RETENTION OF REDOX-SENSITIVE ELEMENTS IN AQUIFERS - THE CASE OF NEPTUNIUM

被引：12
作者：
DEGUELDRE, C
机构：
[1] Paul Scherrer Institute
来源：
JOURNAL OF ENVIRONMENTAL RADIOACTIVITY | 1995年 / 29卷 / 01期
关键词：
D O I：
10.1016/0265-931X(95)00021-2
中图分类号：
X [环境科学、安全科学];
学科分类号：
08 ; 0830 ;
摘要：
An original development based on a surface complexation model allows Kd calculations as a function of the redox potential. Neptunium is studied because its redox chemistry is complex due to the presence of various valence states ranging from Np(III) to Np(VII). Its sorption on SiO2, FeOOH and Al2O3 is calculated as a function of the redox potential for different pHs using a simplified surface complexation model. Calculated K-d values are consistent with the experimental K-d data from the literature for Np or analogous species (Am(III), Th(IV), U(VI)) at pH8. The neptunium retention in aquifers may then be evaluated on the basis of their porosity properties.
引用
收藏
页码：75 / 87
页数：13
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