Microbially Mediated Removal of Np (V) by Desulfovibrio desulfuricans
Implication of Microbial Immobilization at the Radioactive Waste Repository
2005 年 6 巻 1 号 p. 85-86
詳細
2005 年 6 巻 1 号 p. 85-86
We investigated the capacity of the sulfate-reducing bacterium Desulfovibrio desulfuricans to facilitate the removal of Np (V) from aqueous solution. For comparison, we also examined the removal of Np (V) by bentonite under aerobic and anaerobic conditions with sodium sulfide. Np (V) removal (probably afteer reduction to Np (IV) ) was most rapid in the presence of cells, whereas there was little or no removal by bentonite under aerobic conditions. In the presence of cells, Np in suspension declined by 95% or more within 10h, suggesting that D. desulfuricans enzymatically reduces mobile Np (V) to immobile Np (IV) and eventually to stable Np, though chemical reduction by cell metabolite H2S may contribute. This finding highlights the importance of understanding microbial effects when considering the migration of radioactive elements from waste repositories.
