Abstract
Bentonite, a natural clay, is a promising candidate to be used as a buffer/backfill material in the geological disposal systems for management of high level waste (HLW). Fe released due to corrosion of canister/overpack may result in alteration of Na-montmorillonite (Na-Mt), present in bentonite, to Fe-montmorillonite (Fe-Mt) in a span of several years after the emplacement of vitrified HLW in deep geological repositories. For realistic performance assessment, it is essential to understand the sorption behavior of altered Mt with regard to the radionuclides present in HLW. Cs is one of the high-yield (137Cs t1/2 = 30.1 y, 6%) and long-lived (135Cs t1/2 = 2 × 106 y) fission products in spent fuels. The objective of present study is to understand the effect of various parameters, viz., time (0–48 h), pH (3.0–9.0), ionic strength (0.001–1 M) [Cs(I)] (10−10–10−3 M) and Fe dissolution on sorption behavior of Cs(I) on Fe(II)-Mt through batch sorption experiments. Fe(II)-Mt was synthesized by reducing Fe(III)-Mt using ascorbic acid as reducing agent in N2 atmosphere. The near-constancy in Cs(I) sorption on Fe(II)-Mt with pH (≥4), and decrease with increasing ionic strength, illustrate the ion exchange as dominant mode of Cs(I) sorption. Further, Cs(I) sorption isotherm on Fe(II)-Mt is found to be linear. The estimation of dissolved iron in the supernatant of Fe(II)-Mt suspensions demonstrated that dissolved Fe decreased with increase in pH and increased with increase in ionic strength. Moreover, the Fe2+/Fetotal ratio determined in all experiments was close to unity, thereby depicting that Fe(II) did not oxidize to Fe(III), except when suspension pH was ≥ 5.5. For comparison, Cs(I) sorption was also studied on Na(I)-Mt and compared with that on Fe(III)-Mt. Surface complexation modeling of Cs(I) sorption on the three clay minerals, viz., Na-Mt, Fe(II)-Mt and Fe(III)-Mt, has been successfully carried out.
Funding source: Board of Research in Nuclear Sciences
Award Identifier / Grant number: 37(2)/14/20/2015/BRNS
Funding source: Department of Atomic Energy, Government of India
Award Identifier / Grant number: SR/FST/CSI-273/2016
Acknowledgments
Authors greatly acknowledge the financial support from BRNS/DAE [No. 37(2)/14/20/2015/BRNS, Dt: 27/07/2015] and DST-FIST, Ministry of Science and Technology [No. SR/FST/CSI-273/2016], Govt. of India. Dr. B. S. Tomar acknowledges the support from DAE towards Raja Ramanna Fellowship.
Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: Authors greatly acknowledge the financial support from BRNS/DAE [No. 37(2)/14/20/2015/BRNS, Dt: 27/07/2015] and DST-FIST, Ministry of Science and Technology [No. SR/FST/CSI-273/2016], Govt. of India. Dr. B. S. Tomar acknowledges the support from DAE towards Raja Ramanna Fellowship.
Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
References
1. Manolopoulou, M., Stoulos, S., Ioannidou, A., Vagena, E., Papasterfanou, C. Radioecological indexes of fall out measurements from the Fukushima nuclear accident. Ecol. Indicat. 2013, 25, 197; https://doi.org/10.1016/j.ecolind.2012.09.016.Search in Google Scholar
2. Missana, T., Benedicto, A., Garcia-Gutierez, M., Alonso, U. Modeling cesium retention onto Na−, K− and Ca−smectite: effects of ionic strength, exchange and competing cations on the determination of selectivity coefficients. Geochem. Cosmochim. Acta 2014a, 128, 266; https://doi.org/10.1016/j.gca.2013.10.007.Search in Google Scholar
3. Durrant, C. B., Beggi, J. D., Kersting, A. B., Zavarin, M. Cesium sorption reversibility and kinetics on illite, montmorillonite and kaolinite. Sci. Total Environ. 2018, 511, 610–611; https://doi.org/10.1016/j.scitotenv.2017.08.122.Search in Google Scholar
4. PNC. Research and development on geological disposal of high-level radioactive waste: first progress report (H3); PNCTN 1410 93-059, 1992.Search in Google Scholar
5. Pusch, R. The buffer and backfill handbook part 2: materials and techniques; SKB TR-02-12; Svensk Karnbrinslehantering AB, 2001; pp. 11−12.Search in Google Scholar
6. Japan Nuclear Cycle Development Institute. H12: project to establish the scientific and technical basis for HLW disposal in Japan. JNC TN1410 2000-003, 2000.Search in Google Scholar
7. Nagra Project Opalinus Clay. Safety report Nagra technical report 02-05; Nagra: Wettingen, 2002; p. 718.Search in Google Scholar
8. Cornell, R. M. Adsorption of cesium on minerals: a review. J. Radioanal. Nucl. Chem. 1993, 171, 483; https://doi.org/10.1007/bf02219872.Search in Google Scholar
9. Tsai, S. C., Ouyang, S., Hsu, C. N. Sorption and diffusion behavior of Cs and Sr on Jih-Hsing bentonite. Appl. Radiat. Isot. 2001, 54, 209; https://doi.org/10.1016/s0969-8043(00)00292-x.Search in Google Scholar
10. Wanner, H., Albinsson, Y., Wieland, E. A thermodynamic surface model for caesium sorption on bentonite. J. Anal. Chem. 1996, 354, 763; https://doi.org/10.1007/s0021663540763.Search in Google Scholar
11. Atun, G., Bilgin, B., Mardinli, A. Sorption of cesium on montmorillonite and effects of salt concentration. J. Radioanal. Nucl. Chem. 1996, 11, 425; https://doi.org/10.1007/bf02039708.Search in Google Scholar
12. Idemitsu, k., Yano, S., Xia, X., Kikuchi, Y., Inagaki, Y., Arima, T. Migration behavior of iron in compacted bentonite under reducing condition using electromigration. Mater. Res. Soc. Symp. Proc. 2003, 757, II3.7.1–II3.7.8.10.1557/PROC-757-II3.7Search in Google Scholar
13. Kamei, G., Oda, C., S., Shibata, M., Shinozaki, T. Fe(II)−Na ion exchange at interlayers of smectite: adsorption-desorption experiments and a natural analogue. Eng. Geol. 1999, 54, 15; https://doi.org/10.1016/s0013-7952(99)00057-5.Search in Google Scholar
14. Wilson, J., Savage, D., Cuadros, J., Shibata, M., Ragnarsdottir, K. V. The effect of iron on bentonite stability: (I) background and thermodynamic considerations. Geochem. Cosmochim. Acta. 2006a, 70, 306; https://doi.org/10.1016/j.gca.2005.10.003.Search in Google Scholar
15. Wilson, J., Cressey, G., Cressey, B., Cuadros, J., Ragnarsdottir, K. V., Savage, D., Shibata, M. The effect of iron on montmorillonite stability. (I) Experimental investigations. Geochem. Cosmochim. Acta. 2006b, 70, 323; https://doi.org/10.1016/j.gca.2005.09.023.Search in Google Scholar
16. Guillaume, D., Neaman, A., Cathelineau, M., Mosser-Ruck, R., Pfeiffert, C., Abdeloula, M., Dubessy, J., Villeras, F., Baronnet, A., Michau, N. Experimental synthesis of chlorite from smectite at 300 °C in the presence of metallic Fe. Clay Miner. 2003, 38, 281; https://doi.org/10.1180/0009855033830096.Search in Google Scholar
17. Guillaume, D., Neaman, A., Cathelineau, M., Mosser-Ruck, R., Pfeiffert, C., Abdelmoula, M., Dubessy, J., Villieras, F., Michau, N. Experimental study of the transformation of smectite at 80 and 300°C in the presence of Fe oxides. Clay Miner. 2004, 39, 17; https://doi.org/10.1180/0009855043910117.Search in Google Scholar
18. Cathelineau, M., Guillaume, D., Mosser-Ruck, R., Dubessy, J., Charpentier, D., Villieras, F., Michau, N. Dissolution–crystallization processes affecting di-octahedral smectite in presence of iron metal: implication on mineral distribution in clay barriers. In International Meeting on Clays in Natural and Engineered Barriers for Radioactive Waste Confinement; Tours: France, 2005; p. 35.Search in Google Scholar
19. Cathelineau, M., Mosser-Ruck, R., Rousset, D., Guillaume, D., Charpentier, D., Devineau, K., Villieras, F., Michau, N. Effects of temperature, pH, iron/clay ratio and liquid/clay ratio on the conversion of di−octahedral smectite into iron−rich clays: a review of experimental studies. In International Meeting on Clays in Natural and Engineered Barriers for Radioactive Waste Confinement; Lille: France, 2007; p. 103.Search in Google Scholar
20. Mosser-Ruck, R., Cathelineau, M., Guillaume, D., Charpentier, D., Rousset, D., Bares, O., Michau, N. Effects of temperature, pH, and iron/clay and liquid/clay ratios on experimental conversion of di−octahedral smectite to berthierine, chlorite, vermiculite, or saponite. Clay Clay Miner. 2010, 58, 280; https://doi.org/10.1346/ccmn.2010.0580212.Search in Google Scholar
21. Herrera, R., Peech, M. Reaction of montmorillonite with iron (III). Proc. Soil Sci. Soc. Am. 1970, 34, 740; https://doi.org/10.2136/sssaj1970.03615995003400050021x.Search in Google Scholar
22. Valverde, J. L., Romero, A., Romero, R., Garcia, P. B., Sanchez, M. L., Ascenio, I. Preparation and characterization of Fe-PILCS. Influence of the synthesis parameters. Clays Clay Miner. 2005, 53, 613; https://doi.org/10.1346/ccmn.2005.0530607.Search in Google Scholar
23. Manjanna, J., Kozaki, T., Kozai, N., Sato, S. A new method for Fe(II)-montmorillonite preparation using Fe(II)-nitrilotriacetate complex. J. Nucl. Sci. Technol. 2007, 44, 929; https://doi.org/10.1080/18811248.2007.9711331.Search in Google Scholar
24. Vinoda, B. M., Manjanna, J. Dissolution of iron in salicylic acid and cation exchange between Fe(II)-salicylate and Na-montmorillonite to form Fe(II)-montmorillonite. Appl. Clay Sci. 2014, 78, 97–98; https://doi.org/10.1016/j.clay.2014.05.005.Search in Google Scholar
25. Manjanna, J. Preparation of Fe(II)-montmorillonite by reduction of Fe(III)-montmorillonite with ascorbic acid. Appl. Clay Sci. 2008, 42, 32; https://doi.org/10.1016/j.clay.2008.02.005.Search in Google Scholar
26. Chikkamath, S., Madhuri, A. P., Kar, A. S., Vaibhavi, R., Tomar, B. S., Manjanna, J. Sorption of Eu(III) on Fe-montmorillonite relevant to geological disposal of HLW. Radiochim. Acta 2018, 106, 97; https://doi.org/10.1515/ract-2018-2947.Search in Google Scholar
27. Manjanna, J., Kozaki, T., Sato, S. Fe(III)-montmorillonite: basic properties and diffusion of tracers relevant to alteration of bentonite in deep geological disposal. Appl. Clay Sci. 2009, 43, 208; https://doi.org/10.1016/j.clay.2008.09.007.Search in Google Scholar
28. Chakraborty, S., Bovin, F., Bannerjee, D., Scheinost, A., Mullet, M., Ehrardt, J. J., Brendle, J., Vidal, L., Charlet, L. Uranium(VI) sorption and reduction by Fe(II) sorbed on montmorillonite. Environ. Sci. Technol. 2010, 44, 3779; https://doi.org/10.1021/es903493n.Search in Google Scholar PubMed
29. Lu, S., Tan, X., Yu, S., Ren, X., Chen, C. Characterization of Fe(III)-saturated montmorillonite and evaluation its sorption behavior for U(VI). Radiochim. Acta 2016, 104, 481; https://doi.org/10.1515/ract-2015-2569.Search in Google Scholar
30. Chikkamath, S., Patel, M. A., Kar, A. S., Raut, V., Tomar, B. S., Manjanna, J. Sorption and diffusion of Cs(I) on Fe(III)-montmorillonite. Radiochim. Acta 2019, 107, 387; https://doi.org/10.1515/ract-2018-3016.Search in Google Scholar
31. Cherif, M. A., Martin-Garin, A., Gerard, F., Bildstein, O. A robust and parsimonious model for caesium sorption on clay minerals and natural clay materials. Appl. Geochem. 2017, 87, 22; https://doi.org/10.1016/j.apgeochem.2017.10.017.Search in Google Scholar
32. Kasar, S., Kumar, S., Saha, A., Tomar, B. S., Bajpai, R. K. Mechanistic and thermodynamic aspects of Cs(I) and Sr(II) interactions with smectite-rich natural clay. Environ. Earth Sci. 2017, 76, 1; https://doi.org/10.1007/s12665-017-6595-8.Search in Google Scholar
33. Missana, T., Garcia-Gutierrez, M., Benedicto, A., Ayora, C., De-Pourcq, K. Modelling of Cs sorption in natural mixed-clays and the effects of ion competition. Appl. Geochem. 2014b, 49, 95; https://doi.org/10.1016/j.apgeochem.2014.06.011.Search in Google Scholar
34. Montavon, G., Alhajji, E., Grambow, B. Study of the interaction of Ni2+ and Cs+ on MX−80 bentonite; effect of compaction using the “capillary method”. Environ. Sci. Technol. 2006, 40, 4672; https://doi.org/10.1021/es052483i.Search in Google Scholar PubMed
35. Siroux, B., Beaucaire, C., Tabarant, M., Benedetti, M. F., Reiller, P. E. Adsorption of strontium and cesium onto a Na−MX‒80 bentonite: experiments and building of a coherent thermodynamic modeling. Appl. Geochem. 2017, 87, 167; https://doi.org/10.1016/j.apgeochem.2017.10.022.Search in Google Scholar
36. Staunton, S., Roubaud, M. Adsorption of 137Cs on montmorillonite and illite; effect of charge compensating cation, ionic strength, concentration of Cs, K and fulvic acid. Clay Clay Miner. 1997, 45, 251; https://doi.org/10.1346/ccmn.1997.0450213.Search in Google Scholar
37. Sawhney, B. L. Selective sorption and fixation of cations by clay-minerals: review. Clay Clay Miner. 1972, 20, 93; https://doi.org/10.1346/ccmn.1972.0200208.Search in Google Scholar
38. Fuller, A. J., Shaw, S., Peacock, C. L., Trivedi, D., Small, J. S., Abrahamsen, L. G., Burke, I. T. Ionic strength and pH dependent multisite sorption of Cs onto a micaceous aquifer sediment. Appl. Geochem. 2014, 40, 32; https://doi.org/10.1016/j.apgeochem.2013.10.017.Search in Google Scholar
39. Semenkova, A. S., Evsiunina, M. V., Vermab, P. K., Mohapatra, P. K., Petrov, V. G., Seregina, I. F., Bolshov, M. A., Krupskaya, V. V., Romanchuk, A. Y., Kalmykov, S. N. Cs+ sorption onto Kutch clays: influence of competing ions. Appl. Clay Sci. 2018, 166, 88; https://doi.org/10.1016/j.clay.2018.09.010.Search in Google Scholar
40. Jaisi, D. P., Liu, C., Dong, H., Blake, R. E., Fein, J. B. Fe2+ sorption onto nontronite (NAu-2). Geochem. Cosmochim. Acta 2010, 72, 5361.10.1016/j.gca.2008.08.022Search in Google Scholar
41. Fukushi, K., Sakai, H., Ito, T., Tamura, A., Arai, S. Desorption of intrinsic cesium from smectite: inhibitive effects of clay particle organization on cesium desorption. Environ. Sci. Technol. 2014, 48, 10743; https://doi.org/10.1021/es502758s.Search in Google Scholar
42. Sasaki, T., Ueda, K., Saito, T., Aoyagi, N., Kobayashi, T., Takagi, I., Kimura, T., Tachi, Y. Sorption of Eu3+ on Na-montmorillonite studied by time-resolved laser fluorescence spectroscopy and surface complexation modeling. J. Nucl. Sci. Technol. 2016, 53, 592; https://doi.org/10.1080/00223131.2015.1066719.Search in Google Scholar
43. Bradbury, M. H., Baeyens, B. A generalized sorption model for the concentration dependent uptake of caesium by argillaceous rocks. J. Contam. Hydrol. 2000, 42, 141; https://doi.org/10.1016/s0169-7722(99)00094-7.Search in Google Scholar
44. Herbelin, A., Westall, J. FITEQL: A Computer Program for Determination of Chemical Equilibrium Constants from Experimental Data; Oregon State University: Corvallis, 1994.Search in Google Scholar
45. Bradbury, M. H., Baeyens, B. Sorption of Eu3+ on Na- and Ca-montmorillonites: experimental investigations and modeling with cation exchange and surface complexation. Geochem. Cosmochim. Acta 2002, 66, 2325; https://doi.org/10.1016/s0016-7037(02)00841-4.Search in Google Scholar
46. Missana, T., Garcia-Gutierrez, M., Alonso, U. Kinetics and irreversibility of cesium and uranium sorption onto bentonite colloids in a deep granitic environment. Appl. Clay Sci. 2004, 26, 137; https://doi.org/10.1016/j.clay.2003.09.008.Search in Google Scholar
47. Marcus, Y. A simple empirical model describing the thermodynamics of hydration of ions of widely varying charges, sizes, and shapes. Biophys. Chem. 1994, 51, 111; https://doi.org/10.1016/0301-4622(94)00051-4.Search in Google Scholar
48. Nightingale, E. R. Phenomenological theory of ion solvation. Effective radii of hydrated ions. J. Phys. Chem. 1959, 63, 1381; https://doi.org/10.1021/j150579a011.Search in Google Scholar
49. Zhong, C., Deng, Y., Hu, W., Qiao, J., Zhang, L., Zhang, J. A review of electrolyte materials and compositions for electrochemical super capacitors. Chem. Soc. Rev. 2015, 44, 7484; https://doi.org/10.1039/c5cs00303b.Search in Google Scholar
50. Palascak, M. W., Shields, G. C. Accurate experimental values for the free energies of hydration of H+, OH−, and H3O+. J. Phys. Chem. 2004, 108, 3692; https://doi.org/10.1021/jp049914o.Search in Google Scholar
51. Miyahara, K., Ashida, T., Kohara, Y., Yusa, Y., Sasaki, N. Effect of bulk density on diffusion for cesium in compacted sodium bentonite. Radiochim. Acta 1991, 293, 52–53.10.1524/ract.1991.5253.2.293Search in Google Scholar
52. Iijima, K., Tomura, T., Shoji, Y. Reversibility and modeling of adsorption behavior of cesium ions on colloidal montmorillonite particles. Appl. Clay Sci. 2010, 49, 262; https://doi.org/10.1016/j.clay.2010.05.016.Search in Google Scholar
53. Tachi, Y., Yotsuji, K. Diffusion and sorption of Cs+, Na+, I− and HTO in compacted sodium montmorillonite as a function of pore water salinity: integrated sorption and diffusion model. Geochem. Cosmochim. Acta 2014, 132, 75; https://doi.org/10.1016/j.gca.2014.02.004.Search in Google Scholar
54. Soltermann, D., Fernandes, M. M., Baeyens, B., Dahn, R., Miehe, J., Wehrli, B. B., Bradbury, M. H. Fe(II) sorption on a synthetic montmorillonite. A combined macroscopic and spectroscopic study. Environ. Sci. Technol. 1999, 47, 6978.10.1021/es304270cSearch in Google Scholar
55. Schwertmann, U. Solubility and dissolution of iron oxides. Plant Soil 1991, 130, 125; https://doi.org/10.1007/bf00011851.Search in Google Scholar
56. Knight, R. J., Sylva, R. N. Spectrophotometric investigation of iron(III) hydrolysis in light and heavy water at 25 °C. J. Inorg. Nucl. Chem. 1975, 37, 779; https://doi.org/10.1016/0022-1902(75)80539-2.Search in Google Scholar
57. Krishnamurti, G. S. R., Violante, A., Huang, P. M. Influence of montmorillonite on Fe(II) oxidation products. Clay Miner. 1998, 33, 205; https://doi.org/10.1180/000985598545561.Search in Google Scholar
58. Helm, L., Merbach, A. E. Water exchange on metal ions: experiments and simulations. Coord. Chem. Rev. 1999, 187, 151; https://doi.org/10.1016/s0010-8545(99)90232-1.Search in Google Scholar
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