Abstract
0.5 molal iron(III) chloride solutions were hydrolysed at room temperature by base additions in the range OH/Fe mole ratio 0–2.75. After an ageing period the hydrolysed solutions were used to produce amorphous hydroxide gels from which crystalline products were grown at 65°C, at low pH or high pH. Examination of crystal composition and morphology and comparison with similarly treated nitrate solutions showed that the nucleation of hematite and goethite is inhibited in chloride containing solutions, which allow growth of small rod shaped β-FeOOH to predominate or occur exclusively in gels at pH 1–2. The addition of seed crystals of hematite and goethite allows competitive growth of all three minerals. The transformations β-FeOOH → α-Fe2O3 and β-FeOOH → α-FeOOH at pH 1–2 proceed by dissolution and reprecipitation and are promoted by adding seed crystals.
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Atkinson, R. J., Posner, A. M. and Quirk, J. P. (1968) Crystal nucleation in Fe(III) solutions and hydroxide gels: J. Inorg. Nucl. Chem. 30, 2371–2381. (Note: Legends to plates should read: Electron micrographs of goethite. Magnification × 40,000).
Atkinson, R. J., Posner, A. M. and Quirk, J. P. (1972) Kinetics of isotopic exchange of phosphate at the α-FeOOH–aqueous electrolyte interface: J. Inorg. Nucl. Chem. 34, 2201–2211.
Christensen, A. N. (1968) Hydrothermal preparation of goethite and hematite from amorphous iron(III) hydroxide: Acta Chem. Scand. 22, 1487–1490.
Collepardi, M., Massidda, L. and Rossi, G. (1972) Ageing of iron oxide gels: Trans. Instn. Mining Metall. (Sect. C. Mineral Process. Extr. Metall.) 81, C43–C46.
Collepardi, M., Massidda, L. and Rossi, G. (1973) Effect of pH and salt additions on ageing of ferric iron oxide gels: Trans. Instn. Mining Metall. (Sect. C. Mineral Process. Extr. Metall.) 82, C88–C91.
Cornell, R. M., Posner, A. M. and Quirk, J. P. (1974a) Crystal morphology and the dissolution of goethite: J. Inorg. Nucl. Chem. 36, 1937–1946.
Cornell, R. M., Posner, A. M. and Quirk, J. P. (1974b) The dissolution of synthetic goethites: the early stage: Soil Sci. Soc. Proc. 38, 377–378.
Feitknecht, W. and Michaelis, W. (1962) Ueber die Hydrolyse von Eisen(III)-perchlorat-Loesungen: Helv. Chim. Acta. 45, 212–224.
Fischer, W. R. and Schwertmann, U. (1975) The formation of hematite from amorphous iron(III) hydroxide: Clays & Clay Minerals 23, 33–37.
Fordham, A. W. (1970) Sorption and precipitation of iron on kaolinite III. The solubility of iron(III) hydroxides precipitated in the presence of kaolinite: Aust. J. Soil. Res. 8, 107–122.
Gallagher, K. J. (1970) The atomic structure of tubular subcrystals of β-Iron(III) oxide hydroxide: Nature 226, 1225–1228.
Haigh, C. J. (1967) The hydrolysis of iron in acid solutions: Proc. Aust. Inst. Mining and Metallurgy 223, 49–56.
Hsu, Pa Ho (1973) Appearance and stability of hydrolysed Fe(ClO4)3 solutions: Clays & Clay Minerals 21, 267–277.
Knight, R. J. and Sylva, R. N. (1974) Precipitation in hydrolysed iron(III) solutions: J. Inorg. Nucl. Chem. 36, 591–597.
Mackay, A. L. (1960) β-Ferric oxyhydroxide: Mineralog. Mag. 32, 545–557.
Mackenzie, R. C. and Meldau, R. (1959) The ageing of sesquioxide gels I. Iron oxide gels: Mineralog. Mag. 32, 153–165.
Murphy, P. J., Posner, A. M. and Quirk, J. P. (1975) Chemistry of iron in soils. Ferric hydrolysis products: Aust. J. Soil Res. 13, 189–201.
Robins, R. G. (1967) Hydrothermal precipitation in solutions of thorium nitrate, ferric nitrate and aluminium nitrate: J. Inorg. Nucl. Chem. 29, 431–435.
Schwertmann, U. and Fischer, W. R. (1966) Zur Bildung von α-FeOOH und α-Fe2O3 aus amorphem Eisen(III)-hydroxid: Z. Anorg. Allgem. Chem. 346, 137–142.
Soderquist, R. and Jansson, S. (1966) On an X-ray and electron microscope study of precipitates formed by the hydrolyses of iron(III) in 0.5 M NaCl ionic medium: Acta Chem. Scand. 20, 1417–1418.
Sylva, R. N. (1972) The hydrolysis of iron(III): Rev. Pure Appl. Chem. 22, 115–132.
Wefers, K. (1966a) Zum System Fe2O3–H2O. 1. Teil: Ber. Dtsch. Keram. Ges. 43, 677–684.
Wefers, K. (1966b) Zum System Fe2O3–H2O. 2. Teil: Ber. Dtsch. Keram. Ges. 43, 703–708.
Wolf, R. H. H., Wrischer, M. and Sipalo-Zuljevic, J. (1967) Electron-microscope investigation of the formation of colloidal beta FeOOH during slow hydrolysis of an aqueous ferric chloride solution at room temperature: Kolloid-Zeit. u. Zeit Polymere 215, 57–60.
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Atkinson, R.J., Posner, A.M. & Quirk, J.P. Crystal Nucleation and Growth in Hydrolysing Iron(III) Chloride Solutions. Clays Clay Miner. 25, 49–56 (1977). https://doi.org/10.1346/CCMN.1977.0250108
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DOI: https://doi.org/10.1346/CCMN.1977.0250108