a catch-box sand), the solutions were analyzed for dissolved U, Ca, Si, Fe, Mn, Ph and Cr. We study the ability of acidic, basic, acidic-oxidizing and basic-oxidizing solutions to leach U from contaminated media. The results suggest the removal efficiency of soil U for each leach solution varies with the nature of the U-contamination in the media and the media composition. It is likely the forms of U in the contaminated media such as reduced, absorbed, complexed and solid species influence the solubilization of U by the leaching agents.

Keywords: Uranium, synchrotron X-ray fluorescence (SXRF), remediation, chromium, lead, leaching, catch-boxes

SREL Reprint #2328

Duff, M.C., C.F.V. Mason, and D.B. Hunter. 1998. Comparison of acid and base leach for the removal of uranium from contaminated soil and catch-box media. Canadian Journal of Soil Science 675-683.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).