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Title: The corrosion behavior of technetium metal exposed to aqueous sulfate and chloride solutions

Abstract

Here, metal waste forms are being studied as possible disposal forms for technetium and other fission products from spent nuclear fuel. As an initial step in assessing the viability of waste forms, technetium corrosion and passivity behavior was assessed across a broad pH spectrum (pH –1 to pH 13). Measurements indicate that the open circuit potential falls into the region of Tc +7 stability, more noble than the region of presumed passivity. Potentiodynamic polarization tests indicate that the Tc samples are not passive. Both electrochemical results and visual inspection suggest the presence of a nonprotective film. The corrosion rate is relatively independent of pH and low, as measured by linear polarization resistance. No evidence of passivity was observed in the Tc +4 region of the potential-pH diagram following in-situ abrasion, suggesting that Tc does not passivate, regardless of potential.

Authors:
 [1]; ORCiD logo [1];  [1]; ORCiD logo [1];  [1];  [2];  [2]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Univ. of Nevada, Las Vegas, NV (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Nuclear Energy (NE). Nuclear Reactor Technologies (NE-7)
OSTI Identifier:
1358171
Report Number(s):
LA-UR-17-21185
Journal ID: ISSN 0013-4651
Grant/Contract Number:
AC52-06NA25396
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of the Electrochemical Society
Additional Journal Information:
Journal Volume: 164; Journal Issue: 6; Journal ID: ISSN 0013-4651
Publisher:
The Electrochemical Society
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; corrosion; technetium

Citation Formats

Kolman, David Gary, Goff, George Scott, Cisneros, Michael Ruben, Boland, Kevin Sean, Jarvinen, Gordon, Poineau, Frederic, and Czerwinski, Ken. The corrosion behavior of technetium metal exposed to aqueous sulfate and chloride solutions. United States: N. p., 2017. Web. doi:10.1149/2.1561706jes.
Kolman, David Gary, Goff, George Scott, Cisneros, Michael Ruben, Boland, Kevin Sean, Jarvinen, Gordon, Poineau, Frederic, & Czerwinski, Ken. The corrosion behavior of technetium metal exposed to aqueous sulfate and chloride solutions. United States. doi:10.1149/2.1561706jes.
Kolman, David Gary, Goff, George Scott, Cisneros, Michael Ruben, Boland, Kevin Sean, Jarvinen, Gordon, Poineau, Frederic, and Czerwinski, Ken. Wed . "The corrosion behavior of technetium metal exposed to aqueous sulfate and chloride solutions". United States. doi:10.1149/2.1561706jes. https://www.osti.gov/servlets/purl/1358171.
@article{osti_1358171,
title = {The corrosion behavior of technetium metal exposed to aqueous sulfate and chloride solutions},
author = {Kolman, David Gary and Goff, George Scott and Cisneros, Michael Ruben and Boland, Kevin Sean and Jarvinen, Gordon and Poineau, Frederic and Czerwinski, Ken},
abstractNote = {Here, metal waste forms are being studied as possible disposal forms for technetium and other fission products from spent nuclear fuel. As an initial step in assessing the viability of waste forms, technetium corrosion and passivity behavior was assessed across a broad pH spectrum (pH –1 to pH 13). Measurements indicate that the open circuit potential falls into the region of Tc+7 stability, more noble than the region of presumed passivity. Potentiodynamic polarization tests indicate that the Tc samples are not passive. Both electrochemical results and visual inspection suggest the presence of a nonprotective film. The corrosion rate is relatively independent of pH and low, as measured by linear polarization resistance. No evidence of passivity was observed in the Tc+4 region of the potential-pH diagram following in-situ abrasion, suggesting that Tc does not passivate, regardless of potential.},
doi = {10.1149/2.1561706jes},
journal = {Journal of the Electrochemical Society},
number = 6,
volume = 164,
place = {United States},
year = {Wed Apr 19 00:00:00 EDT 2017},
month = {Wed Apr 19 00:00:00 EDT 2017}
}

Journal Article:
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