A Spectroscopic Characterization and Quantification of M(III)/Clay Mineral Outer-Sphere Complexes

详细信息    查看全文

• 作者：Eva Hartmann ; Bart Baeyens ; Michael H. Bradbury ; Horst Geckeis ; Thorsten Stumpf
• 刊名：Environmental Science & Technology
• 出版年：2008
• 出版时间：October 15, 2008
• 年：2008
• 卷：42
• 期：20
• 页码：7601-7606
• 全文大小：192K
• 年卷期：v.42,no.20(October 15, 2008)
• ISSN：1520-5851

文摘

For the long-term safety assessment of deep radioactive waste repositories an understanding of the interactions of actinides with mineral surfaces at a molecular level is necessary. The retention/mobility of the released radionuclides is strongly dependent on sorption/desorption reactions at mineral surfaces. Thus, a quantitative understanding of the uptake mechanisms of actinides on clay minerals will make an important contribution to long-term safety assessments. Using time-resolved laser fluorescence spectroscopy (TRLFS), it was possible to differentiate between nonsorbed aquo ions and outer-sphere sorbed Cm(III) onto different montmorillonites. In addition, Cm(III)/clay outer-sphere complexation at different ionic strengths using NaCl as the background electrolyte is quantified. Finally, the results are verified by sorption model calculations.