Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-20T03:37:59.353Z Has data issue: false hasContentIssue false

Surface Decontamination by Photocatalysis

Published online by Cambridge University Press:  07 February 2012

Richard J. Wilbraham
Affiliation:
Engineering Department, Lancaster University, Lancashire, LA1 4YW, UK
Colin Boxall
Affiliation:
Engineering Department, Lancaster University, Lancashire, LA1 4YW, UK
Robin J. Taylor
Affiliation:
National Nuclear Laboratory, B170 Central Laboratory, Seascale, Cumbria CA20 1PG, UK
Get access

Abstract

Currently in the nuclear industry, surface contamination in the form of radioactive metal or metal oxide deposits is most commonly removed by chemical decontamination, electrochemical decontamination or physical attrition. Physical attrition techniques are generally used on structural materials (concrete, plaster), with (electro)chemical methods being used to decontaminate metallic or painted surfaces. The most common types of (electro)chemical decontamination are the use of simple mineral acids such as nitric acid or cerium (IV) oxidation (MEDOC). Use of both of these reagents frequently results in the dissolution of a layer of the substrate surface increasing the amount of secondary waste which leads to greater burden on downstream effluent treatment and waste management plants. In this context, both mineral acids and MEDOC can be indiscriminate in the surfaces attacked during deployment, e.g. attacking in transit through a pipe system to the site of contamination resulting in both diminished effect of the decontaminating reagent upon arrival at its target site and an increased secondary waste management requirement. This provides two main requirements for a more ideal decontamination reagent: Improved area specificity and a dissolution power equal to or greater than the previously mentioned current decontaminants.

Photochemically promoted processes may provide such a decontamination technique. Photochemical reduction of metal ion valence states to aid in heavy metal deposition has already been extensively studied, with reductive manipulation also being achieved with uranium and plutonium simulants (Ce). Importantly photooxidation of a variety of solution phase metals, including neptunium, has also been achieved. Here we briefly review existing decontamination techniques and report on the potential application of photo promoted oxidation technologies to metal dissolution (including process steels) and to the dissolution of adsorbed actinide contaminants.

Type
Research Article
Copyright
Copyright © Materials Research Society 2012

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

1. International Atomic Energy Agency, State of the Art Technology for Decontamination and Dismantling of Nuclear Facilities: Technical Report Series no. 395, (International Atomic Energy Agency, 1999), pp 3233.Google Scholar
2. Caire, J.P., Laurent, F., Cullie, S., Dalard, F., Fulconis, J.M., Delagrange, H., J. Appl. Electrochem. 33, 703 (2003).Google Scholar
3. Suwa, T., Kuribayashi, N., Tachikawa, E., J. Nucl. Sci. Technol. 23, 622 (1986); 25, 574(1988).Google Scholar
4. Matheswaran, M., Balaji, S., Chung, S.J., Moon, I.S., Catal. Commun. 8, 1497 (2007).Google Scholar
5. Bradbury, D., in Water Chemistry of Nuclear Reactor Systems 8, (British Nuclear Energy Society, Thomas Telford Ltd, 2000), pp 173178.Google Scholar
6. Wille, H., in Water Chemistry of Nuclear Reactor Systems 8, (British Nuclear Energy Society, Thomas Telford Ltd, 2000), pp 179184.Google Scholar
7. Inami, , Sato, Y., Kanasaki, T., Suzuki, N., Fujimori, A., Makihara, A., Wille, H., Strohmer, F., in Water Chemistry of Nuclear Reactor Systems 8, (British Nuclear Energy Society, Thomas Telford Ltd, 2000), pp 444450.Google Scholar
8. Wille, H., Bertholdt, H.O., Nucl. Eur. 8, 41 (1988).Google Scholar
9. Wille, H., Bertholdt, H.O., in Water Chemistry of Nuclear Reactor Systems 7, (British Nuclear Energy Society, Thomas Telford Ltd, 1996), pp 317323.Google Scholar
10. Shimizu, R., Sawada, K., Enokida, Y., Yamamoto, I., J. Nucl. Sci. Technol. 43, 694 (2006).Google Scholar
11. Hoffman, A.J., Carraway, E.R., Hoffmann, M.R., Environ Sci Technol, 28, 776 (1994).Google Scholar
12. Goto, H., Hanada, Y., Ohno, T., Matsumura, M., J. Catal. 225, 223 (2004).Google Scholar
13. Bandara, J., Guasaquillo, I., Bowen, P., Soare, L., Jardim, W.F., Kiwi, J., Langmuir 21, 8554 (2005).Google Scholar
14. Premkumar, J., Ramaraj, R., J. Mol. Catal. A-Chem. 142, 153 (1999).Google Scholar
15. Maya, L., Gonzalez, B.D., Lance, M.J., Holcomb, D.E., J. Radioanal. Nucl. Chem. 261, 605 (2004).Google Scholar
16. dos Santos, L.R., Sbampato, M.E., dos Santos, A.M., J. Radioanal. Nucl. Chem. 261, 203 (2004).Google Scholar
17. Amme, M., Radiochim. Acta. 90, 399 (2002).Google Scholar
18. Corbel, C., Sattonnay, G., Guilbert, S., Garrido, F., Barthe, M.F., Jegou, C., J. Nucl. Mater. 348, 1 (2006).Google Scholar
19. Amme, M., Renker, B., Schmid, B., Feth, M.P., Bertagnolli, H., Döbelin, W., J. Nucl. Mater. 306, 202 (2002).Google Scholar
20. Clarens, F., De Pablo, J., Diez-Perez, I., Casas, I., Gimenez, J., Rovira, M., Environ Sci Technol, 38, 6656 (2004).Google Scholar
21. Itagaki, M., Nakazawa, H., Watanabe, K., Noda, K., Corros. Sci. 39, 901 (1997).Google Scholar