Skip to main content
SpringerLink
Log in

Molecular Structure and Binding Sites of Cobalt(II) Surface Complexes on Kaolinite from X-Ray Absorption Spectroscopy

  • Published:
Clays and Clay Minerals

Abstract

X-ray absorption spectroscopy (XAS) was used to determine the local molecular environment of Co(II) surface complexes sorbed on three different kaolinites at ambient temperature and pressure in contact with an aqueous solution. Interatomic distances and types and numbers of backscattering atoms have been derived from analysis of the extended X-ray absorption fine structure (EXAFS). These data show that, at the lowest amounts of Co uptake on kaolinite (0.20–0.32 µmol m−2), Co is surrounded by ≈6 O atoms at 2.04–2.08 Å and a small number or Al or Si atoms (N = 0.6–1.5) at two distinct distances, 2.67–2.72 Å and 3.38–3.43 Å. These results indicate that Co bonds to the kaolinite surface as octahedrally coordinated, bidentate inner-sphere mononuclear complexes at low surface coverages, confirming indirect evidence from solution studies that a fraction of sorbed Co forms strongly bound complexes on kaolinite. In addition to inner-sphere complexes identified by EXAFS spectroscopy, solution studies provide evidence for the presence of weakly bound, outer-sphere Co complexes that cannot be detected directly by EXAFS. One orientation for inner-sphere complexes indicated by XAS is bidentate bonding of Co to oxygen atoms at two Al-O-Si edge sites or an Al-O-Si and Al-OH (inner hydroxyl) edge site, i.e., corner-sharing between Co octahedra and Al and Si polyhedra. At slightly higher surface sorption densities (0.51–0.57/ µmol m−2), the presence of a small number of second-neighbor Co atoms (average NCo < 1) at 3.10–3.13 Å indicates the formation of oxy- or hydroxy-bridged, multinuclear surface complexes in addition to mononuclear complexes. At these surface coverages, Co-Co and Co-Al/Si distances derived from EXAFS are consistent with edge-sharing between Co and Al octahedra on either edges or (001) faces of the aluminol sheet in kaolinite. Multinuclear complexes form on kaolinite at low surface sorption densities equivalent to < 5% coverage by a monolayer of oxygen-ligated Co octahedra over the N2-BET surface area. These spectroscopic results have several implications for macroscopic modeling of metal ion uptake on kaolinite: 1) Primary binding sites on the kaolinite surface at low uptake are edge, non-bridging Al-OH inner hydroxyl sites and edge Al-O-Si bridging oxygen sites, not Si-OH sites typically assumed in sorption models; 2) specific adsorption of Co is via bidentate, inner-sphere complexation; and 3) at slightly higher uptake but still a small fraction of monolayer coverage, formation of Co multinuclear complexes, primarily edge-sharing with Al-OH octahedra, begins to dominate sorption.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Ashley, C. A. and Doniach, S. (1975) Theory of extended X-ray absorption fine structure (EXAFS) in crystalline solids: Phys. Rev. B11, 1279–1288.

    Google Scholar 

  • Baes Jr., C. F. and Mesmer, R. E. (1976) The Hydrolysis of Cations: John Wiley & Sons, New York, 489 pp.

    Google Scholar 

  • Bancroft, G. M. and Hyland, M. M. (1990) Spectroscopic studies of adsorption/reduction reactions of aqueous metal complexes on sulphide surfaces: in Mineral- Water Interface Geochemistry, M. F. Hochella Jr. and A. F. White, eds., Reviews in Mineralogy 23, Mineralogical Society of America, Washington, D.C., 511–558.

    Google Scholar 

  • Bish, D. L. and Von Dreele, R. B. (1989) Rietveld refinement of non-hydrogen atomic positions in kaolinite: Clays & Clay Minerals 37, 289–296.

    Google Scholar 

  • Bleam, W. F. and McBride, M. B. (1985) Cluster formation vs. isolated-site adsorption. A study of Mn(II) and Mg(II) adsorption on boehmite and goethite: J. Colloid Interface Sci. 103, 124–132.

    Google Scholar 

  • Bol, W., Gerrits, G. J. A., and van Panthaleon van Eck, C. L. (1970) The hydration of divalent cations in aqueous solution. An X-ray investigation with isomorphous replacement: J. Appl. Cryst. 3, 486–492.

    Google Scholar 

  • Bolland, M. D. A., Posner, A. M., and Quirk, J. P. (1976) Surface charge in kaolinites in aqueous suspension: Aust. J. Soil Res. 14, 197–216.

    Google Scholar 

  • Bolland, M. D. A., Posner, A. M., and Quirk, J. P. (1980) pH-independent and pH-dependent surface charges on kaolinite: Clays & Clay Minerals 28, 412–418.

    Google Scholar 

  • Brown Jr., G. E. (1990) Spectroscopic studies of chemisorption reaction mechanisms at oxide-water interfaces: in Mineral-Water Interface Geochemistry, M. F. Hochella Jr. and A. F. White, eds., Reviews in Mineralogy 23, Mineralogical Society of America, Washington, D.C., 309–363.

    Google Scholar 

  • Brown Jr., G. E., Calas, G., Waychunas, G. A., and Petiau, J. (1988) X-ray absorption spectroscopy and its applications in mineralogy and geochemistry: in Spectroscopic tMethods in Mineralogy and Geology, F. C. Hawthorne ed., Reviews in Mineralogy 18, Mineralogical Society of America, Washington, D.C., 431–512.

    Google Scholar 

  • Brown Jr., G. E. and Parks, G. A. (1989) Synchrotron-based x-ray absorption studies of cation environments in earth materials: Reviews of Geophysics 27, 519–533.

    Google Scholar 

  • Brown Jr., G. E., Parks, G. A., and Chisholm-Brause, C. J. (1989) In-situ x-ray absorption spectroscopic studies of ions at oxide-water interfaces: Chimia 43, 248–256.

    Google Scholar 

  • Calas, G. and Petiau, J. (1983) Coordination of iron in oxide glasses through high-resolution K-edge spectra: Information from the preedge: Solid State Comm. 48, 625–629.

    Google Scholar 

  • Carroll, S. A. and Walther, J. V. (1990) Temperature dependence of kaolinite dissolution rates. Amer. J. Sci. 290, 797–810.

    Google Scholar 

  • Carroll-Webb, S. A. and Walther, J. V. (1988) A surface complex reaction model for the pH-dependence of corun-dum and kaolinite dissolution rates: Geochim. Cosmochim. Acta 52, 2609–2623.

    Google Scholar 

  • Charlet, L. and Manceau, A. (1992) X-ray absorption spectroscopic study of the sorption of Cr(H) at the oxide-water interface. II. Adsorption, coprecipitation, and surface precipitation on hydrous ferric oxide: J. Colloid Interface Sci. 148, 443–458.

    Google Scholar 

  • Chisholm-Brause, C. J. (1991) Spectroscopic and equilibrium study of cobalt(II) sorption complexes at oxide/water interfaces: Doctoral thesis, Stanford University, Stanford, California, 118 pp.

    Google Scholar 

  • Chisholm-Brause, C. J., Hayes, K. F., Roe, A. L., Brown Jr., G. E., Parks, G. A., and Leckie, J. O. (1990a) Spectroscopic investigation of Pb(II) complexes at the γ-Al2O3/ water interface: Geochim. Cosmochim. Acta 54, 1897–1909.

    Google Scholar 

  • Chisholm-Brause, C. J., O’Day, P. A., Brown Jr., G. E., and Parks, G. A. (1990b) Evidence for multinuclear metalion complexes at solid/water interfaces from X-ray absorption spectroscopy: Nature 348, 528–530.

    Google Scholar 

  • Combes, J. M., Manceau, A., Calas, G., and Bottero, J. Y. (1989) Formation of ferric oxides from aqueous solutions: A polyhedral approach by X-ray absorption spectroscopy. I. Hydrolysis and formation of ferric gels: Geochim. Cosmochim. Acta 53, 583–594.

    Google Scholar 

  • Combes, J. M., Manceau, A., and Calas, G. (1990) Formation of ferric oxides from aqueous solutions: A poly-hedral approach by X-ray absorption spectroscopy. II. Hematite formation from ferric gels: Geochim. Cosmochim. Acta 54, 1083–1091.

    Google Scholar 

  • Cowan, C. E., Zachara, J. M., Smith, S. C., and Resch, C. T. (1992) Individual sorbent contributions to cadmium sorp-tion on ultisols of mixed mineralogy: Soil Sci. Soc. Am. J. 56, 1084–1094.

    Google Scholar 

  • Cramer, S. P. and Hodgson, K. O. (1979) X-ray absorption spectroscopy: A new structural method and its applications to bioinorganic chemistry: Prog. Inorg. Chem. 25, 1–39.

    Google Scholar 

  • Crozier, E. D., Rehr, J. J., and Ingalls, R. (1988) Amorphous and liquid systems: in X-ray Absorption: Principles, Applications, Techniques of EXAFS, SEXAFS, and XANES, D. C. Koningsberger and R. Prins, eds., Chemical Analysis 92, John Wiley & Sons, New York, 373–442.

    Google Scholar 

  • Davis, J. A. and Hayes, K. F., eds. (1986) Geochemical Processes at Mineral Surfaces, ACS Symposium Series 323, 683 pp.

  • Davis, J. A. and Kent, D. B. (1990) Surface complexation modeling in aqueous geochemistry: in Mineral- Water Interface Geochemistry, M. F Hochella Jr. and A. F. White, eds., Reviews in Mineralogy 23, Mineralogical Society of America, Washington, D.C., 177–260.

    Google Scholar 

  • Davison, N., McWhinnie, W. R., and Hooper, A. (1991) X-ray photoelectron spectroscopy study of cobalt(II) and nickel(II) sorbed on hectorite and montmorillonite: Clays & Clay Minerals 39, 22–27.

    Google Scholar 

  • Dent, A. J., Ramsay, J. D. F., and Swanton, W. (1992) An EXAFS study of uranyl ion in solution and sorbed onto silica and montmorillonite clay colloids: J.Colloid Interface Sci. 150, 45–60.

    Google Scholar 

  • Dillard, J. G. and Koppelman, M. H. (1982) X-ray photoelectron spectroscopic (XPS) surface characterization of cobalt on the surface of kaolinite: J. Colloid Interface Sci. 87, 46–55.

    Google Scholar 

  • Dzombak, D. A. and Morel, F. M. M. (1990) Surface Complexation Modeling: Hydrous Ferric Oxide: John Wiley & Sons, New York, 393 pp.

    Google Scholar 

  • Farley, K. J., Dzombak, D. A., and Morel, F. M. M. (1985) A surface precipitation model for the sorption of cations on metal oxides: J. Colloid Interface Sci. 106, 226–242.

    Google Scholar 

  • Farrah, H., Hatton, D., and Pickering, W. F. (1980) The affinity of metal ions for clay surfaces: Chem. Geology 28, 55–56.

    Google Scholar 

  • Feitknecht, W. and Schindler, P. (1963) Solubility constants of metal oxides, metal hydroxides and metal hydroxide salts in aqueous solution: Pure Applied Chem. 6, 130–199.

    Google Scholar 

  • Ferris, A. P. and Jepson, W. B. (1975) The exchange capacities of kaolinite and the preparation of homoionic clays: J. Colloid Interface Sci. 51, 245–259.

    Google Scholar 

  • Follet, E. A. C. (1965) The retention of amorphous, colloidal “ferric hydroxide” by kaolinites: J. Soil Sci. 16, 334–341.

    Google Scholar 

  • Fordham, A. W. (1973) The location of iron-55, strontium-8 5, and iodide-125 sorbed by kaolinite and dickite particles: Clays & Clay Minerals 21, 175–184.

    Google Scholar 

  • Gayer, K. H. and Garrett, A. B. (1950) The solubility of cobalt hydroxide, Co(OH)2, in solutions of hydrochloric acid and sodium hydroxide at 25°C: J. Amer. Chem. Soc. 72, 3921–3923.

    Google Scholar 

  • Giese Jr., R. F. (1988) Kaolin minerals: Structures and stabilities: in Hydrous Phyllosilicates, S. W. Bailey, ed., Reviews in Mineralogy 19, Mineralogical Society of America, Washington, D.C., 29–66.

    Google Scholar 

  • Grim, R. E. (1968) Clay Mineralogy: McGraw-Hill, New York, 596 pp.

    Google Scholar 

  • Hahn, J. E. and Hodgson, K. O. (1983) Polarized x-ray absorption spectroscopy: in Inorganic Chemistry: Toward the 21st Century, M. H. Chisholm, ed., ACS Symposium Series 211, Washington, D.C., 432–444.

    Google Scholar 

  • Hayes, K. F. and Leckie, J. O. (1987) Modeling ionic strength effects on cation adsorption at hydrous oxide/solution interfaces: J. Colloid Interface Sci. 115, 564–572.

    Google Scholar 

  • Hayes, K. F., Roe, A. L., Brown Jr., G. E., Hodgson, K. O., Leckie, J. O., and Parks, G. A. (1987) In situ X-ray absorption study of surface complexes at oxide/water interfaces: Selenium oxyanions on α-FeOOH: Science 238,783–786.

    Google Scholar 

  • Heald, S. M. and Stern, E. A. (1977) Anisotropic X-ray absorption in layered compounds: Phys. Rev. B16, 5549–5559.

    Google Scholar 

  • Hochella Jr., M. F. and White, A. F., eds. (1990) Mineral-Water Interface Geochemistry, Reviews in Mineralogy 23, Mineralogical Society of America, Washington, D.C., 603 pp.

  • Jackson, M. L. (1975) Soil Chemical Analysis—Advanced Course, 2nd ed., published by the author, Department of Soil Science, University of Wisconsin, Madison, Wisconsin, 894 pp.

    Google Scholar 

  • Jepson, W. B. and Rowse, J. B. (1975) The composition of kaolinite—an electron microscope microprobe study: Clays & Clay Minerals 28, 310–317.

    Google Scholar 

  • Koningsberger, D. C. and Prins, R., eds. (1988) X-ray Ab-sorption: Principles, Applications, Techniques of EXAFS, SEXAFS, and XANES, Chemical Analysis 92, John Wiley & Sons, New York, 673 pp.

    Google Scholar 

  • Koppelman, M. H. and Dillard, J. G. (1975) An ESCA study of sorbed metal ions on clay minerals: in Marine Chemistry in the Coastal Environment, T. M. Church, ed., ACS Symposium Series 18, Washington, D.C., 186–201.

    Google Scholar 

  • Koppelman, M. H. and Dillard, J. G. (1977) A study of the adsorption of Ni(II) and Cu(II) by clay minerals: Clays & Clay Minerals 25, 457–462.

    Google Scholar 

  • Koppelman, M. H., Emerson, A. B., and Dillard, J. G. (1980) Adsorbed Cr(III) on chlorite, illite, and kaolinite: An X-ray photoelectron spectroscopic study: Clays & Clay Minerals 28, 119–124.

    Google Scholar 

  • Lee, S. Y., Jackson, M. L., and Brown, J. L. (1975) Micaceous occlusions in kaolinite observed by ultramicrotomy and high resolution electron microscopy: Clays & Clay Minerals 23, 125–129.

    Google Scholar 

  • Lim, C. H., Jackson, M. L., Koons, R. D., and Helmke, P. A. (1980) Kaolins: Sources of differences in cation-exchange capacities and cesium retention: Clays & Clay Minerals 28, 223–229.

    Google Scholar 

  • Lotmar, W. and Feitknecht, W. (1936) Uber anderungen der ionenabstande in hydroxyd-schichtengittern: Z. Krist. A93, 368–378.

    Google Scholar 

  • Lytle, F. W. (1989) Experimental X-ray absorption spectroscopy: in Applications of Synchrotron Radiation, H. Winick et al., eds., Gordon and Breach Science Publ., 135–223.

    Google Scholar 

  • Lytle, F. W., Sandstrom, D. R., Marques, E. C, Wong, J., Spiro, C. L., Huffman, G. P., and Huggins, F. E. (1984) Measurement of soft x-ray absorption spectra with a fluo-rescence ion chamber detector: Nucl. Instr. and Meth. 226, 542–548.

    Google Scholar 

  • Manceau, A., Bonnin, D., Kaiser, P., and Fretigny, C. (1988) Polarized EXAFS of biotite and chlorite: Phys. Chem. Minerals 16, 180–185.

    Google Scholar 

  • Manceau, A. and Charlet, L. (1992) X-ray absorption spectroscopic study of the sorption of Cr(II) at the oxide-water interface. I. Molecular mechanism of Cr(JII) oxidation on Mn oxides: J. Colloid Interface Sci. 148, 425–442.

    Google Scholar 

  • Manceau, A., Charlet, L., Boisset, M. C, Didier, B., and Spadini, L. (1992) Sorption and speciation of heavy metals on hydrous Fe and Mn oxides. From microscopic to macroscopic: Applied Clay Sci. 7, 201–223.

    Google Scholar 

  • Manceau, A. and Combes, J. M. (1988) Structure of Mn and Fe oxides and oxyhydroxides: A topological approach by EXAFS: Phys. Chem. Minerals 15, 283–295.

    Google Scholar 

  • May, H. M., Kinniburgh, D. G., Helmke, P. A., and Jackson, M. L. (1986) Aqueous dissolution, solubilities and thermodynamic stabilities of common aluminosilicate clay minerals: Kaolinite and smectites: Geochim. Cosmochim. Acta 50, 1667–1677.

    Google Scholar 

  • McBride, M. B. (1976) Origin and position of exchange sites in kaolinite: An ESR study: Clays & Clay Minerals 24, 88–92.

    Google Scholar 

  • McBride, M. B. (1978) Copper(H) interactions with kaolinite: Factors controlling adsorption. Clays & Clay Minerals 26, 101–106.

    Google Scholar 

  • McBride, M. B., Fraser, A. R., and McHardy, W. J. (1984) Cu2+ interaction with microcrystalline gibbsite. Evidence for oriented chemisorbed copper ions: Clays & Clay Minerals 32, 12–18.

    Google Scholar 

  • McMaster, W. H., Del Grande, N. K., Mallett, J. H., and Hubbell, J. H. (1969) Compilation of x-ray cross sections III: U.S. Atom. Energ. Comm. UCRL-50174.

    Google Scholar 

  • Motschi, H. (1984) Correlation of EPR parameters with thermodynamic stability constants for copper(II) complexes. Copper(II)-EPR as a probe for the surface complexation at the oxide/water interface: Colloids Surf. 9, 333–347.

    Google Scholar 

  • Motschi, H. (1987) Aspects of the molecular structure in surface complexes; spectroscopic investigations: in Aquatic Surface Chemistry, W. Stumm, ed., Wiley-Interscience, New York, 111–125.

    Google Scholar 

  • Mustre de Leon, J., Rehr, J. J., and Zabinsky, S. I. (1991) Ab initio curved-waved x-ray-absorption fine structure: Phys. Rev. B44, 4146–4156.

    Google Scholar 

  • O’Day, P. A. (1992) Structure, bonding, and site preference of cobalt(H) sorption complexes on kaolinite and quartz from solution and spectroscopic studies: Doctoral thesis, Stanford University, Stanford, California, 208 pp.

    Google Scholar 

  • O’Day, P. A., Brown Jr., G. E., and Parks, G. A. (1991) EXAFS study of aqueous Co(II) sorption complexes on kaolinite and quartz surfaces: in X-ray Absorption Fine Structure, S. S. Hasnain, ed., Ellis Horwood Ltd., London, 260–262.

    Google Scholar 

  • O’Day, P. A., Brown Jr., G. E., and Parks, G. A. (1994a) X-ray absorption spectroscopy of cobalt(II) multinuclear surface complexes and surface precipitates on kaolinite: J.Colloid Interface Sci., in press.

    Google Scholar 

  • O’Day, P. A., Rehr, J. J., Zabinsky, S. I., and Brown Jr., G. E. (1994b) Extended X-ray absorption fine structure (EX-AFS) analysis of disorder and multiple-scattering in complex crystalline solids: J. Amer. Chem. Soc, in press.

    Google Scholar 

  • Parfitt, R. L. (1978) Anion adsorption by soils and soil materials: Adv. Agron. 30, 1–50.

    Google Scholar 

  • Rehr, J. J. and Albers, R. C. (1990) Scattering-matrix formulation of curved-wave multiple-scattering theory: Application to X-ray-absorption fine structure: Phys. Rev. B41, 8139–8149.

    Google Scholar 

  • Rehr, J. J., Albers, R. C., and Zabinsky, S. I. (1992) High-order multiple-scattering calculations of X-ray-absorption fine structure: Phys. Rev. Lett. 69, 3937–3400.

    Google Scholar 

  • Rehr, J. J., Mustre de Leon, J., Zabinsky, S. I., and Albers, R. C. (1991) Theoretical X-ray absorption fine structure standards: J. Amer. Chem. Soc. 113, 5135–5140.

    Google Scholar 

  • Report on the international workshops on standards and criteria in XAFS (1991): in X-ray Absorption Fine Structure, S. S. Hasnain, ed., Ellis Horwood Ltd., London, 751–770.

  • Riese, A. C. (1982) Adsorption of radium and thorium onto quartz and kaolinite: A comparison of solution/surface equilibria models: Doctoral thesis, Colorado School of Mines, Golden, Colorado, 210 pp.

    Google Scholar 

  • Roe, A. L., Hayes, K. F., Chisholm-Brause, C. J., Brown Jr., G. E., Parks, G. A., and Leckie, J. O. (1991) X-ray absorption study of lead complexes at α-FeOOH/water interfaces: Langmuir 7, 367–373.

    Google Scholar 

  • Sayers, D. E. and Bunker, B. A. (1988) Data analysis: in X-ray Absorption: Principles, Applications, Techniques of EXAFS, SEXAFS, and XANES, D. C. Koningsberger and R. Prins, eds., Chemical Analysis 92, John Wiley & Sons, New York, 211–253.

    Google Scholar 

  • Sayers, D. E., Stern, E. A., and Lytle, F. W. (1971) New technique for investigating noncrystalline structures Fourier analysis of the Extended X-ray-Absorption Fine Structure: Phys. Rev. Lett. 27, 1204–1207.

    Google Scholar 

  • Schenk, C. V., Dillard, J. G., and Murray, J. W. (1983) Surface analysis and the adsorption of Co(II) on goethite: J. Colloid Interface Sci. 95, 398–109.

    Google Scholar 

  • Schindler, P. W., Liechti, P., and Westall, J. C. (1987) Adsorption of copper, cadmium, and lead from aqueous solution to the kaolinite/water interface: Neth. J. Agri. Sci. 35, 219–230.

    Google Scholar 

  • Schindler, P. W. and Stumm, W. (1987) The surface chemistry of oxides, hydroxides, and oxide minerals: in Aquatic Surface Chemistry, W. Stumm, ed., Wiley-Interscience, New York, 83–110.

    Google Scholar 

  • Schofield, R. K. and Samson, H. R. (1954) Flocculation of kaolinite due to the attraction of oppositely charged crystal faces: Faraday Soc. Diss. 18, 135–145.

    Google Scholar 

  • Singh, S. P. N. and Mattigod, S. V. (1992) Modeling boron adsorption on kaolinite: Clays & Clay Minerals 40, 192–205.

    Google Scholar 

  • Sposito, G. (1984) The Surface Chemistry of Soils: Oxford University Press, New York, 234 pp.

    Google Scholar 

  • Sposito, G. (1989) The Chemistry of Soils: Oxford University Press, New York, 277 pp.

    Google Scholar 

  • Stern, E. A. (1988) Theory of EXAFS: in X-ray Absorption: Principles, Applications, Techniques of EXAFS, SEXAFS, and XANES, D. C. Koningsberger and R. Prins, eds., Chemical Analysis 92, John Wiley & Sons, New York, 3–51.

    Google Scholar 

  • Stern, E. A., Sayers, D. E., and Lytle, F. W. (1975) Extended X-ray absorption fine structure technique. III. Determination of physical parameters: Phys. Rev. B11, 4836–4846.

    Google Scholar 

  • Stumm, W., ed. (1987) Aquatic Surface Chemistry: Wiley-Interscience, New York, 520 pp.

    Google Scholar 

  • Stumm, W. (1992) Chemistry of the Solid-Water Interface: Wiley-Interscience, New York, 428 pp.

    Google Scholar 

  • Talibudeen, O. (1981) Cation exchange in soils: in The Chemistry of Soil Processes, D. J. Greenland and M. H. B. Hayes, eds., John Wiley & Sons, New York, 115–177.

    Google Scholar 

  • Talibudeen, O. and Goulding, K. W. T. (1983) Apparent charge heterogeneity in kaolins in relation to their 2:1 phyllosilicate content: Clays & Clay Minerals 31, 137–142.

    Google Scholar 

  • Teo, B.-K. (1986) EXAFS: Basic Principles and Data Analysis. Inorganic Chemistry Concepts 9, Springer-Verlag, Berlin, 349 pp.

    Google Scholar 

  • Teo, B.-K. and Joy, D.C., eds. (1981) EXAFS Spectroscopy, Plenum Press, New York, 275 pp.

  • Tewari, P. H., Campbell, A. B., and Lee, W. (1972) Adsorption of Co2+ by oxides from aqueous solution: Can. J. Chem. 50, 1642–1648.

    Google Scholar 

  • Tewari, P. H. and Lee, W. (1975) Adsorption of Co(II) at the oxide-water interface. J. Colloid Interface Sci. 52, 77–88.

    Google Scholar 

  • Tewari, P. H. and Mclntyre, N. S. (1975) Characterization of adsorbed Co(II) at the oxide-water interface: AICHE Symposium Series 71(150), 134–137.

    Google Scholar 

  • van Olphen, H. (1977) In Introduction to Clay Colloid Chemistry, 2nd ed.: Wiley-Interscience, New York, 301 pp.

  • Waychunas, G. A. and Brown Jr., G. E. (1990) Polarized X-ray absorption spectroscopy of metal ions in minerals: Identification of near-edge electronic transitions and scattering resonances and application to site geometry determinations: Phys. Chem. Minerals 17, 420–430.

    Google Scholar 

  • Waychunas, G. A., Brown Jr., G. E., and Apted, M. A. (1983) X-ray K-edge absorption spectra of Fe minerals and model compounds: Near-edge structure: Phys. Chem. Minerals 9, 212–215.

    Google Scholar 

  • Wieland, E. and Stumm, W. (1992) Dissolution kinetics of kaolinite in acidic aqueous solutions at 25°C: Geochim. Cosmochim. Acta 56, 3339–3355.

    Google Scholar 

  • Winick, H. and Doniach, S., eds. (1980) Synchrotron Radiation Research: Plenum Press, New York, 680 pp.

    Google Scholar 

  • Xie, Z. and Walther, J. V. (1992) Incongruent dissolution and surface area of kaolinite: Geochim. Cosmochim. Acta 56, 3357–3363.

    Google Scholar 

  • Young, R. A. and Hewat, A. W. (1988) Verification of the triclinic crystal structure of kaolinite: Clays & Clay Minerals 36, 225–232.

    Google Scholar 

  • Zachara, J. M., Cowan, C. E., Schmidt, R. L., and Ainsworth, C. C. (1988) Chromate adsorption by kaolinite: Clays & Clay Minerals 36, 317–326.

    Google Scholar 

  • Zachara, J. M., Resch, C. T., and Smith, S. C. (1994) Influence of humic substances on Co2+ sorption by a subsurface mineral separate and its mineralogical components: Geochim. Cosmochim. Acta 58, 553–566.

    Google Scholar 

Download references

Author information

Author notes

  1. Peggy A. O’Day

    Present address: Present address: Department of Geology and Geophysics, University of California, Berkeley, California, 94720, USA

Authors and Affiliations

  1. Surface and Aqueous Geochemistry Group, School of Earth Sciences, Stanford University, Stanford, California, 94305, USA

    Peggy A. O’Day, George A. Parks & Gordon E. Brown Jr.

Authors
  1. Peggy A. O’Day
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. George A. Parks
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Gordon E. Brown Jr.
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

O’Day, P.A., Parks, G.A. & Brown, G.E. Molecular Structure and Binding Sites of Cobalt(II) Surface Complexes on Kaolinite from X-Ray Absorption Spectroscopy. Clays Clay Miner. 42, 337–355 (1994). https://doi.org/10.1346/CCMN.1994.0420312

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1346/CCMN.1994.0420312

Key Words

Search

Navigation