TY - GEN
T1 - Migration behavior of selenium in the presence of iron in bentonite
AU - Idemitsu, Kazuya
AU - Kozaki, Hikaru
AU - Akiyama, Daisuke
AU - Kishimoto, Masanao
AU - Yuhara, Masaru
AU - Maeda, Noriyuki
AU - Inagaki, Yaohiro
AU - Arima, Tatsumi
N1 - Publisher Copyright:
© 2014 Materials Research Society.
PY - 2014
Y1 - 2014
N2 - 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).
AB - 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).
UR - http://www.scopus.com/inward/record.url?scp=84908178898&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84908178898&partnerID=8YFLogxK
U2 - 10.1557/opl.2014.641
DO - 10.1557/opl.2014.641
M3 - Conference contribution
AN - SCOPUS:84908178898
T3 - Materials Research Society Symposium Proceedings
SP - 157
EP - 163
BT - Scientific Basis for Nuclear Waste Management XXXVII
A2 - Duro, Lara
A2 - Casas, Ignasi
A2 - de Pablo, Joan
A2 - Gimenez, Javier
PB - Materials Research Society
T2 - 37th International Symposium on the Scientific Basis for Nuclear Waste Management
Y2 - 29 September 2013 through 3 October 2013
ER -