Migration behavior of selenium in the presence of iron in bentonite

Kazuya Idemitsu, Hikaru Kozaki, Daisuke Akiyama, Masanao Kishimoto, Masaru Yuhara, Noriyuki Maeda, Yaohiro Inagaki, Tatsumi Arima

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

Selenium (Se) is an important element for assessing the safety of high-level waste disposal. Se is redox-sensitive, and its oxidation state varies from -2 to 6 depending on the redox conditions and pH of the solution. Large quantities of ferrous ions formed in bentonite due to corrosion of carbon steel overpack after the closure of a repository are expected to maintain a reducing environment near the repository. Therefore, the migration behavior of Se in the presence of Fe in bentonite was investigated by electrochemical experiments. Na2SeO3 solution was used as tracer solution. Dry density range of bentonite was from 0.8 to 1.4 × 103kg/m3. Results indicated that Se was strongly retained by the processes such as precipitation reaction with ferrous ions in bentonite. Se K-edge X-ray absorption near-edge structure (XANES) measurements were performed at the BL-11 beamline at SAGA Light Source, and the results revealed that the oxidation state of Se in the bentonite remained Se(IV).

Original languageEnglish
Title of host publicationScientific Basis for Nuclear Waste Management XXXVII
EditorsLara Duro, Ignasi Casas, Joan de Pablo, Javier Gimenez
PublisherMaterials Research Society
Pages157-163
Number of pages7
ISBN (Electronic)9781605116426
DOIs
Publication statusPublished - Jan 1 2014
Event37th International Symposium on the Scientific Basis for Nuclear Waste Management - Barcelona, Spain
Duration: Sep 29 2013Oct 3 2013

Publication series

NameMaterials Research Society Symposium Proceedings
Volume1665
ISSN (Print)0272-9172

Other

Other37th International Symposium on the Scientific Basis for Nuclear Waste Management
CountrySpain
CityBarcelona
Period9/29/1310/3/13

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All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Idemitsu, K., Kozaki, H., Akiyama, D., Kishimoto, M., Yuhara, M., Maeda, N., ... Arima, T. (2014). Migration behavior of selenium in the presence of iron in bentonite. In L. Duro, I. Casas, J. de Pablo, & J. Gimenez (Eds.), Scientific Basis for Nuclear Waste Management XXXVII (pp. 157-163). (Materials Research Society Symposium Proceedings; Vol. 1665). Materials Research Society. https://doi.org/10.1557/opl.2014.641