Molecular Characteristics of Phosphoric Acid Treated Soils

Authors: Amin Eisazadeh, Khairul Anuar Kassim, Hadi Nur

Abstract:

The expansive nature of soils containing high amounts of clay minerals can be altered through chemical stabilization, resulting in a material suitable for construction purposes. The primary objective of this investigation was to study the changes induced in the molecular structure of phosphoric acid stabilized bentonite and lateritic soil using Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FTIR) spectroscopy. Based on the obtained data, it was found that a surface alteration mechanism was the main reason responsible for the improvement of treated soils. Furthermore, the results indicated that the Al present in the octahedral layer of clay minerals were more amenable to chemical attacks and also partly responsible for the formation of new products.

Keywords: Bentonite, Laterite clay, Molecularcharacterization, Phosphoric acid, Stabilization

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1328017

References:

[1] O. G. Ingles and J. B. Metcalf, Soil stabilization - principles and practice, Melbourne: Butterworth, 1972.
[2] J. W. Lyons and G. J. McEwan, "Phosphoric acid in soil stabilization, part I. Effect on engineering properties of soils," Highway Research Board Bulletin 318, Washington, D.C., 1962, pp. 4-14.
[3] J. Sutton and E. McAlexander, "Soil improvement committee - Admixture report," Geotechnical Special Publication No. 12, New York: ASCE, 1987, pp. 123-124.
[4] J. Medina and H. N. Guida, "Stabilization of Lateritic soils with phosphoric acid," Journal of Geotechnical and Geological Engineering, vol. 13, 1995, pp. 199-216.
[5] H. F. Winterkorn, "Introductory remarks," Highway Research Board Bulletin 318, Washington, D.C., 1962, pp. 1-3.
[6] M. L. McKelvy, T. R. Britt, B. L. Davis, J. K. Gillie, L. A. Lentz, A. Leugers, R. A. Nyquist, and C. L. Putzig, "Infrared Spectroscopy," Analytical Chemistry, vol. 68, 1996, pp. 93-160.
[7] B. Stuart, Modern Infrared Spectroscopy, New York and UK: John Wiley & Sons, 1996.
[8] V. C. Farmer, The Infrared Spectra of Minerals, London: Mineralogical Society, 1974.
[9] R. A. Kinsey, R. J. Kirkpatrick, J. Hower, K. A. Smith, and E. Oldfield, "High resolution aluminum-27 and silicon-29 nuclear magnetic resonance spectroscopic study of layer silicates, including clay minerals," American Mineralogist, vol. 70, 1985, pp. 537-548.
[10] G. Engelhardt and D. Michel, High resolution solid state NMR of silicates and zeolites, UK: John Wiley & Sons, 1987.
[11] P. F. Barron, P. Slade, and R. L. Frost, "Solid-state silicon-29 spinlattice relaxation in several 2:1 phyllosilicate minerals," Journal of Physical Chemistry, vol. 89, 1985, pp. 3305-3310.
[12] C. P. Herrero, J. Sanz, and J. M. Serratosa, "Tetrahedral cation ordering in layer silicates by 29Si NMR spectroscopy," Solid State Communications, vol. 53, 1985, pp. 151-154.
[13] C. A. J. Weiss, S. P. Altaner, and R. J. Kirkpatrick, "High-resolution 29Si NMR spectroscopy of 2:1 layer silicates: Correlations among chemical shift, structural distortions, and chemical variations," American Mineralogist, vol. 72, 1987, pp. 935-942.
[14] BSI, "British Standard methods of test for soils for civil engineering purposes: Part 4, Compaction-related tests," BS1377. London: British Standards Institution, 1990.
[15] BSI, "Stabilized materials for civil engineering purposes: Part 2, Methods of test for cement-stabilized and lime-stabilized materials," BS1924. London: British Standards Institution, 1990.
[16] J. Madejova and P. Komadel, "Baseline studies of the clay minerals society source clays: Infrared methods," Clays and Clay Minerals, vol. 49, no. 5, 2001, pp. 410-432.
[17] H. W. V. D. Marel and H. Beutelspacher, Atlas of infrared spectroscopy of clay minerals and their admixtures, Amsterdam: Elsevier Scientific Publishing Company, 1976.
[18] K. Nacamoto, Infrared spectra of inorganic and coordinated compounds, New York: John Wiley & Sons, 1970.