Microanalytical X-ray Imaging of Depleted Uranium Speciation in Environmentally Aged Munitions Residues

详细信息    查看全文

• 作者：Daniel E. Crean ; Francis R. Livens ; Martin C. Stennett ; Daniel Grolimund ; Camelia N. Borca ; Neil C. Hyatt
• 刊名：Environmental Science & Technology
• 出版年：2014
• 出版时间：February 4, 2014
• 年：2014
• 卷：48
• 期：3
• 页码：1467-1474
• 全文大小：539K
• ISSN：1520-5851

文摘

Use of depleted uranium (DU) munitions has resulted in contamination of the near-surface environment with penetrator residues. Uncertainty in the long-term environmental fate of particles produced by impact of DU penetrators with hard targets is a specific concern. In this study DU particles produced in this way and exposed to the surface terrestrial environment for longer than 30 years at a U.K. firing range were characterized using synchrotron X-ray chemical imaging. Two sites were sampled: a surface soil and a disposal area for DU-contaminated wood, and the U speciation was different between the two areas. Surface soil particles showed little extent of alteration, with U speciated as oxides U₃O₇ and U₃O₈. Uranium oxidation state and crystalline phase mapping revealed these oxides occur as separate particles, reflecting heterogeneous formation conditions. Particles recovered from the disposal area were substantially weathered, and U(VI) phosphate phases such as meta-ankoleite (K(UO₂)(PO₄)路3H₂O) were dominant. Chemical imaging revealed domains of contrasting U oxidation state linked to the presence of both U₃O₇ and meta-ankoleite, indicating growth of a particle alteration layer. This study demonstrates that substantial alteration of DU residues can occur, which directly influences the health and environmental hazards posed by this contamination.