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Effect of Time and Temperature on the Chemical Composition and Crystallization of Mixed Iron and Aluminum Species

Published online by Cambridge University Press:  28 February 2024

C. Colombo  and
A. Violante
C. Colombo
Affiliation:
Dipartimento di Scienze Chimico-Agrarie, Università di Napoli “Federico II,” 80055 Portici, Napoli, Italy
A. Violante
Affiliation:
Dipartimento di Scienze Chimico-Agrarie, Università di Napoli “Federico II,” 80055 Portici, Napoli, Italy
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Abstract

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We studied the influence of time ageing (up to 120 d at 50°C or 30d at 95°C) on the mineralogical and chemical composition of hydrolytic species of mixed aluminum and iron samples formed at pH 5.0 and initial Fe/Al molar ratio (Ri) ranging from 0.1 to 10. The partitioning distribution of Fe and Al in soluble or solid phases of different sizes (<0.01, 0.2–0.01, >0.2 μm) depended on Ri and time. The ratio of Fe to Al of the <0.2 μm Fe-Al species of the samples at Ri ≤ 4 slowly increased with time. Usually the higher Ri the higher the amount of Fe + Al present in soluble or very fine solids (<0.2 μm). With time, high percentages of Fe were found mainly in the <0.01 μm while the Al increase in the >0.2 μm sizes. Gibbsite, without the presence of well-crystallized Fe-oxides was formed in the samples at Ri ≤ 0.5 after 7–120 d at 50°C. In the samples at Ri ≥ 1 low-crystalline ferrihydrite was observed after ≥60 d. Only after 120 d did gibbsite or hematite start to form in the samples at Ri = 1–10. However, even after prolonged ageing at 95°C, low-crystalline ferrihydrite was still present at Ri ≤ 4.

The Fe-Al samples at Ri ≥ 1 aged 32 d at 50°C dissolved almost completely by acid ammonium-oxalate (82–93%), but the samples at Ri ≤ 0.5 were only partially solubilized (13–60%). After further 30 d at 95°C, the percentages of Fe + Al solubilized by oxalate from the samples at R ≥ 0.5 was still relatively high (22–39%).

Keywords

AluminumCrystallizationGibbsiteIron
Type
Research Article
Information
Clays and Clay Minerals , Volume 44 , Issue 1 , February 1996 , pp. 113 - 120
Copyright
Copyright © 1996, The Clay Minerals Society

References

Barrón, V., Rendon, J.L., Torrent, J. and Serna, C.J.. 1984. Relation of infrared, crystallochemical, and morphological properties of Al-substituted hematites. Clays & Clay Miner 32: 475–479.CrossRefGoogle Scholar
Cornell, R.M. and Schwertmann, U.. 1979. Influence of organic anions on the crystallization of ferrihydrite. Clays & Clay Miner 27: 402–410.CrossRefGoogle Scholar
Cornell, R.M., Giovanoli, R. and Schneider, W.. 1989. Review of the hydrolysis of iron (III) and crystallization of amorphous iron (III) hydroxide hydrate. J Chem Technol Biotechnol 46: 115–134.CrossRefGoogle Scholar
Gastuche, M.C., Bruggenwert, T. and Mortland, M.M.. 1964. Crystallization of mixed iron and aluminum gels. Soil Sci 98: 281–289.CrossRefGoogle Scholar
Goh, T.B., Huang, P.M., Dudas, M.J. and Pawluk, S.. 1987. Effect of iron on the nature of precipitation products of aluminum. Can J Soil Sci 67: 135–145.CrossRefGoogle Scholar
Hsu, P.H.. 1989. Aluminum hydroxides and oxyhydroxides. In: Dixon, J.B., Weed, S.R., editors. Minerals in Soils Environments. 2nd ed. Madison, Wisconsin: Soil Sci Soc Am 331–378.Google Scholar
Huang, P.M. and Violante, A.. 1986. Influence of organic acids on crystallization and surface properties of precipitation products of aluminum. In: Huang, P.M., Schnitzer, M., editors. Interaction of Soil Minerals with Natural Organics and Microbs. Soil Sci Soc Am Spec Pub 17: 549–592.Google Scholar
Krishnamurti, G.S.R., Violante, A. and Huang, P.M.. 1995. Influence of Fe on the stabilization of hydroxy-Al interlayers in mont-morillonite. In: Churchman, G.J., Fitzpatrick, R.W., Eggleton, R.A., editors. Clays Controlling the Environments. Proc 10th Int Clay Conf Adelaide, Australia. Melboume: CSIRO Publishing. 183–186.Google Scholar
Lewis, D.G. and Schwertmann, U.. 1979. The influence of aluminum on the formation of iron oxides. IV. The influence of [Al], [OH], and temperature. Clays & Clay Miner 27: 195–200.CrossRefGoogle Scholar
Mehra, O.P. and Jackson, M.L.. 1960. Iron oxide removal from soils and clays by dithionite-citrate systems buffered with sodium bicarbonate. Clays & Clay Miner 7: 317–327.CrossRefGoogle Scholar
Rengasamy, P. and Oades, J.M.. 1979. Interaction of monomeric and polymeric species of metal ions with clay surfaces. IV Mixed systems of aluminium (III) and iron (III). Aust J Soil Res 17: 141–153.CrossRefGoogle Scholar
Schulze, D.G. and Schwertmann, U.. 1984. The influence of aluminum on iron oxides: X The properties of Al-substituted goethite. Clay Mineral 19: 521–529.CrossRefGoogle Scholar
Schwertmann, U.. 1964. Differenzierung der Eisenoxide des Bodens durch photochemische Extraktion mit saurer Ammoniumoxalat-Lösung. Z Pflanzenernähr Bodenk 105: 194— 202.CrossRefGoogle Scholar
Schwertmann, U.. 1988. Some properties of soil and synthetic iron oxides. In: Stucki, J.W., Goodmann, B.A., Schwertmann, U., editors. Iron in Soils and Clay Minerals. Nato Advanced Institute. Dordrecht, Neth.: Reidel Publishing Company. Vol. 217: 203–205.CrossRefGoogle Scholar
Schwertmann, U., Fitzpatrick, R.W., Taylor, R.M. and Lewis, D.G.. 1979. The influence of aluminum on iron oxides. II. Preparation and properties of Al-substituted hematites. Clays & Clay Miner 27: 105–112.CrossRefGoogle Scholar
Schwertmann, U. and Taylor, R.M.. 1989. Iron oxides. In: Dixon, J.B., Weed, S.R., editors. Minerals in Soils Environments. 2nd ed. Madison, Wisconsin: Soil Sci Soc Am 379–439.Google Scholar
Schwertmann, U. and Cornell, R.M.. 1991. Iron Oxides in the Laboratory. Weinheim City, Germany: Weinheim: VCH. 89–94.Google Scholar
Taylor, R.M. and Schwertmann, U.. 1978. The influence of aluminum on iron oxides: Part I. The influence of Al on Fe oxide formation from the Fe(II) system. Clays & Clay Miner 26: 373–383.CrossRefGoogle Scholar
Torrent, J., Schwertmann, U. and Barrón, V.. 1987. The reductive dissolution of synthetic goethite and hematite in dithionite. Clay Mineral 22: 329–337.CrossRefGoogle Scholar