Oxidative Dissolution of Biogenic Uraninite in Groundwater at Old Rifle, CO

被引：61

作者：

Campbell, Kate M. ^{[1
]}

Veeramani, Harish ^{[2
]}

Urich, Kai-Uwe ^{[3
]}

Blue, Lisa Y. ^{[3
]}

Giammar, Daniel E. ^{[3
]}

Bernier-Latmani, Rizlan ^{[2
]}

Stubbs, Joanne E. ^{[4
]}

Suvorova, Elena ^{[2
]}

Yabusaki, Steve ^{[5
]}

Lezama-Pacheco, Juan S. ^{[4
]}

Mehta, Apurva ^{[4
]}

Long, Philip E. ^{[5
]}

Bargar, John R. ^{[4
]}

机构：

[1] US Geol Survey, Boulder, CO 80303 USA

[2] Ecole Polytech Fed Lausanne, Environm Microbiol Lab, CH-1015 Lausanne, Switzerland

[3] Washington Univ, St Louis, MO 63130 USA

[4] Stanford Synchrotron Radiat Lightsource, Menlo Pk, CA 94025 USA

[5] Pacific NW Natl Lab, Richland, WA 99352 USA

来源：

ENVIRONMENTAL SCIENCE & TECHNOLOGY | 2011年 / 45卷 / 20期

关键词：

URANIUM; REDUCTION; U(VI); BIOREDUCTION; REOXIDATION; BIOREMEDIATION; NANOPARTICLES; CONTAMINATION; TRANSPORT; UO2;

D O I：

10.1021/es200482f

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

Reductive bioremediation is currently being explored as a possible strategy for uranium-contaminated aquifers such as the Old Rifle site (Colorado). The stability of U(IV) phases under oxidizing conditions is key to the performance of this procedure. An in situ method was developed to study oxidative dissolution of biogenic uraninite (UO2), a desirable U(VI) bioreduction product, in the Old Rifle, CO, aquifer under different variable oxygen conditions. Overall uranium loss rates were 50-100 times slower than laboratory rates. After accounting for molecular diffusion through the sample holders, a reactive transport model using laboratory dissolution rates was able to predict overall uranium loss. The presence of biomass further retarded diffusion and oxidation rates. These results confirm the importance of diffusion in controlling in-aquifer U(IV) oxidation rates. Upon retrieval, uraninite was found to be free of U(VI), indicating dissolution occurred via oxidation and removal of surface atoms. Interaction of groundwater solutes such as Ca2+ or silicate with uraninite surfaces also may retard in-aquifer U loss rates. These results indicate that the prolonged stability of U(IV) species in aquifers is strongly influenced by permeability, the presence of bacterial cells and cell exudates, and groundwater geochemistry.

引用

页码：8748 / 8754

页数：7

共 37 条

[1] Stimulating the in situ activity of Geobacter species to remove uranium from the groundwater of a uranium-contaminated aquifer [J].