Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-29T15:59:15.641Z Has data issue: false hasContentIssue false

About U(t) form of pH-dependence of glass corrosion rates at zero surface to volume ratio

Published online by Cambridge University Press:  08 April 2015

Michael I. Ojovan
Affiliation:
Department of Nuclear Energy, IAEA, Vienna 1020, Austria.
William E. Lee
Affiliation:
Centre for Nuclear Engineering, Imperial College London, London SW7 2AZ, UK
Get access

Abstract

The pH-dependence of glass corrosion rates has a well-known U-shaped form with minima for near-neutral solutions. This paper analyses the change of U-shaped form with time and reveals that the pH dependence evolves even for solutions that have pH not affected by glass corrosion mathematically corresponding to a zero surface to volume ratio. The U(t) dependence is due to changes of concentration profiles of elements in the near-surface layers of glasses in contact with water and is most evident within the initial stages of glass corrosion at relatively low temperatures. Numerical examples are given for the nuclear waste borosilicate glass K-26 which is experimentally characterised by an effective diffusion coefficient of caesium DCs = 4.5 10-12 cm2/day and by a rate of glass hydrolysis in non-saturated groundwater as high as rh = 100 nm/year The changes of U-shaped form need to be accounted when assessing the performance of glasses in contact with water solutions.

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

Jantzen, C.M., Lee, W.E., Ojovan, M.I.. Radioactive Waste Conditioning, Immobilisation, and Encapsulation Processes and Technologies: Overview and Advances. Chapter 6 in: Lee, W.E., Ojovan, M.I., Jantzen, C.M.. Radioactive waste management and contaminated site clean-up: Processes, technologies and international experience. p. 171272, Woodhead, Cambridge (2013).CrossRefGoogle Scholar
Gin, S., Abdelouas, A., Criscenti, L.J., Ebert, W.L., Ferrand, K., Geisler, T., Harrison, M.T., Inagaki, Y., Mitsui, S., Mueller, K.T., Marra, J.C., Pantano, C.G., Pierce, E.M., Ryan, J.V., Shoefield, J.M., Steefel, C.I., Vienna, J.D.. An international initiative on long-term behaviour of high-level nuclear waste glass. Materials Today, 16 (6) 243248 (2013).CrossRefGoogle Scholar
Chroneos, A., Rushton, M.J.D., Jiang, C., Toukalas, L.H.. Nuclear wasteform materials: Atomistic simulation case studies. J. Nucl. Mater., 443, 2939 (2013).CrossRefGoogle Scholar
Wicks, G.. Nuclear waste vitrification – The geology connection. J. Non-Crystalline Solids, 84 241250 (1984).CrossRefGoogle Scholar
Statistical Calculation and Development of Glass Properties. http://glassproperties.com/ (accessed on 21.05.2014).Google Scholar
Bacon, D., Pierce, E.. Development of long-term behaviour models for radioactive waste forms. Chapter 14 in: Ojovan, M.I.. Handbook of advanced radioactive waste conditioning technologies. ISBN 1 84569 626 3. Woodhead, Cambridge, p.433454 (2011).CrossRefGoogle Scholar
Bacon, D.H., McGrail, B.P.. Waste form release calculations for performance assessment of the Hanford immobilized low-activity waste disposal facility using a parallel, coupled unsaturated flow and reactive transport simulator. Mat. Res. Soc. Symp. Proc. 757, II1.9.1-6 (2003).Google Scholar
Ojovan, M.I., Hand, R.J., Ojovan, N.V., Lee, W.E.. Corrosion of alkali-borosilicate waste glass K-26 in non-saturated conditions. J. Nucl. Mater. 340, 1224 (2005).CrossRefGoogle Scholar
Ojovan, M.I., Pankov, A.S., Lee, W.E.. The ion exchange phase in corrosion of nuclear waste glasses. J. Nucl. Mater., 358, 5768 (2006).CrossRefGoogle Scholar
Bacon, D.H., Ojovan, M.I., McGrail, B.P., Ojovan, N.V., Startceva, I.V.. Vitrified waste corrosion rates from field experiment and reactive transport modelling. Proc. ICEM ‘03: The 9th International Conference on Radioactive Waste Management and Environmental Remediation, September 21 – 25, 2003, Examination School, Oxford, England, 7p., CD ROM 4509.pdf. (2003).Google Scholar
Ojovan, M.I., Lee, W.E.. An Introduction to Nuclear Waste Immobilisation, Second Edition, Elsevier, 2nd Edition, Amsterdam, 362 p. (2014).CrossRefGoogle Scholar
Strachan, D.M.. Glass dissolution: testing and modeling for long-term behavior J. Nucl. Mater., 298, 6977 (2001).CrossRefGoogle Scholar
Ebert, W.L.. The effect of the leachate pH and the ratio of glass surface area to leachant volume on glass reactions. Phys. Chem. Glasses, 34 (2) 5865 (1993).Google Scholar
Ojovan, M.I., Lee, W.E., Barinov, A.S., Startceva, I.V., Bacon, D.H., McGrail, B.P., Vienna, J.D.. Corrosion of low level vitrified radioactive waste in a loamy soil. Glass Technol., 47 (2), 4855 (2006).Google Scholar
Grambow, B.. A general rate equation for nuclear waste corrosion. Mat. Res. Soc. Symp. Proc. 44, 1527 (1985).CrossRefGoogle Scholar
Belyustin, A.A., Shultz, M.M.. Interdiffusion of cations and concomitant processes in near surface layers of alkali-silicate glasses treated by water solutions. Physics and Chemistry of Glass, 9, 327 (1983).Google Scholar
Boksay, Z., Bouquet, G., Dobos, S., The kinetics of the formation of leached layers on glass surfaces, Phys. Chem. Glasses, 9, 6971 (1968).Google Scholar
Melling, P., Allnatt, A.. Modelling of leaching and corrosion of glass, J. Non-Cryst. Solids, 42, 553560 (1980).CrossRefGoogle Scholar