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Radiochimica Acta

International Journal for chemical aspects of nuclear science and technology

Editor-in-Chief: Qaim, Syed M.

IMPACT FACTOR 2018: 1.339

CiteScore 2018: 1.20

SCImago Journal Rank (SJR) 2018: 0.333
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Volume 107, Issue 7


Modeling the sorption of Np(V) on Na-montmorillonite – effects of pH, ionic strength and CO2

Raphael Scholze
  • Institute of Nuclear Chemistry, Johannes Gutenberg-Universität Mainz, Fritz-Strassmann-Weg 2, 55128 Mainz, Germany
  • Other articles by this author:
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/ Samer Amayri
  • Institute of Nuclear Chemistry, Johannes Gutenberg-Universität Mainz, Fritz-Strassmann-Weg 2, 55128 Mainz, Germany
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Tobias Reich
  • Corresponding author
  • Institute of Nuclear Chemistry, Johannes Gutenberg-Universität Mainz, Fritz-Strassmann-Weg 2, 55128 Mainz, Germany, Phone: +49 6131 39 25250, Fax: +49 6131 39 27250
  • Email
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Published Online: 2019-05-27 | DOI: https://doi.org/10.1515/ract-2019-3109


Results from batch type experiments were modeled using the 2 SPNE SC/CE model developed by Bradbury and Baeyens. This work focused on the applicability of this model to the sorption of Np(V) on Na-montmorillonite under high saline conditions (0.1–3.0 M NaCl) in the pH range of 2–10 and in the presence of dissolved CO2 (p(CO2) = 10−3.3 atm). Under ambient air conditions two additional surface complexation species had to be taken into account, which are ternary species involving one carbonate ligand (≡SONpO2(CO3)2−, ≡SONpO2(CO3)Na). The gained set of complexation parameters was successfully tested over a wide range of Np(V) concentrations (10−4 to 10−12 M) under Ar atmosphere and ambient air condition.

Keywords: Neptunium; Np(V); montmorillonite; sorption; modeling; 2 SPNE SC/CE

Dedicated to: The memory of Prof. Dr. Günter Herrmann.


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About the article

Received: 2019-01-22

Accepted: 2019-04-24

Published Online: 2019-05-27

Published in Print: 2019-07-26

Citation Information: Radiochimica Acta, Volume 107, Issue 7, Pages 615–622, ISSN (Online) 2193-3405, ISSN (Print) 0033-8230, DOI: https://doi.org/10.1515/ract-2019-3109.

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