Clays and Clay Minerals

, Volume 56, Issue 2, pp 175–189 | Cite as

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

  • Deb P. Jaisi
  • Hailiang DongEmail author
  • John P. Morton


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 \({\rm{Fe}}{\left( {{\rm{II}}} \right)_{{\rm{N}}{{\rm{H}}_4}{\rm{Cl}}}}\)), 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: \({\rm{Fe}}_{\left( {{\rm{ab}}} \right)}^{2 + }\), Fe(II)acetate, \({\rm{Fe}}{\left( {{\rm{II}}} \right)_{{\rm{N}}{{\rm{H}}_4}{\rm{Cl}}}}\), 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 \({\rm{Fe}}{\left( {{\rm{II}}} \right)_{{\rm{N}}{{\rm{H}}_4}{\rm{Cl}}}}\) 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 \({\rm{Fe}}{\left( {{\rm{II}}} \right)_{{\rm{N}}{{\rm{H}}_4}{\rm{Cl}}}}\). 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.

Key Words

Fe(III) Reduction Fe(II) partitioning Shewanella putrefaciens CN32 NAu-2 Tc(VII) Reduction 


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  1. 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.Google Scholar
  2. Amonette, J.E. (2003) Iron redox chemistry of clays and oxides: environmental applications. Pp. 89–148 in: Electrochemical Properties of Clays (A. Fitch, editor). The Clay Minerals Society, Aurora, Colorado, USA.Google Scholar
  3. Ammonette, J.E. and Scott A.D. (1995) Oxidative weathering of trioctahedral micas by buffered H2O2 solutions. Clays Controlling the Environment (G.J. Churchman, editor). CSIRO Publishing, Melbourne, pp. 355–361.Google Scholar
  4. 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.Google Scholar
  5. 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.Google Scholar
  6. 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.Google Scholar
  7. 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.Google Scholar
  8. Bratu, C., Bratu, G., Galateanu, I., and Roman, M. (1975) Study of lower valence states of technetium. Journal of Radioanalytical Chemistry, 26, 5–16.Google Scholar
  9. Brusic, V. (1972) Passivation and passivity. Pp. 1–80 in: The Anodic Behavior of Metals and Semiconductors Series (J.W. Diggle, editor). Marcel and Dekker, Inc., New York.Google Scholar
  10. 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.Google Scholar
  11. 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.Google Scholar
  12. 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.Google Scholar
  13. Cantrell, K.J., Serne, R.J., and Last, G.V. (2003) Hanford Contaminant Distribution Coefficient Database and Users Guide. Pacific Northwest National Laboratory, Richland, Washington.Google Scholar
  14. 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.Google Scholar
  15. 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.Google Scholar
  16. 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.Google Scholar
  17. 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.Google Scholar
  18. 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.Google Scholar
  19. 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.Google Scholar
  20. 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.Google Scholar
  21. 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.Google Scholar
  22. Dong, H., Kostka, J.E., and Kim, J.W. (2003a) Microscopic evidence for microbial dissolution of smectite. Clays and Clay Minerals, 51, 502–512.Google Scholar
  23. Dong, H., Kukkadapu, R.K., Fredrickson, J.K., Zachara, J.M., Kennedy, D.W., and Kostandarithes, H.M. (2003b) Microbial reduction of structural Fe(III) in illite and goethite. Environmental Science and Technology, 37, 1268–1276.Google Scholar
  24. 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.Google Scholar
  25. 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.Google Scholar
  26. 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.Google Scholar
  27. 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
  28. 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.Google Scholar
  29. 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.Google Scholar
  30. 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.Google Scholar
  31. 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.Google Scholar
  32. 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.Google Scholar
  33. 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.Google Scholar
  34. 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.Google Scholar
  35. 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.Google Scholar
  36. 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.Google Scholar
  37. 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.Google Scholar
  38. 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.Google Scholar
  39. 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.Google Scholar
  40. 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.Google Scholar
  41. 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.Google Scholar
  42. Jaisi, D.P., Dong, H., and Liu, C. (2007a) Analysis of Fe(III) reduction kinetics in nontronite. Environmental Science and Technology, 41, 2434–2444.Google Scholar
  43. Jaisi, D.P., Dong, H., and Liu, C. (2007b) 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.Google Scholar
  44. 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
  45. Katz, N. and Hazen, T.C. (2005) High throughput analysis of stress response in Shewanella oneidensis MR-1. (
  46. 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.Google Scholar
  47. 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.Google Scholar
  48. 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.Google Scholar
  49. Komadel, P., Madejová, J., and Stucki, J. W. (2006) Structural Fe(III) reduction in smectites. Applied Clay Science, 34, 88–94.Google Scholar
  50. 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.Google Scholar
  51. 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.Google Scholar
  52. 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.Google Scholar
  53. Lear, P.R. and Stucki, J.W. (1987) Intervalence electron transfer and magnetic exchange in reduced nontronite. Clays and Clay Minerals, 35, 373–378.Google Scholar
  54. 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.Google Scholar
  55. 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.Google Scholar
  56. 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.Google Scholar
  57. 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.Google Scholar
  58. 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.Google Scholar
  59. 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.Google Scholar
  60. 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.Google Scholar
  61. Manceau, A., Lanson, B., Drits, V.A., Chateigner, D., Gates, W.P., Wu, J., Huo, D., and Stucki, J.W. (2000a) Oxidation-reduction mechanism of iron in dioctahedral smectites. 1. Crystal chemistry of oxidized reference nontronites. American Mineralogist, 85, 133–152.Google Scholar
  62. Manceau, A., Lanson, B., Drits, V.A., Chateigner, D., Wu, J., Huo, D., Gates, W.P., and Stucki, J. W. (2000b) Oxidation-reduction mechanism of iron in dioctahedral smectites. 2. Structural chemistry of reduced Garfield nontronite. American Mineralogist, 85, 153–172.Google Scholar
  63. 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.Google Scholar
  64. Morrison, S.R. (1980) Electrochemistry at Semiconductor and Oxidized Metal Electrodes. Plenum, New York.Google Scholar
  65. NAGRA (2002) Project Opalinus Clay: Safety report. Demonstration of disposal feasibility for spent fuel, vitrified high-level waste and long lived intermediate level waste. NAGRA Technical Report NTB 02-05, Nagra, Wettingen, Switzerland.Google Scholar
  66. 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.Google Scholar
  67. 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.Google Scholar
  68. 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.Google Scholar
  69. 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.Google Scholar
  70. Riley, R.G. and Zachara, J.M. (1992) Chemical Contaminants on DOE Lands and Selection of Contaminant Mixtures for Subsurface Science Research. U.S. Department of Energy, Washington, D.C.Google Scholar
  71. 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.Google Scholar
  72. Scott, A.D. and Amonette, J. (1988) The Role of Iron in Mica Weathering. NATO ASI Series, C: pp. 537–623.Google Scholar
  73. Shen, S. and Stucki, J.W. (1994) Effects of iron oxidation state on the fate and behavior of potassium in soils. Pp 173–185 in: Soil Testing: Prospects for Improving Nutrient Recommendations (J.L. Havlin, J. Jacobsen, P. Fixen, and G. Hergert, editors). SSSA Special Publication, 40. Soil Science Society of America, Madison, Wisconsin.Google Scholar
  74. 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.Google Scholar
  75. 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.Google Scholar
  76. Sposito, G. and Prost, R. (1982) Structure of water adsorbed on smectites. Chemical Revisions, 82, 553–573.Google Scholar
  77. Stookey, L.L. (1970) Ferrozine — a new spectrophotometric reagent for iron. Analytical Chemistry, 42, 779–781.Google Scholar
  78. Stucki, J.W. (2006) Iron redox processes in clay minerals. Pp. 429–482 in: Handbook of Clay Science (F. Bergaya, G. Lagaly, and B.K.G. Theng, editors). Elsevier, Amsterdam.Google Scholar
  79. Stucki, J.W. and Huo, D. (1996) Effects of Cation Competition on Potassium Fixation. Proceedings of the Illinois Fertilizer Conference, Illinois.Google Scholar
  80. Stucki, J.W. and Kostka, J.E. (2006) Microbial reduction of iron in smectite. Comptes Rendus Geoscience, 338, 468–475.Google Scholar
  81. Stucki, J.W., Golden, D.C., and Roth, C.B. (1984a) Preparation and handling of dithionite-reduced smectite suspensions. Clays and Clay Minerals, 32, 191–197.Google Scholar
  82. Stucki, J.W., Golden, D.C., and Roth, C.B. (1984b) Effect of reduction and reoxidation of structural iron on the surface charge and dissolution of dioctahedral smectites. Clays and Clay Minerals, 32, 350–356.Google Scholar
  83. 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.Google Scholar
  84. Stumm, W. and Morgan, J.J. (1996) Aquatic Chemistry. Wiley, New York.Google Scholar
  85. 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.Google Scholar
  86. 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.Google Scholar
  87. 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.Google Scholar
  88. 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.Google Scholar
  89. 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.Google Scholar
  90. 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.Google Scholar
  91. 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.Google Scholar
  92. 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.Google Scholar
  93. 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.Google Scholar

Copyright information

© The Clay Minerals Society 2008

Authors and Affiliations

  • Deb P. Jaisi
    • 1
    • 2
  • Hailiang Dong
    • 1
    Email author
  • John P. Morton
    • 1
  1. 1.Department of GeologyMiami UniversityOxfordUSA
  2. 2.Department of Geology and GeophysicsYale UniversityNew HavenUSA

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