Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-05T04:22:03.907Z Has data issue: false hasContentIssue false
  • English
  • Français

Partitioning of Fe(II) in reduced nontronite (NAu-2) to reactive sites: Reactivity in terms of Tc(VII) reduction

Published online by Cambridge University Press:  01 January 2024

Deb P. Jaisi ,
Hailiang Dong  and
John P. Morton
Deb P. Jaisi
Affiliation:
Department of Geology, Miami University, Oxford, OH 45056, USA Department of Geology and Geophysics, Yale University, PO Box 20820, New Haven, CT 06520, USA
Hailiang Dong*
Affiliation:
Department of Geology, Miami University, Oxford, OH 45056, USA
John P. Morton
Affiliation:
Department of Geology, Miami University, Oxford, OH 45056, USA
*
* E-mail address of corresponding author: [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Clay minerals impart important chemical properties to soils, in part, by virtue of changes in the redox state of Fe in their crystal structures. Therefore, measurement of Fe(III)/Fe(II) and partitioning of Fe(II) in different reactive sites in clay minerals (during biological and chemical Fe(III) reduction) is essential to understand their role and their relative reactivity in terms of reduction and immobilization of heavy metal contaminants such as technetium. This study had three objectives: (1) to understand the degree of dissolution of nontronite (Fe-rich smectite) as a result of chemical and biological reduction of Fe(III) in the structure; (2) to quantify partitioning of chemically and biologically produced Fe(II) into different reactive sites in reduced nontronite, including aqueous Fe2+, ammonium chloride-extractable Fe(II) (mainly from the ion-exchangeable sites, denoted as Fe(II)NH4Cl${\rm{Fe}}{\left( {{\rm{II}}} \right)_{{\rm{N}}{{\rm{H}}_4}{\rm{Cl}}}}$), sodium acetate-extractable Fe(II) (mainly from the surface complexation sites, denoted as Fe(II)acetate), and structural Fe(II) (denoted as Fe(II)str); and (3) to evaluate the reactivity of these Fe(II) species in terms of Tc(VII) reduction. Chemical and biological reduction of Fe(III) in nontronite (NAu-2) was performed, and reduced nontronite samples with different extents of Fe(III) reduction (1.2–71%) were prepared. The extent of reductive dissolution was measured as a function of the extent of Fe(III) reduction. Our results demonstrated that chemically and biologically produced Fe(II) in NAu-2 may be accommodated in the NAu-2 structure if the extent of Fe(III) reduction is small (< ∼30%). When the extent of reduction was >∼30%, dissolution of nontronite occurred with a corresponding decrease in crystallinity of residual nontronite. The Fe(II) produced was available for partitioning into four species: Fe(ab)2+${\rm{Fe}}_{\left( {{\rm{ab}}} \right)}^{2 + }$, Fe(II)acetate, Fe(II)NH4Cl${\rm{Fe}}{\left( {{\rm{II}}} \right)_{{\rm{N}}{{\rm{H}}_4}{\rm{Cl}}}}$, and Fe(II)str. The increase in Fe(II)acetate during the early stages of Fe(III) reduction indicated that the Fe(II) released had the greatest affinity for the surface-complexation sites, but this site had a limited capacity (∼60 µmol of Fe(II)/g of NAu-2). The subsequent increase in Fe(II)NH4Cl${\rm{Fe}}{\left( {{\rm{II}}} \right)_{{\rm{N}}{{\rm{H}}_4}{\rm{Cl}}}}$ indicated that the released Fe(II) partitioned into the exchangeable sites once the amount of Fe at the surface-complexation sites reached half of its maximum site capacity. The fraction of Fe(II)str decreased concomitantly, as a result of Fe(II) release from the NAu-2 structure, from 100% when the extent of Fe(III) reduction was <30% to nearly 65% when the extent of Fe(III) reduction reached 71%. The Fe(II)acetate and Fe(II)str exhibited greater reactivity in terms of Tc(VII) reduction than the Fe(II)NH4Cl${\rm{Fe}}{\left( {{\rm{II}}} \right)_{{\rm{N}}{{\rm{H}}_4}{\rm{Cl}}}}$. Clearly, the surface-complexed and structural Fe(II) are the desirable species when reduced clay minerals are used to reduce and immobilize soluble heavy metals in contaminated groundwater and soils. These results have important implications for understanding microbe—clay mineral interactions and heavy metal immobilization in clay-rich natural environments.

Keywords

Fe(III) ReductionFe(II) partitioningShewanella putrefaciens CN32NAu-2Tc(VII) Reduction
Type
Research Article
Information
Clays and Clay Minerals , Volume 56 , Issue 2 , April 2008 , pp. 175 - 189
Copyright
Copyright © 2008, The Clay Minerals Society

References

Albinsson, Y. Cristiansen-satmark, B. Engkvist, I. and Johansson, W., 1991 Transport of actinides and Tc through a bentonite backfilling containing small quantities of iron or copper Radiochimica Acta 52/53 283–286.CrossRefGoogle Scholar
Amonette, J.E. and Fitch, A., 2003 Iron redox chemistry of clays and oxides: environmental applications Electrochemical Properties of Clays Aurora, Colorado, USA The Clay Minerals Society 89–148.Google Scholar
Ammonette, J.E. Scott, A.D. and Churchman, G.J., 1995 Oxidative weathering of trioctahedral micas by buffered H2O2 solutions Clays Controlling the Environment Melbourne CSIRO Publishing 355–361.Google Scholar
Amran, K. and Ganor, J., 2005 The combined effect of pH and temperature on smectite dissolution rate under acidic conditions Geochimica et Cosmochimica Acta 69 2535–2546.CrossRefGoogle Scholar
Andrade, S. Hypolito, R. Ulbrich, H.H. and Silva, M.L., 2002 Iron(II) oxide determination in rocks and minerals Chemical Geology 182 85–89.CrossRefGoogle Scholar
Baeyens, B. and Bradbury, M.H., 1997 A mechanistic description of Ni and Zn sorption on Na-montmorillonite. Part I: Titration and sorption measurements Journal of Contaminant Hydrology 27 199–222.CrossRefGoogle Scholar
Bradbury, M.H. and Baeyens, B., 2002 Sorption of Eu on Na-and Ca-montmorillonites: Experimental investigations and modeling with cation exchange and surface Geochimica et Cosmochimica Acta 66 2325–2334.CrossRefGoogle Scholar
Bratu, C. Bratu, G. Galateanu, I. and Roman, M., 1975 Study of lower valence states of technetium Journal of Radioanalytical Chemistry 26 5–16.CrossRefGoogle Scholar
Brusic, V. and Diggle, J.W., 1972 Passivation and passivity The Anodic Behavior of Metals and Semiconductors Series New York Marcel and Dekker, Inc. 1–80.Google Scholar
Buerge, I.J. and Hug, S.J., 1999 Influence of mineral surfaces on chromium(VI) reduction by iron(II) Environmental Science and Technology 33 4285–4291.CrossRefGoogle Scholar
Bukka, K. Miller, J.D. and Shabtai, J., 1992 FTIR study of deuterated montmorillonites: Structural features relevant to pillared clay stability Clays and Clay Minerals 40 92–102.CrossRefGoogle 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 and Technology 39 4109–4116.CrossRefGoogle ScholarPubMed
Cantrell, K.J. Serne, R.J. and Last, G.V., 2003 Hanford Contaminant Distribution Coefficient Database and Users Guide Richland, Washington Pacific Northwest National Laboratory.CrossRefGoogle Scholar
Cardile, C.M. and Slade, P.G., 1987 Structural study of a benzidine-vermiculite intercalate having a high tetrahedral-iron content by 57Fe Mössbauer spectroscopy Clays and Clay Minerals 35 203–207.CrossRefGoogle Scholar
Cataldo, D.A. Garland, T.R. Wildung, R.E. and Fellows, R.J., 1989 Comparative metabolic behaviour and interrelationships of Tc and S in soyabean plants Health Physics 57 281–288.CrossRefGoogle ScholarPubMed
Cervini-Silva, J., 2004 Coupled charge transfer- and hydrophilic-interactions between polychlorinated methanes, ethanes, and ethenes and redox-manipulated smectite clay minerals Langmuir 20 9878–9881.CrossRefGoogle ScholarPubMed
Cervini-Silva, J. Larson, R.A. and Stucki, J.W., 2006 Hydration/expansion and cation charge compensation modulate the Bronsted basicity of distorted clay water Langmuir 22 2145–2151.CrossRefGoogle ScholarPubMed
Charlet, L. Silvester, E. and Liger, E., 1998 N-compound reduction and actinide immobilization in surficial fluids by Fe(II): The surface =FeIIIOFeIIOHo species, as major reductant Chemical Geology 151 85–93.CrossRefGoogle Scholar
Chisholm-Brause, C. Conradason, S.D. Buscher, C.T. Eller, P.G. and Morris, D.E., 1994 Speciation of uranyl sorbed at multiple binding sites on montmorillonite Geochimica et Cosmochimica Acta 58 3625–3631.CrossRefGoogle Scholar
Cooper, D.C. Picardal, F. Rivera, J. and Talbot, C., 2000 Zinc immobilization and magnetite formation via ferric oxide reduction by Shewanella putrefaciens 200 Environmental Science and Technology 34 100–106.CrossRefGoogle Scholar
Cui, D. and Eriksen, T., 1996 Reduction of pertechnetate in solution by heterogeneous electron transfer from Fe(II)-containing geological material Environmental Science and Technology 30 2263–2269.CrossRefGoogle Scholar
Dong, H. Kostka, J.E. and Kim, J.W., 2003 Microscopic evidence for microbial dissolution of smectite Clays and Clay Minerals 51 502–512.CrossRefGoogle Scholar
Dong, H. Kukkadapu, R.K. Fredrickson, J.K. Zachara, J.M. Kennedy, D.W. and Kostandarithes, H.M., 2003 Microbial reduction of structural Fe(III) in illite and goethite Environmental Science and Technology 37 1268–1276.CrossRefGoogle Scholar
Elsner, M. Schwarzenbach, R.P. and Haderlein, S.B., 2004 Reactivity of Fe(II) bearing minerals towards reductive transformation of organic contaminants Environmental Science and Technology 38 799–807.CrossRefGoogle Scholar
Favre, F. Bogdal, C. Gavillet, S. and Stucki, J.W., 2006 Changes in the CEC of a soil smectite-kaolinite clay fraction as induced by structural iron reduction and iron coatings dissolution Applied Clay Science 34 95–104.CrossRefGoogle Scholar
Fialips, C.-I. Huo, D. Yan, L. Wu, J. and Stucki, J.W., 2002 Infrared study of reduced and reduced-reoxidized ferruginous smectite Clays and Clay Minerals 50 455–469.CrossRefGoogle Scholar
Foster, W.R. Savins, J.G. and Waite, J.M., 1955 Lattice expansion and rheological behavior of relationships in water-montmorillonite systems Clays and Clay Minerals 395 296–316.Google Scholar
Fredrickson, J.K. Zachara, J.M. Kennedy, D.W. Dong, H. Onstott, T.C. Hinman, N.W. and Shu-mei, L., 1998 Biogenic iron mineralization accompanying the dissimilatory reduction of hydrous ferric oxide by a groundwater bacterium Geochimica et Cosmochimica Acta 62 3239–3257.CrossRefGoogle Scholar
Fredrickson, J.K. Zachara, J.M. Kennedy, D.W. Kukadappu, 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
Furukawa, Y. and O’Reilly, S.E., 2007 Rapid precipitation of amorphous silica in experimental systems with nontronite (NAu-1) and Shewanella oneidensis MR-1 Geochimica et Cosmochimica Acta 71 363–377.CrossRefGoogle Scholar
Gan, H. Bailey, G.W. and Yu, Y.S., 1996 Morphology of lead(II) and chromium(III) reaction products on phyllosilicate surfaces as determined by atomic force microscopy Clays and Clay Minerals 44 734–743.CrossRefGoogle Scholar
Gates, W.P. Slade, P.G. Manceau, A. and Lanson, B., 2002 Site occupancies by iron in nontronites Clays and Clay Minerals 50 223–239.CrossRefGoogle Scholar
Gates, W.P. Wilkinson, H.T. and Stucki, J.W., 1993 Swelling properties of microbially reduced ferruginous smectite Clays and Clay Minerals 41 360–364.CrossRefGoogle Scholar
Giaquinta, D.M. Soderholm, L. Yuchs, S.E. and Wasserman, S.R., 1997 The speciation of uranium in a smectite clay: evidence for catalyzed uranyl reduction Radiochimica Acta 76 113–121.CrossRefGoogle Scholar
Haderlein, S.B. Weissmahr, K.W. and Schwarzenbach, R.P., 1996 Specific adsorption of nitroaromatic explosives and pesticides to clay minerals Environmental Science and Technology 30 612–622.CrossRefGoogle Scholar
Hess, N.J. Xia, Y. Rai, D. and Conradson, S.D., 2004 Thermodynamic model for the solubility of TcO2·xH2O(am) in the aqueous Tc(IV)-Na+-Cl−-H+-OH−-H2O system Journal of Solution Chemistry 33 199–226.CrossRefGoogle Scholar
Hofstetter, T.B. Neumann, A. and Schwarzenbach, R.P., 2006 Reduction of nitroaromatic compounds by Fe(II) species associated with iron-rich smectites Environmental Science and Technology 40 235–242.CrossRefGoogle ScholarPubMed
Hofstetter, T.B. Schwarzenbach, R.P. and Haderlein, S.B., 2003 Reactivity of Fe(II) species associated with clay minerals Environmental Science and Technology 37 519–528.CrossRefGoogle ScholarPubMed
Ilton, E.S. Haiduc, A. Moses, C.O. Heald, S.M. Elbert, D.C. and Veblen, D.R., 2004 Heterogeneous reduction of uranyl by micas: Crystal chemical and solution controls Geochimica et Cosmochimica Acta 68 2417–2435.CrossRefGoogle Scholar
Ilton, E.S. Veblen, D.R. Moses, C.O. and Raeburn, S.P., 1997 The catalytic effect of sodium and lithium ions on coupled sorption-reduction of chromate at the biotite edge-fluid interface Geochimica et Cosmochimica Acta 61 3543–3563.CrossRefGoogle Scholar
Jaisi, D.P. Kukkadapu, R.K. Eberl, D.D. and Dong, H., 2005 Control of Fe(III) site occupancy on the rate and extent of microbial reduction of Fe(III) in nontronite Geochimica et Cosmochimica Acta 69 5429–5440.CrossRefGoogle Scholar
Jaisi, D.P. Dong, H. and Liu, C., 2007 Analysis of Fe(III) reduction kinetics in nontronite Environmental Science and Technology 41 2434–2444.CrossRefGoogle ScholarPubMed
Jaisi, D.P. Dong, H. and Liu, C., 2007 Influence of biogenic Fe(II) on the extent of microbial reduction of Fe(III) in clay minerals nontronite, illite, and chlorite Geochimica et Cosmochimica Acta 71 1145–1158.CrossRefGoogle Scholar
Katoh, S. Danhara, T. Hart, W.K. and Wolde-Gabriel, G., 1999 Use of sodium polytungstate solution in the purification of volcanic glass shards for bulk chemical analysis Natural Human Acta 4 45–54.Google Scholar
Katz, N. and Hazen, T.C. (2005) High throughput analysis of stress response in Shewanella oneidensis MR-1. ().Google Scholar
Keeling, J.L. Raven, M.D. and Gates, W.P., 2000 Geology and characterization of two hydrothermal nontronites from weathered metamorphic rocks at the Uley graphite mine, South Australia Clays and Clay Minerals 48 537–548.CrossRefGoogle Scholar
Khaled, E.M. and Stucki, J.W., 1991 Effects of iron oxidation state on cation fixation in smectites Soil Science Society of America Journal 55 550–554.CrossRefGoogle Scholar
Kim, J.W. Dong, H. Seabaugh, J. Newell, S.W. and Eberl, D.D., 2004 Role of microbes in the smectite-to-illite reaction Science 303 830–832.CrossRefGoogle ScholarPubMed
Komadel, P. Madejová, J. and Stucki, J. W., 2006 Structural Fe(III) reduction in smectites Applied Clay Science 34 88–94.CrossRefGoogle Scholar
Kostka, J.E. Stucki, J.W. Nealson, K.H. and Wu, J., 1996 Reduction of structural Fe(III) in smectite by a pure culture of Shewanella putrefaciens strain MR-1 Clays and Clay Minerals 44 522–529.CrossRefGoogle Scholar
Kostka, J.E. Haefele, E. Viehweger, R. and Stucki, J.W., 1999 Respiration and dissolution of iron(III)-containing clay minerals by bacteria Environmental Science and Technology 33 3127–3133.CrossRefGoogle Scholar
Kukkadapu, R.K. Zachara, J.M. Fredrickson, J.K. McKinley, J.P. Kennedy, D.W. Smith, S.C. and Dong, H., 2006 Reductive biotransformation of Fe in shale-limestone saprolite containing Fe(III) oxides and Fe(II)/Fe(III) phyllosilicates Geochimica et Cosmochimica Acta 70 3662–3676.CrossRefGoogle Scholar
Lear, P.R. and Stucki, J.W., 1987 Intervalence electron transfer and magnetic exchange in reduced nontronite Clays and Clay Minerals 35 373–378.CrossRefGoogle Scholar
Lear, P.R. and Stucki, J.W., 1989 Effects of iron oxidation state on the specific surface area of nontronite Clays and Clay Minerals 37 547–552.CrossRefGoogle Scholar
Lee, K. Kostka, J.E. and Stucki, J.W., 2006 Comparisons of structural Fe reduction in smectites by bacteria and dithionite: An infrared spectroscopic study Clays and Clay Minerals 54 195–208.CrossRefGoogle Scholar
Li, Y.-L. Vali, H. Sears, S.K. Yang, J. Deng, B. and Zhang, C.L., 2004 Iron reduction and alteration of nontronite NAu-2 by a sulfate-reducing bacterium Geochimica et Cosmochimica Acta 68 3251–3260.CrossRefGoogle Scholar
Lieser, K.H. and Bauscher, C., 1988 Technetium in the hydrosphere and in the geosphere: influence of pH of complexing agents and of some minerals on the sorption of technetium Radiochimica Acta 44 125–128.CrossRefGoogle Scholar
Liu, C. Zachara, J.M. Zhong, L. Kukkadupa, R. Szecsody, J.E. and Kennedy, D.W., 2005 Influence of sediment bioreduction and reoxidation on uranium sorption Environmental Science and Technology 39 4125–4133.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 technetium by Fe(III)-reducing bacteria Applied and Environmental Microbiology 66 3743–3749.CrossRefGoogle ScholarPubMed
Luther, G.W. Shellenbarger, A. and Brendel, P.J., 1996 Dissolved organic Fe(III) and Fe(II) complexes in salt marsh porewaters Geochimica et Cosmochima Acta 60 951–960.CrossRefGoogle Scholar
Manceau, A. Lanson, B. Drits, V.A. Chateigner, D. Gates, W.P. Wu, J. Huo, D. and Stucki, J.W., 2000 Oxidation-reduction mechanism of iron in dioctahedral smectites. 1. Crystal chemistry of oxidized reference nontronites American Mineralogist 85 133–152.CrossRefGoogle Scholar
Manceau, A. Lanson, B. Drits, V.A. Chateigner, D. Wu, J. Huo, D. Gates, W.P. and Stucki, J. W., 2000 Oxidation-reduction mechanism of iron in dioctahedral smectites. 2. Structural chemistry of reduced Garfield nontronite American Mineralogist 85 153–172.CrossRefGoogle Scholar
Morris, H.D. Shelton, B. and Ellis, P.D., 1990 27Al NMR spectroscopy of iron bearing montmorillonite clays Journal of Physical Chemistry 94 3121–3129.CrossRefGoogle Scholar
Morrison, S.R., 1980 Electrochemistry at Semiconductor and Oxidized Metal Electrodes New York Plenum.CrossRefGoogle Scholar
NAGRA, 2002 Project Opalinus Clay: Safety report. Demonstration of disposal feasibility for spent fuel, vitrified high-level waste and long lived intermediate level waste Wettingen, Switzerland Nagra.Google Scholar
O’Reilly, S.E. Watkins, J. and Furukawa, Y., 2005 Secondary mineral formation associated with respiration of nontronite, NAu-1 by iron reducing bacteria Geochemical Transactions 6 67–78.CrossRefGoogle ScholarPubMed
O’Reilly, S.E. Furukawa, Y. and Newell, S., 2006 Dissolution and microbial Fe(III) reduction of nontronite (NAu-1) Chemical Geology 235 1–11.CrossRefGoogle Scholar
Qafoku, N.P. Ainsworth, C. Szecsody, J.E. Qafoku, O.S. and Heald, S.M., 2003 Effect of coupled dissolution and redox reactions on Cr(VI)aq attenuation during transport in the sediments under hyperalkaline conditions Environmental Science and Technology 37 3640–3646.CrossRefGoogle ScholarPubMed
Rhoades, J.D. Ingvalson, R.D. and Stumpf, H.T., 1969 Interlayer spacing of expanded clay minerals at various swelling pressures: an X-ray diffraction technique for direct determination Soil Science Society of America Journal 33 473–475.CrossRefGoogle Scholar
Riley, R.G. and Zachara, J.M., 1992 Chemical Contaminants on DOE Lands and Selection of Contaminant Mixtures for Subsurface Science Research Washington, D.C U.S. Department of Energy.Google Scholar
Rozenson, I. and Heller-Kallai, L., 1976 Reduction and oxidation of Fe(III) in dioctahedral smectite-l: reduction with hydrazine and dithionite Clays and Clay Minerals 24 271–282.CrossRefGoogle Scholar
Scott, A.D. and Amonette, J. (1988) The Role of Iron in Mica Weathering. NATO ASI Series, C: pp. 537–623.CrossRefGoogle Scholar
Shen, S. Stucki, J.W., Havlin, J.L. Jacobsen, J. Fixen, P. and Hergert, G., 1994 Effects of iron oxidation state on the fate and behavior of potassium in soils Soil Testing: Prospects for Improving Nutrient Recommendations Madison, Wisconsin Soil Science Society of America 173–185.Google Scholar
Silvester, E. Charlet, L. Tournassat, C. Gehin, A. Greneche, J.-M. and Liger, E., 2005 Redox potential measurements and Mössbauer spectrometry of Fe(II) adsorbed onto Fe(III) (oxyhydr)oxides Geochimica et Cosmochimica Acta 69 4801–4815.CrossRefGoogle Scholar
Skinner, M.F. Zabowski, D. Harrison, R. Lowe, A. and Xue, D., 2001 Measuring the cation exchange capacity of forest soils Communications in Soil Science and Plant Analysis 32 1751–1764.CrossRefGoogle Scholar
Sposito, G. and Prost, R., 1982 Structure of water adsorbed on smectites Chemical Revisions 82 553–573.CrossRefGoogle Scholar
Stookey, L.L., 1970 Ferrozine — a new spectrophotometric reagent for iron Analytical Chemistry 42 779–781.CrossRefGoogle Scholar
Stucki, J.W., Bergaya, F. Lagaly, G. and Theng, B.K.G., 2006 Iron redox processes in clay minerals Handbook of Clay Science Amsterdam Elsevier 429–482.Google Scholar
Stucki, J.W. and Huo, D. (1996) Effects of Cation Competition on Potassium Fixation. Proceedings of the Illinois Fertilizer Conference, Illinois.Google Scholar
Stucki, J.W. and Kostka, J.E., 2006 Microbial reduction of iron in smectite Comptes Rendus Geoscience 338 468–475.CrossRefGoogle Scholar
Stucki, J.W. Golden, D.C. and Roth, C.B., 1984 Preparation and handling of dithionite-reduced smectite suspensions Clays and Clay Minerals 32 191–197.CrossRefGoogle Scholar
Stucki, J.W. Golden, D.C. and Roth, C.B., 1984 Effect of reduction and reoxidation of structural iron on the surface charge and dissolution of dioctahedral smectites Clays and Clay Minerals 32 350–356.CrossRefGoogle Scholar
Stucki, J.W. Lee, K. Zhang, L. and Larson, R.A., 2002 The effects of iron oxidation state on the surface and structural properties of smectites Pure and Applied Chemistry 74 2079–2092.CrossRefGoogle Scholar
Stumm, W. and Morgan, J.J., 1996 Aquatic Chemistry New York Wiley.Google Scholar
Taylor, R.W. Shen, S. Bleam, W.F. and Tu, S.I., 2000 Chromate removal by dithionite-reduced clays: evidence from direct X-ray absorption near edge spectroscopy (XANES) of chromate reduction at clay surfaces Clays and Clay Minerals 48 648–654.CrossRefGoogle Scholar
Viani, B.E. Low, P.F. and Roth, C.B., 1983 Direct measurement of the relation between interlayer force and interlayer distance in the swelling of montmorillonite Colloidal and Interface Science 96 229–244.CrossRefGoogle Scholar
Weissmahr, K.W. Haderlein, S.B. Schwarzenbach, R.P. Hany, R. and Nuesch, R., 1996 In situ spectroscopic investigations of adsorption mechanisms of nitroaromatic compounds at clay minerals Environmental Science and Technology 31 240–247.CrossRefGoogle Scholar
Wildung, R.E. Gorby, Y.A. Krupka, K.M. Hess, N.J. Li, S.W. Plymale, A.E. McKinley, J.P. and Fredrickson, J.K., 2000 Effect of electron donor and solution chemistry on products of dissimilatory reduction of technetium by Shewanella putrefaciens. Applied and Environmental Microbiology 66 2451–2460.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 and Ecology 49 151–162.CrossRefGoogle ScholarPubMed
Williams, A.G.B. and Scherer, M.M., 2004 Spectroscpoic evidence for Fe(II)-Fe(III) electron transfer at iron oxide-water interface Environmental Science and Technology 38 4782–4790.CrossRefGoogle Scholar
Wu, J. Roth, C.B. and Low, P.F., 1988 Biological reduction of structural iron in sodium-nontronite Soil Science Society of America Journal 52 295–296.CrossRefGoogle Scholar
Zachara, J.M. Fredrickson, J.K. Li, S.W. Kennedy, D.W. Smith, S.C. and Gassman, P.L., 1998 Bacterial reduction of crystalline Fe(III) oxides in single phase suspension and subsurface materials American Mineralogist 83 1426–1443.CrossRefGoogle Scholar
Zachara, J.M. Heald, S.M. Jeon, B.-H. Kukkadapu, R.K. Dohnalkova, A.C. McKinley, J.P. Moore, D.A. and Liu, C., 2007 Reduction of pertechnetate [Tc(VII)] by aqueous Fe(II) and the nature of solid phase redox products Geochimica et Cosmochimica Acta 71 2137–2157.CrossRefGoogle Scholar