Jump to ContentJump to Main Navigation
Show Summary Details
More options …

Radiochimica Acta

International Journal for chemical aspects of nuclear science and technology

Ed. by Qaim, Syed M.

12 Issues per year


IMPACT FACTOR 2016: 1.271
5-year IMPACT FACTOR: 1.286

CiteScore 2016: 1.20

SCImago Journal Rank (SJR) 2016: 0.486
Source Normalized Impact per Paper (SNIP) 2016: 0.761

Online
ISSN
2193-3405
See all formats and pricing
More options …
Volume 102, Issue 4 (Apr 2014)

Issues

TEM study of Green Rust Sodium Sulphate (GRNa,SO4) Interacted with Neptunyl Ions (NpO2+)

David Bach
  • Institute for Nuclear Waste Disposal, Karlsruhe Institute of Technology, P.O. Box 3640, 76021 Karlsruhe, Germany
/ Bo C. Christiansen
  • Nano-Science Center, Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø, Denmark
/ Dieter Schild
  • Corresponding author
  • Institute for Nuclear Waste Disposal, Karlsruhe Institute of Technology, P.O. Box 3640, 76021 Karlsruhe, Germany
  • Email:
/ Horst Geckeis
  • Institute for Nuclear Waste Disposal, Karlsruhe Institute of Technology, P.O. Box 3640, 76021 Karlsruhe, Germany
Published Online: 2014-03-14 | DOI: https://doi.org/10.1515/ract-2013-2105

Abstract

Green rust (GR) as sodium sulphate form, NaFe(II)6Fe(III)3(OH)18(SO4)2 · 12H2O, is reacted with an aqueous solution of neptunyl ions (NpO2+) and the resulting Np(IV) solid phase is investigated at a nanometer scale by different transmission electron microscopy (TEM) techniques, including high-resolution TEM (HRTEM), high-angle annular dark-field scanning TEM (HAADF-STEM), energy-dispersive X-ray spectroscopy (EDXS), and electron energy-loss spectroscopy (EELS). The aim of the analyses is to achieve insight into the potential immobilization mechanism for Np(V) in the context of safety assessment of a nuclear-waste repository. The neptunium is found to be immobilized at the edge of the green rust platelets, in a rim composed of nanocrystallites about 2–3.5 nm in size. The EELS results and more particularly the HRTEM findings are consistent with NpO2 crystallizing in a fluorite-type structure. Furthermore, the Np-O4,5 edges recorded by EELS at the Np(IV) phase are presented, expanding the EELS-data set currently available in the literature for Np.

Keywords: Green rust sodium sulphate; Neptunyl; Neptunium dioxide; Nuclear-waste repository; TEM; HRTEM; HAADF; EDXS; EELS; Np-O4,5 edges

About the article

Accepted: 2013-08-22

Received: 2013-02-08

Published Online: 2014-03-14

Published in Print: 2014-04-28


Citation Information: Radiochimica Acta, ISSN (Online) 2193-3405, ISSN (Print) 0033-8230, DOI: https://doi.org/10.1515/ract-2013-2105.

Export Citation

©2014 Walter de Gruyter Berlin/Boston. Copyright Clearance Center

Comments (0)

Please log in or register to comment.
Log in