Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-10T08:22:17.305Z Has data issue: false hasContentIssue false
  • English
  • Français

Inhibition of Sintering by Si During the Conversion of Si-Rich Ferrihydrite to Hematite

Published online by Cambridge University Press:  28 February 2024

Susan M. Glasauer ,
Paul Hug ,
Peter G. Weidler  and
Andreas U. Gehring
Susan M. Glasauer
Affiliation:
Lehrstuhl für Bodenkunde, Technische Universität München, 85350 Freising-Weihenstephan, Germany
Paul Hug
Affiliation:
Institut für Anorganische Chemie, Universität Zürich, CH-8057 Zürich, Switzerland
Peter G. Weidler
Affiliation:
Institut für Terrestrische Ökologie, ETH Zürich, CH-8952 Schlieren, Switzerland
Andreas U. Gehring
Affiliation:
Institut für Terrestrische Ökologie, ETH Zürich, CH-8952 Schlieren, Switzerland
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The distribution and chemical state of Si in a synthetic 2-line ferrihydrite with a Si/(Si + Fe) molar ratio of 0.11 was studied. Heat treatment under oxidizing conditions shows that Si-rich ferrihydrite is stable to 400°C. The transformation to hematite and the formation of a polymerized amorphous-silica phase occur at 850°C. At this temperature, the specific surface area decreases greatly and the average pore diameter increases, which is indicative of sintering. Heating under severe reducing conditions causes a segregation of Si from Fe and results in a mixture of elemental Fe and SiO2. Surface and structural data suggest that Si is located near the particle surface where it limits the rearrangement of Fe octahedra to form hematite.

Keywords

BETFerrihydriteSiSinteringXPS
Type
Research Article
Information
Clays and Clay Minerals , Volume 48 , Issue 1 , February 2000 , pp. 51 - 56
Copyright
Copyright © 2000, The Clay Minerals Society

References

Barrett, E.P. Joyner, L.G. and Halenda, P.P., 1951 The determination of pore volume and area distribution in porous substances. I. Computations from nitrogen isotherms. Journal of the American Chemical Society 73 373–380 10.1021/ja01145a126.CrossRefGoogle Scholar
Carlson, L. and Schwertmann, U., 1981 Natural ferrihydrites in surface deposits from Finland and their association with silica. Geochimica et Cosmochimica Acta 45 421–429 10.1016/0016-7037(81)90250-7.CrossRefGoogle Scholar
Childs, C.W. Kanasaki, N. and Yoshinaga, N., 1993 Effect of heating in air on Si- and Ge-containing ferrihydrites. Clay Science 9 65–80.Google Scholar
Farmer, V.C. and Farmer, V.C., 1974 The anhydrous oxide minerals The Infrared Spectra of Minerals, Mineralogical Society Monograph 4 London Mineralogical Society 183–204 10.1180/mono-4.10.CrossRefGoogle Scholar
Glasauer, S.M., 1995 Silicate associated with Fe(hydr)oxides .Google Scholar
Gregg, S.J. and Sing, K.S.W., 1982 Adsorption, Surface Area and Porosity. London Academic Press.Google Scholar
Herbillon, A. and Tran Vinh An, J., 1969 Heterogeneity in silicon-iron mixed hydroxides. Journal of Soil Science 20 223–235 10.1111/j.1365-2389.1969.tb01569.x.CrossRefGoogle Scholar
Hochella, M.E. and Hawthorne, F.C., 1988 Auger electron and X-ray photoelec-tron spectroscopies Spectroscopic Methods in Mineralogy and Geology, Reviews in Mineralogy, Volume 18 Washington, D.C. Mineralogical Society of America 573–637 10.1515/9781501508974-015.CrossRefGoogle Scholar
Kinniburgh, D.G. Milne, C.J. and Venema, P., 1995 Design and construction of a personal-computer-based automatic titrator. Soil Science Society of America Journal 59 417–422 10.2136/sssaj1995.03615995005900020021x.CrossRefGoogle Scholar
McIntyre, N.S. and Zetaruk, D.G., 1977 X-ray photoelectron spectroscopic studies of iron oxides. Analytical Chemistry 49 1521–1529 10.1021/ac50019a016.CrossRefGoogle Scholar
Moenke, H.H.W. and Farmer, V.C., 1974 Silica, the three-dimensional silicates, borosilicates and beryllium silicates The Infrared Spectra of Minerals, Mineralogical Society Monograph 4 London Mineralogical Society 365–382 10.1180/mono-4.16.CrossRefGoogle Scholar
Parfitt, R.L. Van der Gaast, S.J. and Childs, C.W., 1992 A structural model for natural siliceous ferrihydrite. Clays and Clay Minerals 40 675–681 10.1346/CCMN.1992.0400607.CrossRefGoogle Scholar
Paterson, E. Swaffield, R. and Wilson, M.J., 1994 X-ray photospectros-copy Clay Mineralogy: Spectroscopic and Chemical Determinative Methods London Chapman and Hall 226–259 10.1007/978-94-011-0727-3_6.CrossRefGoogle Scholar
Perkin-Elmer, , 1979 Handbook of X-ray Photoelectron Spec-trocopy. Minnesota Perkin-Elmer.Google Scholar
Schwertmann, U. and Fechter, H., 1982 The point of zero charge of natural and synthetic ferrihydrites and its relation to adsorbed silicate. Clay Minerals 17 471–476 10.1180/claymin.1982.017.4.10.CrossRefGoogle Scholar
Schwertmann, U. and Thalmann, H., 1976 The influence of Fe(II), Si and pH on the formation of lepidocrocite and ferrihydrite during oxidation of aqueous FeCl2 solutions. Clay Minerals 11 189–200 10.1180/claymin.1976.011.3.02.CrossRefGoogle Scholar
Seyama, H. and Soma, M., 1985 Bonding-state characterization of the constituents of silicate minerals by X-ray pho-toelectron spectroscopy. Journal of the Chemical Society, Faraday Transactions 1 81 485–495 10.1039/f19858100485.CrossRefGoogle Scholar
Sing, J.W. Everett, D.H. Haul, R.A.W. Moscou, L. Pierotti, R.A. Rouquerol, J. and Siemieniewska, T., 1985 Reporting physisorption data for gas/solid systems. Pure and Applied Chemistry 57 603–619 10.1351/pac198557040603.CrossRefGoogle Scholar
Soma, M. Seyama, H. Yoshinaga, N. Theng, B.K.G. and Childs, C.W., 1996 Bonding state of silicon in natural fer-rihydrites by X-ray photoelectron spectroscopy. Clay Science 9 385–391.Google Scholar
Stanjek, H. and Weidler, P.G., 1992 The effect of dry heating on the chemistry, surface area and oxalate solubility of synthetic 2-line and 6-line ferrihydrite. Clay Minerals 27 397–412 10.1180/claymin.1992.027.4.01.CrossRefGoogle Scholar
Vempati, R. K. Loeppert, R.H. Duffner, D.C. and Cocke, D.L., 1990 X-ray photoelectron spectroscopy as a tool to differentiate silicon-bonding state in amorphous iron oxides Soil Science Society of America Journal 54 695–698 10.2136/sssaj1990.03615995005400030010x.CrossRefGoogle Scholar
Weidler, P.G., 1997 BET sample preparation of synthetic ferrihydrite and its influence on the determination of surface area and porosity. Journal of Porous Materials 4 165–169 10.1023/A:1009610800182.CrossRefGoogle Scholar
Yoshinaga, N. and Kanasaki, N., 1993 Synthesis of ferrihydrite and feroxyhite. Clay Science 9 43–51.Google Scholar
Zhao, J. Huggins, F.E. Feng, Z. and Huffman, G.P., 1994 Ferrihydrite surface structure and its effect on phase transformation. Clays and Clay Minerals 42 737–746 10.1346/CCMN.1994.0420610.Google Scholar