Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-26T17:49:29.182Z Has data issue: false hasContentIssue false
  • English
  • Français

Redox interactions of technetium with iron-bearing minerals

Published online by Cambridge University Press:  05 July 2018

J. M. McBeth ,
J. R. Lloyd ,
G. T. W. Law ,
F. R. Livens ,
I. T. Burke  and
K. Morris
J. M. McBeth*
Affiliation:
Research Centre for Radwaste and Decommissioning and Williamson Research Centre for Molecular Environmental Science, School of Earth, Atmospheric and Environmental Sciences, The University of Manchester, Manchester M13 9PL, UK
J. R. Lloyd
Affiliation:
Research Centre for Radwaste and Decommissioning and Williamson Research Centre for Molecular Environmental Science, School of Earth, Atmospheric and Environmental Sciences, The University of Manchester, Manchester M13 9PL, UK
G. T. W. Law
Affiliation:
Research Centre for Radwaste and Decommissioning and Williamson Research Centre for Molecular Environmental Science, School of Earth, Atmospheric and Environmental Sciences, The University of Manchester, Manchester M13 9PL, UK
F. R. Livens
Affiliation:
Research Centre for Radwaste and Decommissioning and Williamson Research Centre for Molecular Environmental Science, School of Earth, Atmospheric and Environmental Sciences, The University of Manchester, Manchester M13 9PL, UK Centre for Radiochemistry Research, The University of Manchester, Manchester M13 9PL, UK
I. T. Burke
Affiliation:
Earth System Science Institute, School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK
K. Morris*
Affiliation:
Research Centre for Radwaste and Decommissioning and Williamson Research Centre for Molecular Environmental Science, School of Earth, Atmospheric and Environmental Sciences, The University of Manchester, Manchester M13 9PL, UK
*
† current address: Bigelow Laboratory for Ocean Sciences, 180 McKown Point Road, West Boothbay Harbor, Maine, 04575, USA
*E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

Iron minerals influence the environmental redox behaviour and mobility of metals including the long-lived radionuclide technetium. Technetium is highly mobile in its oxidized form pertechnetate (Tc(VII)O4–), however, when it is reduced to Tc(IV) it immobilizes readily via precipitation or sorption. In low concentration tracer experiments, and in higher concentration XAS experiments, pertechnetate was added to samples of biogenic and abiotically synthesized Fe(II)-bearing minerals (bio-magnetite, bio-vivianite, bio-siderite and an abiotically precipitated Fe(II) gel). Each mineral scavenged different quantities of Tc(VII) from solution with essentially complete removal in Fe(II)-gel and bio-magnetite systems and with 84±4% removal onto bio-siderite and 68±5% removal onto bio-vivianite over 45 days. In select, higher concentration, Tc XAS experiments, XANES spectra showed reductive precipitation to Tc(IV) in all samples. Furthermore, EXAFS spectra for bio-siderite, bio-vivianite and Fe(II)-gel showed that Tc(IV) was present as short range ordered hydrous Tc(IV)O2-like phases in the minerals and for some systems suggested possible incorporation in an octahedral coordination environment. Low concentration reoxidation experiments with air-, and in the case of the Fe(II) gel, nitrate-oxidation of the Tc(IV)-labelled samples resulted in only partial remobilization of Tc. Upon exposure to air, the Tc bound to the Fe-minerals was resistant to oxidative remobilization with a maximum of ∼15% Tc remobilized in the bio-vivianite system after 45 days of air exposure. Nitrate mediated oxidation of Fe(II)-gel inoculated with a stable consortium of nitrate-reducing, Fe(II)-oxidizing bacteria showed only 3.8±0.4% remobilization of reduced Tc(IV), again highlighting the recalcitrance of Tc(IV) to oxidative remobilization in Fe-bearing systems. The resultant XANES spectra of the reoxidized minerals showed Tc(IV)-like spectra in the reoxidized Fe-phases. Overall, this study highlights the role that Fe-bearing biogenic mineral phases have in controlling reductive scavenging of Tc(VII) to hydrous TcO2-like phases onto a range of Fe(II)-bearing minerals. In addition, it suggests that on reoxidation of these phases, Fe-bound Tc(IV) may be octahedrally coordinated and is largely recalcitrant to reoxidation over medium-term timescales. This has implications when considering remediation approaches and in predictions of the long-term fate of Tc in the nuclear legacy.

Keywords

technetiumredox cyclingiron mineralsremediation
Type
Research Article
Information
Mineralogical Magazine , Volume 75 , Issue 4 , August 2011 , pp. 2419 - 2430
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2011

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

Adams, L.K. (2004) Iron reduction in sediments associated with shell beds: refining models of bacterial Fe(ITI)-reduction in marginal marine sedimentary systems. Ph.D. thesis, The University of Manchester, UK.Google Scholar
Alliot, I., Alliot, C., Vitorge, P. and Fattahi, M. (2009) Speciation of Tc(IV) in bicarbonate media. Environmental Science & Technology, 43, 9174–9182.CrossRefGoogle Scholar
Begg, J.D.C., Burke, I.T. and Morris, K. (2007) The behaviour of technetium during microbial reduction in amended soils from Dounreay, UK. Science of the Total Environment, 373, 297–304.CrossRefGoogle ScholarPubMed
Begg, J.D.C., Burke, I.T., Charnock, J.M., Morris, K. (2008) Technetium reduction and reoxidation behaviour in Dounreay soils. Radiochimica Ada, 96, 631–636.Google Scholar
Binsted, N. (1998) CCLRC Daresbury Laboratory EXCURV98 program. CCLRC Daresbury Laboratory, Warrington, UK.Google Scholar
Burke, I.T., Boothman, C., Lloyd, J.R., Mortimer, R.J.G., Livens, F.R. and Morris, K. (2005) Effects of progressive anoxia on the solubility of technetium in sediments. Environmental Science & Technology, 39, 4109–4116.CrossRefGoogle ScholarPubMed
Burke, I.T., Boothman, C, Lloyd, J.R., Livens, F.R., Charnock, J.M., McBeth, J.M., Mortimer, R.J.G. and Morris, K. (2006) Reoxidation behavior of technetium, iron, and sulfür in estuarine sediments. Environmental Science & Technology, 40, 3529–3535.CrossRefGoogle ScholarPubMed
Burke, I.T., Livens, F.R., Lloyd, J.R., Brown, A.P., Law, G.T.W., McBeth, J.M., Ellis, B.L., Lawson, R.S. and Morris, K. (2010) The fate of technetium in reduced estuarine sediments: combining direct and indirect analyses. Applied Geochemistry, 25, 233—241.CrossRefGoogle Scholar
Fredrickson, J.K., Zachara, J.M., Kennedy, D.W., Kukkadapu, R.K, McKinley, J.P., Heald, S.M., Liu, C. and Plymale, A.E. (2004) Reduction of TCO4 by sediment-associated biogenic Fe(II). Geochimica et Cosmochimica Acta, 68, 3171—3187.CrossRefGoogle Scholar
Fredrickson, J.K., Zachara, J.M., Plymale, A.E., Heald, S.M., McKinley, J.P., Kennedy, D.W., Liu, C. and Nachimuthu, P. (2009) Oxidative dissolution potential of biogenic and abiogenic TcO2 in subsurface sediments. Geochimica et Cosmochimica Acta, 73, 2299–2313.CrossRefGoogle Scholar
Geissler, A., Law, G.T.W., Boothman, C, Morris, K., Burke, I.T., Livens, F.R. and Lloyd, J.R. (2011) Microbial communities associated with the oxidation of iron and teehnetium in bioreduced sediments. Geomicrobiology Journal, 28, 507—518.CrossRefGoogle Scholar
Gu, B., Dong, W., Liang, L. and Wall, N.A. (2011) Dissolution of Tc(IV) oxide by natural and synthetic organic ligands under both reducing and oxidizing conditions. Environmental Science & Technology, 45, 4771–4777.CrossRefGoogle ScholarPubMed
Gurman, S.J., Binsted, N. and Ross, I. (1984) A rapid, exact curved-wave theory for EXAFS calculations. Journal of Physics C: Solid State Physics, 17, 143–151.CrossRefGoogle Scholar
Islam, F.S., Pederick, R.L., Gault, A.G., Adams, L.K., Polya, D.A., Charnock, J.M. and Lloyd, J.R. (2005) Interactions between the Fe(III)-reducing bacterium Geobacter sulfürreducens and arsenate, and capture of the metalloid by biogenic Fe(II). Applied and Environmental Microbiology, 71, 8642—8648.CrossRefGoogle Scholar
Istok, J.D., Senko, J.M., Krumholz, L.R., Watson, D., Bogle, M.A., Peacock, A., Chang, Y.J. and White, D.C. (2004) In situ bioreduction of teehnetium and uranium in a nitrate- contaminated aquifer. Environmental Science & Technology, 38, 468—475.CrossRefGoogle Scholar
Jaisi, D.P., Dong, H., Plymale, A.E., Frederickson, J.K., Zachara, J.M., Heald, S.E. and Liu, C. (2009) Reduction and long-term immobilization of teehne-tium by Fe(II) associated with clay mineral nontronite. Chemical Geology, 264, 127—138.CrossRefGoogle Scholar
Keith-Roach, M.J., Morris, K. and Dahlgaard, H. (2003) An investigation into teehnetium binding in sediments. Marine Chemistry, 81, 149—162.CrossRefGoogle Scholar
Law, G.T.W., Geissler, A., Boothman, C., Burke, I.T., Livens, F.R., Lloyd, J.R. and Morris, K. (2010a) Role of nitrate in conditioning aquifer sediments for teehnetium bioreduction. Environmental Science & Technology, 44, 150–155.CrossRefGoogle Scholar
Law, G.T.W., Geissler, A., Lloyd, J.R., Livens, F.R. Boothman, Begg, J.D.C., Deneke, M.A., Rothe, J., Dardenne, K, Burke, I.T., Charnock, J.M. and Morris, K. (2010b) Geomicrobial redox cycling of the transuranic element neptunium. Environmental Science & Technology, 44, 8924–8929.CrossRefGoogle Scholar
Law, G.T.W., Geissler, A., Burke, I.T., Livens, F.R., Lloyd, J.R., McBeth, J.M. and Morris, K. (2011) Uranium redox cycling in sediment and biomineral systems. Geomicrobiology Journal, 28, 497—506.CrossRefGoogle Scholar
Lear, G., McBeth, J.M., Boothman, C., Gunning, D.J., Ellis, B.L., Lawson, R.S., Morris, K., Burke, I.T., Bryan, N.D., Brown, A.P., Livens, F.R. and Lloyd, J.R. (2010) Probing the biogeochemical behaviour of teehnetium using a novel nuclear imaging approach. Environmental Science & Technology, 44, 156—162.CrossRefGoogle ScholarPubMed
Li, X. and Krumholz, L.R. (2008) Influence of nitrate on microbial reduction of pertechnetate. Environmental Science and Technology, 42, 1910–1915.CrossRefGoogle ScholarPubMed
Lloyd, J.R., Sole, V.A., van Praagh, C.V.G. and Lovley, D.R. (2000) Direct and Fe(II)-mediated reduction of teehnetium by Fe(III)-reducing bacteria. Applied and Environmental Microbiology, 66, 3743—3749.CrossRefGoogle ScholarPubMed
Lovley, D.R. and Phillips, E.J.P. (1986) Organic matter mineralization with reduction of ferric iron in anaerobic sediments. Applied and Environmental Microbiology, 51, 683–689.CrossRefGoogle ScholarPubMed
Lovley, D.R., Stolz, J.F., Nord, G.L. and Phillips, E.J.P. (1987) Anaerobic production of magnetite by a dissimilatory iron-reducing microorganism. Nature, 330, 252–254.CrossRefGoogle Scholar
Lukens, W.W., Jr., Bucher, J.J., Edelstein, N.M. and Shuh, D.K. (2002) Products of pertechnetate radiolysis in highly alkaline solution: structure of TcO2·xH2O. Environmental Science & Technology, 36, 1124–1129.CrossRefGoogle Scholar
Maes, A., Geraedts, K., Bruggeman, C., Vancluysen, J., Rossberg, A. and Hennig, C. (2004) Evidence for the interaction of Tc colloids with humic substances by X-ray absorption spectroscopy. Environmental Science & Technology, 38, 2044–2051.CrossRefGoogle ScholarPubMed
Meyer, R., Arnold, W.D., Case, F. and O'Kelley, G.D. (1991) Solubilities of Tc(IV) oxides. Radiochimica Acta, 55, 11–18.CrossRefGoogle Scholar
McBeth, J.M., Lear, G., Morris, K., Burke, I.T., Livens, F.R. and Lloyd, J.R. (2007) Teehnetium reduction and reoxidation in aquifer sediments. Geomicrobiology Journal, 24, 189—197.CrossRefGoogle Scholar
Michalsen, M.M., Goodman, B.A., Kelly, S.D., Kemner, K.M., McKinley, J.P., Stucki, J.W. and Istok, J.D. (2006) Uranium and teehnetium bio-immobilization in intermediate-scale physical models of an in situ bio-barrier. Environmental Science & Technology, 40, 7048–7053.CrossRefGoogle Scholar
Morris, K., Butterworth, J.C. and Livens, F.R. (2000) Evidence for the remobilization of Sellafield waste radionuclides in an intertidal salt marsh, west Cumbria, U.K. Estuarine, Coastal and Shelf Science, 51, 613–625.CrossRefGoogle Scholar
Morris, K., Livens, F.R., Charnock, J.M., Burke, I.T., McBeth, J.M., Begg, J.D.C., Boothman, C. and Lloyd, J.R. (2008) An X-ray absorption study of the fate of teehnetium in reduced and reoxidised sediments and mineral phases. Applied Geochemistry, 23, 603—617.CrossRefGoogle Scholar
Plymale, A.E., Fredrickson, J.K., Zachara, J.M., Dohnalkova, A.C., Heald, S.M., Moore, D.A., Kennedy, D.W., Marshall, M.A., Wang, C., Resch, C.T. and Nachimuthu, P. (2011) Competitive reduction of pertechnetate by dissimilatory metal reducing bacteria and biogenic Fe(II). Environmental Science & Technology, 45, 951–957.CrossRefGoogle Scholar
Senko, J.M., Mohamed, Y., Dewers, T.A. and Krumholz, L.R. (2005) Role for Fe(III) minerals in nitrate-dependent microbial U(VI) oxidation. Environmental Science and Technology, 39, 2529–2536.CrossRefGoogle ScholarPubMed
Skomurski, F.N., Rosso, K.M., Krupka, K.M. and McGrail, B.P. (2010) Technetium incorporation into hematite (a-Fe2O3). Environmental Science and Technology, 44, 5855–5861.CrossRefGoogle Scholar
Standring, W.J.F., Oughton, D.H. and Salbu, B. (2002) Potential remobilisation of Cs-137, Co-60, Tc-99 and Sr-90 from contaminated Mayak sediments in river and estuary environments. Environmental Science and Technology, 36, 2330–2337.CrossRefGoogle Scholar
Wildung, R.E., Li, S.W., Murray, C.J., Krupka, K.M., Xie, Y., Hess, N.J. and Roden, E.E. (2004) Technetium reduction in sediments of a shallow aquifer exhibiting dissimilatory iron reduction potential. FEMS Microbiology Ecology, 49, 151–162.CrossRefGoogle ScholarPubMed
Wu, W-M., Carley, J., Luo, J., Ginder-Vogel, M.A., Cardenas, E., Leigh, M.B., Hwang, C., Kelly, S.D., Ruan, C., Wu, L., van Nostrand, J., Gentry, T., Lowe, K., Mehlhorn, T., Carroll, S., Luo, W., Fields, M.W., Gu, B., Watson, D., Kemner, K.M., Marsh, T., Tiedje, I., Zhou, J., Fendorf, S., Kitanidis, P.K, Jardine, P.M. and Criddle, C.S. (2007) In situ bioreduction of uranium (VI) to submicromolar levels and reoxidation by dissolved oxygen. Environmental Science and Technology, 41, 5716–5723.CrossRefGoogle ScholarPubMed
Wu, W-M., Carley, I., Green, S.J., Luo, I, Kelly, S.D., van Nostrand, J., Lowe, K., Mehlhorn, T., Carroll, S., Boonchayanant, B., Lofller, F.E., Watson, D., Kemner, K.M., Zhou, I, Kitanidis, P.K, Kostka, J.E., Jardine, P.M. and Criddle, C.S. (2010). Effects of nitrate on the stability of uranium in a bioreduced region of the subsurface. Environmental Science and Technology, 44, 5104–5111.CrossRefGoogle Scholar
Zachara, R.T., Heald, S.M., Jeon, B-H., Kukkadapu, R.A., Liu, C., McKinley, J.P., Dohnalkova, A.C. and Moore, D.A. (2007). Reduction of pertechnetate [Tc(VII)] by aqueous Fe(II) and the nature of the solid phase redox products. Geochimica et Cosmochimica Acta, 71, 2137–2157.CrossRefGoogle Scholar