Release of 226Ra from uranium mill tailings by microbial Fe(III) reduction

E. R. Landa; Elizabeth J.P. Phillips; Derek R. Lovley

doi:10.1016/0883-2927(91)90075-z

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Release of 226Ra from uranium mill tailings by microbial Fe(III) reduction

E. R. Landa·Elizabeth J.P. Phillips·Derek R. Lovley

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Abstract

Uranium mill tailings were anaerobically incubated in the presence of H 2 with Alteromonas putrefaciens , a bacterium known to couple the oxidation of H 2 and organic compounds to the reduction of Fe(III) oxides. There was a direct correlation between the extent of Fe(III) reduction and the accumulation of dissolved 226 Ra. In sterile tailings in which Fe(III) was not reduced, there was negligible leaching of 226 Ra. The behavior of Ba was similar to that of Ra in inoculated and sterile systems. These results demonstrate that under anaerobic conditions, microbial reduction of Fe(III) may result in the release of dissolved 226 Ra from uranium mill tailings.

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E. R. Landa, Elizabeth J.P. Phillips, Derek R. Lovley. 1991. Release of 226Ra from uranium mill tailings by microbial Fe(III) reduction. https://doi.org/10.1016/0883-2927(91)90075-z

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