Hostname: page-component-848d4c4894-x5gtn Total loading time: 0 Render date: 2024-05-01T07:12:42.119Z Has data issue: false hasContentIssue false
  • English
  • Français

Comparison of Techniques for Determining the Fractal Dimensions of Clay Minerals

Published online by Cambridge University Press:  28 February 2024

Kalumbu Malekani ,
James A. Rice  and
Jar-Shyong Lin
Kalumbu Malekani
Affiliation:
Department of Chemistry and Biochemistry, South Dakota State University, Brookings, South Dakota 57007
James A. Rice
Affiliation:
Department of Chemistry and Biochemistry, South Dakota State University, Brookings, South Dakota 57007
Jar-Shyong Lin
Affiliation:
Center for Small-Angle Scattering, Solid-State Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
Get access Rights & Permissions [Opens in a new window]

Abstract

Small-angle X-ray scattering (SAXS), adsorption and nuclear magnetic resonance (NMR) techniques were used to determine the fractal dimensions (D) of 3 natural reference clays: 1) a kaolinite (KGa-2); 2) a hectorite (SHCa-1), and 3) a Ca-montmorillonite (STx-1). The surfaces of these clays were found to be fractal with D values close to 2.0. This is consistent with the common description of clay mineral surfaces as smooth and planar. Some surface irregularities were observed for hectorite and Ca-montmorillonite as a result of impurities in the materials. The SAXS method generated comparable D values for KGa-2 and STx-1. These results are supported by scanning electron microscopy (SEM). The SAXS and adsorption methods were found to probe the surface irregularities of the clays while the nuclear magnetic resonance (NMR) technique seems to reflect the mass distribution of certain sites in the material. Since the surface nature of clays is responsible for their reactivity in natural systems, SAXS and adsorption techniques would be the methods of choice for their fractal characterization. Due to its wider applicable characterization size-range, the SAXS method appears to be better suited for the determination of the fractal dimensions of clay minerals.

Keywords

AdsorptionClayFractalNMRSmall-angle x-ray scattering
Type
Research Article
Information
Clays and Clay Minerals , Volume 44 , Issue 5 , October 1996 , pp. 677 - 685
Copyright
Copyright © 1996, The Clay Minerals Society

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

Avnir, D.. 1986. Fractal aspects of surface science: an interim report. Mat Res Soc Symp Proc 73: 321–329.CrossRefGoogle Scholar
Avnir, D., Farin, D. and Pfeifer, P.. 1983. Chemistry in noninteger dimensions between two and three. II. Fractal surfaces of adsorbents. J Chem Phys 70: 3566–3571.CrossRefGoogle Scholar
Avnir, D., Farin, D. and Pfeifer, P.. 1984. Molecular fractal surfaces. Nature 308: 261–263.CrossRefGoogle Scholar
Ben Ohoud, M., Obrecht, F. and Gatineau, L.. 1988. Surface area, mass fractal dimension, and apparent density of powders. J Coll Interface Sci 124: 156–161.CrossRefGoogle Scholar
Bottero, J.Y., Tchoubar, D., Axelos, M.A.V., Quienne, P. and Fiessinger, F.. 1990. Flocculation of silica colloids with hydroxy aluminum polycations. Relation between floc structure and aggregation mechanisms. Langmuir 6: 596–602.CrossRefGoogle Scholar
Braker, W. and Mossman, A.L.. 1971. Matheson gas data book, Matheson Gas Products: East Rutherford, NJ. 574 p.Google Scholar
Collins, M.J., Bishop, A.N. and Farrimond, P.. 1995. Sorption by mineral surfaces: Rebirth of the classical condensation pathway for kerogen formation? Geochim Cosmochim Acta 59: 2387–2391.CrossRefGoogle Scholar
Devreux, F., Boilot, J.P., Chaput, F. and Sapoval, B.. 1990. NMR determination of the fractal dimension in silica aerogels. Phys Rev Lett 65: 614–617.CrossRefGoogle ScholarPubMed
Farin, D. and Avnir, D.. 1989. The fractal nature of molecule-surface interactions and reactions. In: Avnir, D., editor. The fractal approach to heterogeneous chemistry. Chichester, England: Wiley. p 271–293.Google Scholar
Gregg, S.J. and Sing, K.S.W.. 1982. Adsorption, surface area, and porosity. London: Academic Press. 371 p.Google Scholar
Keefer, K.D. and Schaefer, D.W.. 1986. Growth of fractally rough colloids. Phys Rev Lett 56: 2376–2379.CrossRefGoogle ScholarPubMed
Keil, R.G., Tsamaskis, E., Fuh, C.B., Giddings, J.C. and Hedges, J.I.. 1994. Mineralogical and textural controls on the organic composition of coastal marine sediments: Hydrodynamic separation using SPLITT-fractionation. Geochim Cosmochim Acta 58: 879–893.CrossRefGoogle Scholar
Malekani, K. and Rice, J.A.. 1995. unpublished research. Department of Chemistry and Biochemistry, South Dakota State University, Brookings, SD 57007.Google Scholar
Mayer, L.M.. 1994. Surface area control of organic carbon accumulation in continental shelf sediments. Geochim Cosmochim Acta 58: 1271–1284.CrossRefGoogle Scholar
McClellan, A.L. and Harnsberger, H.F.. 1967. Cross sectional area of molecules adsorbed on solid surfaces. J Coll Interface Sci 23: 577–599.CrossRefGoogle Scholar
Murphy, E.M., Zachara, J.M., Smith, S.C., Phillips, J.L. and Wietsma, T.W.. 1994. Interaction of hydrophobic organic compounds with mineral-bound humic substances. Environ Sci Technol 28: 1291–1299.CrossRefGoogle ScholarPubMed
Ochs, M., Cosovic, B. and Stumm, W.. 1994. Coordinative and hydrophobic interactions of humic substances with hydrophilic Al2O3 and hydrophobic mercury surfaces. Geochim Cosmochim Acta 58: 639–650.CrossRefGoogle Scholar
Pfeifer, P. and Avnir, D.. 1983. Chemistry in noninteger dimensions between two and three: I. Fractal theory of heterogeneous surfaces. J Chem Phys 79: 3558–3565.CrossRefGoogle Scholar
Reich, M.H., Russo, S.P., Snook, I.K. and Wagenfeld, H.K.. 1990. The application of SAXS to determine the fractal properties of porous carbon-based materials. J Coll Interface Sci 135: 353–362.CrossRefGoogle Scholar
Rojanski, D., Huppert, D., Bale, H.D., Dacai, X., Schmidt, P.W., Farin, D., Seri-Levy, A. and Avnir, D.. 1986. Integrated fractal analysis of silica: adsorption, electronic energy transfer, and small-angle x-ray scattering. Phys Rev Lett 56: 2505–2508.CrossRefGoogle ScholarPubMed
Russell, T.P., Lin, J.S. and Spooner, S.. 1988. Intercalibration of small-angle and neutron scattering data. J Appl Crystalog 21: 629–638.CrossRefGoogle Scholar
Schaefer, D.W.. 1989. Polymers, fractals, and ceramic materials. Science 243: 1023–1027.CrossRefGoogle ScholarPubMed
Schaefer, D.W. and Martin, J.E.. 1984. Fractal geometry of colloidal aggregates. Phys Rev Lett 52: 2371–2374.CrossRefGoogle Scholar
Schmidt, P.W.. 1989. Use of scattering to determine the fractal dimension. In: Avnir, D., editor. The fractal approach to heterogeneous chemistry. Chichester, England: Wiley. p 67–79.Google Scholar
Sokolowska, Z., Stawinski, J., Patrykiejew, A. and Sokolowska, S.. 1989. A note on fractal analysis of adsorption process by soils and soil minerals. Internat Agrophys 5: 1–23.Google Scholar
Theng, B.K.G.. 1974. The chemistry of clay-organic reactions. New York: Wiley. 362 p.Google Scholar
van Damme, H. and Fripiat, J.J.. 1985. A fractal analysis of adsorption processes by pillared swelling clays. J Chem Phys 82: 2785–2789.CrossRefGoogle Scholar
van Damme, H., Levitz, P., Bergaya, F., Alcover, J.F., Gatineau, L. and Fripiat, J.J.. 1986. Monolayer adsorption on fractal surfaces: A simple two-dimensional simulation. J Chem Phys 85: 616–625.CrossRefGoogle Scholar
van Olphen, H.. 1963. An introduction to clay colloid chemistry. New York: John Wiley. 346 p.Google Scholar
van Olphen, H. and Fripiat, J.J.. 1979. Data handbook for clay materials and non-metallic minerals. Oxford: Pergamon. 301 p.Google Scholar
White, G.N., Dixon, J.B., Weaver, R.M. and Kunkle, A.C.. 1991. Genesis and morphology of iron sulfides in gray kaolins. Clays Clay Miner 39: 70–76.CrossRefGoogle Scholar
Wignall, G.D., Lin, J.S. and Spooner, S.. 1990. The reduction of parasitic scattering in small-angle x-ray scattering by three pinhole collimating system. J Appl Crystall 23: 241–246.CrossRefGoogle Scholar