...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Environmental Science & Technology >U(VI) Reduction by Biogenic and Abiotic Hydroxycarbonate Green Rusts: Impacts on U(IV) Speciation and Stability Over Time
【24h】

U(VI) Reduction by Biogenic and Abiotic Hydroxycarbonate Green Rusts: Impacts on U(IV) Speciation and Stability Over Time

机译：U（VI）通过生物和非生物碳酸氢盐绿锈的还原：对U（IV）形态和稳定性的影响

获取原文
获取原文并翻译 | 示例
   

获取外文期刊封面封底 >>

       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Green rusts (GRs) are redox active Fe~(II)–Fe~(III) minerals that form in the environment via various biotic and abiotic processes. Although both biogenic (BioGR) and abiotic (ChemGR) GRs have been shown to reduce U~(VI), the dynamics of the transformations and the speciation and stability of the resulting U~(IV) phases are poorly understood. We used carbonate extraction and XAFS spectroscopy to investigate the products of U~(VI) reduction by BioGR and ChemGR. The results show that both GRs can rapidly remove U~(VI) from synthetic groundwater via reduction to U~(IV). The initial products in the ChemGR system are solids-associated U~(IV)–carbonate complexes that gradually transform to nanocrystalline uraninite over time, leading to a decrease in the proportion of carbonate-extractable U from ∼95% to ∼10%. In contrast, solid-phase U~(IV) atoms in the BioGR system remain relatively extractable, nonuraninite U~(IV) species over the same reaction period. The presence of calcium and carbonate in groundwater significantly increase the extractability of U~(IV) in the BioGR system. These data provide new insights into the transformations of U under anoxic conditions in groundwater that contains calcium and carbonate, and have major implications for predicting uranium stability within redox dynamic environments and designing approaches for the remediation of uranium-contaminated groundwater.
机译：绿锈（GRs）是氧化还原活性的Fe〜（II）–Fe〜（III）矿物质，通过多种生物和非生物过程在环境中形成。尽管已证明生物（GR）和非生物（GR）GR均能降低U〜（VI），但人们对转化的动力学以及所形成的U〜（IV）相的形态和稳定性却知之甚少。我们使用碳酸盐萃取和XAFS光谱研究了BioGR和ChemGR还原U〜（VI）的产物。结果表明，两种GRs都可以通过还原为U〜（IV）来快速去除合成地下水中的U〜（VI）。 ChemGR系统的初始产物是与固体相关的U〜（IV）-碳酸盐配合物，随着时间的推移，这些配合物逐渐转变为纳米晶的尿素，导致可萃取碳酸盐的U的比例从约95％降至约10％。相比之下，BioGR系统中的固相U〜（IV）原子在相同的反应期间内仍是相对可萃取的非铀矿U〜（IV）物种。地下水中钙和碳酸盐的存在显着提高了BioGR系统中U〜（IV）的可萃取性。这些数据为含钙和碳酸盐的地下水在缺氧条件下U的转化提供了新的见解，并且对预测氧化还原动态环境中的铀稳定性以及设计修复受铀污染的地下水的方法具有重要意义。

著录项

  • 来源
    《Environmental Science & Technology》 |2018年第8期|4601-4609|共9页
  • 作者

    Sen Yan; Maxim I. Boyanov; Bhoopesh Mishra; Kenneth M. Kemner; Edward J. O’Loughlin;

  • 作者单位

    School of Earth Sciences, China University of Geosciences, Wuhan, 430074, China,Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439, United States;

    Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439, United States,Institute of Chemical Engineering, Bulgarian Academy of Sciences, Sofia, 1113, Bulgaria;

    Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439, United States,School of Chemical and Process Engineering, University of Leeds, Leeds, LS2 9JT, U.K.;

    Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439, United States;

    Biosciences Division, Argonne National Laboratory, Argonne, Illinois 60439, United States;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号