...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Environmental Science & Technology >Adsorption of Selenium and Strontium on Goethite: EXAFS Study and Surface Complexation Modeling of the Ternary Systems
【24h】

Adsorption of Selenium and Strontium on Goethite: EXAFS Study and Surface Complexation Modeling of the Ternary Systems

机译：针铁矿上硒和锶的吸附：EXAFS研究和三元体系的表面络合模型

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Knowledge of the geochemical behavior of selenium and strontium is critical for the safe disposal of radioactive wastes. Goethite, as one of the most thermody-namically stable and commonly occurring natural iron oxy-hydroxides, promisingly retains these elements. This work comprehensively studies the adsorption of Se(IV) and Sr(II) on goethite. Starting from electrokinetic measurements, the binary and ternary adsorption systems are investigated and systematically compared via batch experiments, EXAFS analysis, and CD-MUSIC modeling. Se(IV) forms bidentate inner-sphere surface complexes, while Sr(ll) is assumed to form outer-sphere complexes at low and intermediate pH and inner-sphere complexes at high pH. Instead of a direct interaction between Se(IV) and Sr(ll), our results indicate an electrostatically driven mutual enhancement of adsorption. Adsorption of Sr(ll) is promoted by an average factor of 5 within the typical groundwater pH range from 6 to 8 for the concentration range studied here. However, the interaction between Se(IV) and Sr(II) at the surface is two-sided, Se(lV) promotes Sr(Il) outer-sphere adsorption, but competes for inner-sphere adsorption sites at high pH. The complexity of surfaces is highlighted by the inability of adsorption models to predict isoelectric points without additional constraints.
机译：了解硒和锶的地球化学行为对于安全处置放射性废物至关重要。针铁矿作为热力学最稳定，最常见的天然羟基氧化铁之一，有望保留这些元素。这项工作全面研究了针铁矿上Se（IV）和Sr（II）的吸附。从电动测量开始，对二元和三元吸附系统进行了研究，并通过批处理实验，EXAFS分析和CD-MUSIC建模系统地进行了比较。 Se（IV）形成双齿内球表面配合物，而Sr（II）则在低pH和中等pH时形成外球配合物，在高pH时形成内球配合物。我们的结果表明，静电驱动的相互吸附增强，而不是Se（IV）和Sr（II）之间的直接相互作用。对于此处研究的浓度范围，在典型的地下水pH范围6至8内，Sr（II）的吸附平均增加5。但是，Se（IV）和Sr（II）在表面的相互作用是双向的，Se（IV）促进Sr（II）外球的吸附，但在高pH下竞争内球的吸附位。吸附模型无法在没有其他约束的情况下预测等电点，凸显了表面的复杂性。

著录项

  • 来源
    《Environmental Science & Technology》 |2017年第7期|3751-3758|共8页
  • 作者

    Zhe Nie; Nicolas Finck; Frank Heberling; Tim Pruessmann; Chunli Liu; Johannes Lützenkirchen;

  • 作者单位

    Beijing National Laboratory for Molecular Sciences, Fundamental Science Laboratory on Radiochemistry and Radiation Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China,Institute for Nuclear Waste Disposal, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany;

    Institute for Nuclear Waste Disposal, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany;

    Institute for Nuclear Waste Disposal, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany;

    Institute of Catalysis Research and Technology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany,Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, Engesserstr. 20, 76131 Karlsruhe, Germany;

    Beijing National Laboratory for Molecular Sciences, Fundamental Science Laboratory on Radiochemistry and Radiation Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China;

    Institute for Nuclear Waste Disposal, Karlsruhe Institute of Technology, Hermann-von-Helmholtz Platz 1, 76344 Eggenstein-Leopoldshafen, Germany;

  • 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