Export file:


  • RIS(for EndNote,Reference Manager,ProCite)
  • BibTex
  • Text


  • Citation Only
  • Citation and Abstract

Electrochemical Cs removal and crystal formation from Fukushima weathered biotite in molten NaCl-CaCl2

1 Materials Sciences Research Center (MSRC), Japan Atomic Energy Agency (JAEA), 2-4, Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195, Japan
2 Department of Science of Environment and Mathematical Modeling, Graduate School of Science and Engineering, Doshisha University, Kyoto, 610-0321, Japan
3 Fukushima Environmental Safety Center, Japan Atomic Energy Agency (JAEA), 6-6 Sakae-machi, Fukushima-shi, Fukushima 960-8031, Japan

The possibility of removal and controlling crystal formation from weathered biotite (WB) in clay minerals were investigated using molten salt electrochemistry (EC) in molten NaCl-CaCl2 under an electrochemical reductive reaction. Cyclic Voltammogram (CV) measurements were performed in the range of +0.5 V to −2.2 V. Several peaks were confirmed in the CV spectra. The peak at −1.4 V represents a reduction reaction of Fe in WB, so we conducted an experiment at −1.4 V for 2 h to reduce Iron (Fe). The Cs removal rate after EC treatment was determined by X-ray fluorescence analysis, and almost 100% Cs removal was confirmed. To understand the effect of the reductive reaction, we performed X-ray Adsorption Fine Structure (XAFS) analysis. Before EC treatment, the Fe in WB was present as a mixture of Fe3+ and Fe2+. After EC treatment, the presence of Fe2+ was confirmed by XAFS analysis. Based on this finding, EC treatment is effective for reducing Fe in WB. This result indicated that Fe2O3 formation was suppressed, and the reduction reaction was effective for controlling crystal formation.
  Article Metrics

Keywords molten salt; electrochemistry; X-ray analysis; Fe; clay mineral

Citation: M. Honda, T. Goto, Y. Sakanaka, T. Yaita, S. Suzuki. Electrochemical Cs removal and crystal formation from Fukushima weathered biotite in molten NaCl-CaCl2. AIMS Electronics and Electrical Engineering, 2019, 3(2): 102-110. doi: 10.3934/ElectrEng.2019.2.102


  • 1. Sawhney BL (1972) SELECTIVE SORPTION AND FIXATION OF CATIONS BY CLAY MINERALS: A REVIEW. Clays and Clay Minerals 20: 93–100.    
  • 2. Francis CW and Brinkley FS (1976) Preferential adsorption of 137Cs to micaceous minerals in contaminated freshwater sediment. Nature 260: 511–513.    
  • 3. Cornell RM (1993) Adsorption of cesium on minerals: A review. J Radioanal Nucl Ch 171: 483–500.    
  • 4. Hird AB, Rimmer DL and Livens FR (1995) Total Caesium-Fixing Potentials of Acid Organic Soils. J Environ Radioact 26: 103–118.    
  • 5. Ohnuki T and Kozai N (2013) Adsorption behavior of radioactive cesium by non-mica minerals. J Nucl Sci Technol 50: 369–375.    
  • 6. Morino Y, Ohara T and Nishizawa M (2011) Atmospheric behavior, deposition, and budget of radioactive materials from the Fukushima Daiichi nuclear power plant in March 2011. Geophys Res Lett 38: L00G11.
  • 7. Kawamura H, Kobayashi T, Teiji AF (2011) In: Y. Ishikawa, T. Nakayama, S. Shima, et al. Preliminary numerical experiments of 131I and 137Cs discharged into the ocean because of the Fukushima Daiichi nuclear power plant disaster. J Nucl Sci Technol 48: 1349–1356.
  • 8. Strand P, Aono T, Brown JE, et al. (2014) Assessment of Fukushima-Derived Radiation Doses and Effects on Wildlife in Japan. Environ Sci Technol 1: 198–203.    
  • 9. Honma K, Takano H, Miura K, et al. (2014) Removal of Cs from the soil contaminated with
  • radioactive materials by heat treatment. Nendo Kagaku 52: 71–73
  • 10. Mukai H, Hirose A, Motai S, et al. (2016) Cesium adsorption/desorption behavior of clay minerals considering actual contamination conditions in Fukushima. Sci Rep 6: 21543.    
  • 11. Honda M, Okamoto Y, Shimoyama I, et al. (2017) Mechanism of Cs Removal from Fukushima Weathered Biotite by Heat Treatment with a NaCl–CaCl2 Mixed Salt. ACS Omega 2: 721–727.    
  • 12. Honda M, Shimoyama I, Kogure T, et al. (2017) Proposed Cesium-free Mineralization Method for Soil Decontamination: Demonstration of Cesium Removal from Weathered Biotite. ACS Omega 2: 8678–8681.    
  • 13. Kikuchi R, Mukai H, Kuramata C, et al. (2015) Cs-sorption in weathered biotite from Fukushima granitic soil. J Mineral Petrol Sci 110: 126–134.    
  • 14. Wilke M, Frages F, Petit P-E, et al. (2001) Oxidation state and coordination of Fe in minerals: An Fe K-XANES spectroscopic study. Am Mineral 86: 714–730.    
  • 15. Westre TE, Kennepohl P, DeWitt JG, et al. (1997) A multiplet analysis of Fe K-Edge 1s → 3d pre-edge features of iron complexes. J Am Chem Soc 119: 6297–6314.    


Reader Comments

your name: *   your email: *  

© 2019 the Author(s), licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution Licese (http://creativecommons.org/licenses/by/4.0)

Download full text in PDF

Export Citation

Copyright © AIMS Press All Rights Reserved