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Identification of Noncrystalline (Fe,Cr)(Oh)3 by Infrared Spectroscopy

Published online by Cambridge University Press:  02 April 2024

James E. Amonette  and
Dhanpat Rai
James E. Amonette
Affiliation:
Department of Environmental Sciences, Battelle, Pacific Northwest Laboratories, P.O. Box 999, Richland, Washington 99352
Dhanpat Rai
Affiliation:
Department of Environmental Sciences, Battelle, Pacific Northwest Laboratories, P.O. Box 999, Richland, Washington 99352
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Abstract

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Iron-chromium hydroxides are important solid phases governing the aqueous concentrations of Cr(III) in soils and fly ashes. Although direct identification of noncrystalline (Fe,Cr)(OH)3 is difficult, the infrared spectra of noncrystalline Fe(OH)3 and Cr(OH)3, coprecipitated (Fe,Cr)(OH)3, and physical mixtures of Fe(OH)3 and Cr(OH)3 can be distinguished on the basis of the asymmetric stretching doublet (v3) of structural carbonate anions. As the Cr mole fraction of the coprecipitated (Fe,Cr)(OH)3 increases, the position of the low-frequency v3 peak (v3″) changes progressively to higher frequencies, and the carbonate v3 splitting decreases. No change in carbonate v3 splitting or v3″ location was observed for physical mixtures of Fe(OH)3 and Cr(OH)3. The changes in v3 splitting are believed to be caused by different degrees of polarization of the carbonate ligand by the Fe and Cr cations.

Pure Cr(OH)3 exhibits a strong affinity for carbonate and H2O and tends to remain noncrystalline even at very high pHs. In contrast, pure Fe(OH)3 gradually converts to crystalline goethite at high pH, to the exclusion of much of the H2O and carbonate. The presence of Cr in (Fe,Cr)(OH)3 solid solutions seems to inhibit the transformation to crystalline goethite. The strong association of carbonate with Cr and the kinetic inertness of Cr(III) inner-sphere complexes in general may account for the maintenance of noncrystalline solid-solution materials in lieu of transformation to a crystalline end product.

Keywords

Chromium hydroxideGoethiteInfrared spectroscopyIron hydroxideNoncrystallineSolid solution
Type
Research Article
Information
Clays and Clay Minerals , Volume 38 , Issue 2 , April 1990 , pp. 129 - 136
Copyright
Copyright © 1990, The Clay Minerals Society

References

References Cited

Brintzinger, H. and Hester, R. E., 1966 Vibrational analysis of some oxyanion-metal complexes Inorg. Chem. 5 980 – 985.CrossRefGoogle Scholar
Cotton, F. A. and Wilkinson, G., 1972 Advanced Inorganic Chemistry: A Comprehensive Text New York Wiley.Google Scholar
Dvorak, V., Feitknecht, W. and Georges, P., 1969 Sur les carbonates basiques de fer(III): I. Carbonate basique de fer(III) amorphe Heb. Chim. Acta 52 501 – 515.CrossRefGoogle Scholar
Fujita, J., Martell, A. E. and Nakamoto, K., 1962 Infrared spectra of metal chelate compounds—VIII. Infrared spectra of Co(III) carbonato complexes J. Chem. Phys. 36 339 – 345.CrossRefGoogle Scholar
Gatehouse, B. M., Livingstone, S. E. and Nyholm, R. S., 1958 The infrared spectra of some simple and complex carbonates J. Chem. Soc. 1958 3137 – 3142.CrossRefGoogle Scholar
Griffiths, P. R. and Dehaseth, J. A., 1986 Fourier Transform Infrared Spectrometry New York Wiley.Google Scholar
Grigor’ev, Y. M., Pozdnyakov, D. V. and Filimonov, V. N., 1972 Form of carbon dioxide chemisorption on metal oxides studied by infrared spectroscopic method Zh. Fiz. Khim. 46 316 – 320.Google Scholar
Harrison, J. B. and Berkheiser, V. E., 1982 Anion interactions with freshly prepared hydrous iron oxides Clays & Clay Minerals 30 97 – 102.CrossRefGoogle Scholar
Huffman, E. W. D., 1977 Performance of a new automatic carbon dioxide coulometer Microchem. J. 22 567 – 573.CrossRefGoogle Scholar
Lim-Nunez, R., Gilkes, R. J., Schultz, L. G., van Olphen, H. and Mumpton, F. A., 1985 Acid dissolution of synthetic metal-containing goethites and hematites Proc. Int. Clay Conf. Denver, 1985 Indiana The Clay Minerals Society, Bloomington 197 – 204.Google Scholar
Little, L. H., 1966 Infrared Spectra of Adsorbed Species London Academic Press.Google Scholar
Nakamoto, K., 1970 Infrared Spectra of Inorganic and Coordination Compounds New York Wiley.Google Scholar
Nakamoto, K., Fujita, J., Tanaka, S. and Kobayashi, M., 1957 Infrared spectra of metallic complexes—IV. Comparison of the infrared spectra of unidentate and bidentate metallic complexes J. Amer. Chem. Soc. 79 4904 – 4908.CrossRefGoogle Scholar
Rai, Dhanpat, Zachara, J. M., Eary, L. E., Ainsworth, C. C., Amonette, J. E., Cowan, C. E., Szelmeczka, R. W., Resch, C. T., Schmidt, R. L. and Girvin, D. C., (1988) Chromium reactions in geologic materials: Electric Power Research Institute, Palo Alto, California, Rept. EA5741, 280 pp.Google Scholar
Russell, J. D., Paterson, E., Fraser, A. R. and Farmer, V. C., 1975 Adsorption of carbon dioxide on goethite (alpha-FeOOH) surfaces, and its implications for anion adsorption J. Chem. Soc. Faraday Trans. I 71 1623 – 1630.CrossRefGoogle Scholar
Sass, B. M. and Rai, D., 1987 Solubility of amorphous chromium(III)-iron(III) hydroxide solid solutions. Inorg. Chem. 26 2228 – 2232.CrossRefGoogle Scholar
Serna, C. J., White, J. L. and Hem, S. L., 1978 Nature of amorphous aluminum hydroxycarbonate J. Pharm. Sci. 67 1144 – 1147.CrossRefGoogle ScholarPubMed