放射性捕获在含有银的mordenites通过纳米尺度的银化物形成
Karena W Chapman1, Peter J Chupas, Tina M Nenoff
1X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA. chapmank@aps.anl.gov
Journal of the American Chemical Society
|June 17, 2010
概括
有效捕获放射性 ((129) I) 对核废物储存至关重要. 没有减少的白银交换的摩登石将限制在毛孔内,为放射性的捕获和长期存储提供了更安全的方法.
科学领域:
- 材料科学 材料科学 材料科学
- 核化学 核化学 核化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 捕获和储存放射性 ((129) I) 对核废物管理和核能安全至关重要.
- 含银的摩登石 (MOR) 是一种成熟的捕获材料,但其在分子层面的机制尚未完全理解.
- 开发改进的获取器需要更深入地了解摩登石中吸附过程.
研究的目的:
- 为了阐明的结构和分布,由含有银的摩登石 (MOR) 吸收.
- 为了比较减少与未减少的吸附与白银交换的MOR.
- 确定安全捕获放射性的最佳条件.
主要方法:
- 差异对分布函数分析被用来探测含银MOR吸收的的结构.
- 该研究调查了减少和未减少的白银交换MOR样本.
- 描述的重点是在摩登石结构中的位置和形式.
主要成果:
- 在减少的银MOR中,在表面的玛-AgI纳米粒子和毛孔内的α-AgI集群之间分布.
- 在未减少的白银交换MOR中,仅限于以亚纳米α-AgI集群的形式限制在毛孔内.
- 这种限制在未减少的MOR中表明一种更稳定的封存机制.
结论:
- 没有减少的白银交换的化物为放射性捕获提供了更安全的途径.
- 在未减少的MOR中,的独特孔隙封闭增强了其有效长期放射性废物储存的潜力.
- 了解在分子水平上的分布是设计优质获取器的关键.
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