Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-19T08:25:42.505Z Has data issue: false hasContentIssue false

Evaluation of Sorption Behavior of Iodide Ions on Calcium Silicate Hydrate and Hydrotalcite

Published online by Cambridge University Press:  08 April 2015

Taiji Chida
Affiliation:
Dept. of Quantum Science & Engineering, Graduate School of Engineering, Tohoku University, 6-6-01-2 Aramaki-aza-Aoba, Aoba-ku, Sendai 980-8579 JAPAN
Jun Furuya
Affiliation:
Dept. of Quantum Science & Engineering, Graduate School of Engineering, Tohoku University, 6-6-01-2 Aramaki-aza-Aoba, Aoba-ku, Sendai 980-8579 JAPAN
Yuichi Niibori
Affiliation:
Dept. of Quantum Science & Engineering, Graduate School of Engineering, Tohoku University, 6-6-01-2 Aramaki-aza-Aoba, Aoba-ku, Sendai 980-8579 JAPAN
Hitoshi Mimura
Affiliation:
Dept. of Quantum Science & Engineering, Graduate School of Engineering, Tohoku University, 6-6-01-2 Aramaki-aza-Aoba, Aoba-ku, Sendai 980-8579 JAPAN
Get access

Abstract

The migration retardation of anionic radionuclides, notably I-129, in radioactive waste repositories is one of the most critical factors for improving the performance of engineered barriers. To gain more fundamental knowledge required to make such improvements, this study examined the sorption behavior of iodide ions on calcium silicate hydrate (CSH) and hydrotalcite (HT), which act as anion exchangers. CSH was synthesized using CaO and fumed silica, with Ca/Si molar ratios ranging from 0.4 to 1.6. The weight ratio of CSH to HT was 1.0. These solid samples were immersed for 14 days in a 30 mL sample of pure water or 0.6 M NaCl solution, each of which contained 0.5 mM iodide ions with a given liquid/solid weight ratio (10, 15, or 20). Raman spectroscopy studies indicated that the structures of CSH and HT were maintained during the hydration of the solid phase and the sorption of iodide ions. The distribution coefficients for the sorption of iodide ions on CSH and HT ranged from 6 to 13 L/kg for pure water and from 1 to 2 L/kg for NaCl solution. These retardation effects for iodide ions would contribute toward improving the performance of the repository system as most conventional safety assessments assume that iodide ions hardly sorb on engineered barriers such as cementitious materials.

Type
Articles
Copyright
Copyright © Materials Research Society 2015 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

JNC (Japan Nuclear Cycle development institute), H12 Project to Establish the Scientific and Technical Basis for HLW Disposal in Japan Vol. 3, JNC TN1400 99 (1999).Google Scholar
Furuya, J., Chida, T., Niibori, Y. and Mimura, H., Proc. of WM 2014 Conference, Paper No. 14077 (2014).Google Scholar
Borrmann, T., Johnson, J.H., McFarlane, A.J., Richardson, M.J. and O’Connor, S.J., J. Colloid Interface Sci., 339, 175182 (2009).CrossRefGoogle Scholar
Parker, L.M., Milestone, N.B., Newman, R.H., Ind. Eng. Chem. Res., 34, 11961202 (1995).CrossRefGoogle Scholar
Miyata, S., Clays Clay Mineral., 31, 305311 (1983).CrossRefGoogle Scholar
Funabashi, T., Niibori, Y. and Mimura, H., Proc. of WM 2012 Conference, Paper No. 12145 (2012).Google Scholar
Kirkpatrick, R.J., Yarger, J.L., McMillan, P.F., Yu, P. and Cong, X., Adv. Cem. Based Mater., 5, 9399 (1997).CrossRefGoogle Scholar
Burrueco, M.I., Mora, M., Jimenez-Sanchidrian, C. and Ruiz, J.R., J. Mol. Struct., 1034, 3842 (2013).CrossRefGoogle Scholar
Salam, M.A., Sufian, S. and Murugesan, T., Mater. Chem. Phys., 142, 213219 (2013).CrossRefGoogle Scholar