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Iron Oxide-Clay Mineral Association in Brazilian Oxisols: A Magnetic Separation Study

Published online by Cambridge University Press:  28 February 2024

Mauricio Paulo Ferreira Fontes
Mauricio Paulo Ferreira Fontes*
Affiliation:
Departamento de Solos, Universidade Federal De Viçosa, 36570 Viçosa, MG, Brasil
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Abstract

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Selected Brazilian Oxisols were sampled and submitted to high-gradient magnetic separation (HGMS) to study the iron oxide-clay mineral associations. The soils, derived from four different parent materials, have mineralogy dominated mostly by hematite, goethite, and kaolinite. Gibbsite appears in most soil samples. The high-gradient magnetic separation showed good separation for some soils, as indicated by color differentiation and iron oxide segregation between magnetic and nonmagnetic fractions. Soils that showed a somewhat low surface area for the iron oxides associated with high phosphate adsorption were poorly separated by HGMS. This suggests a strong interaction between kaolinite and iron oxides, which would indicate a low estimation of their surface areas obtained by the difference method using BET-N2 data. A relative concentration of anatase and rutile in the magnetic portion of some of the samples was attributed to the presence of Fe, either as coatings on the crystals or within the structure of these two minerals.

Keywords

BrazilGoethiteHematiteMagnetic separationOxisols
Type
Research Article
Information
Clays and Clay Minerals , Volume 40 , Issue 2 , April 1992 , pp. 175 - 179
Copyright
Copyright © 1992, The Clay Minerals Society

References

Anderson, J. U., An improved pretreatment for mineralogical analysis of samples containing organic matter Clays & Clay Minerals 1963 10 380 – 388 10.1346/CCMN.1961.0100134.CrossRefGoogle Scholar
Coffin, D. E., A method for the determination of free iron in soils and clays Can. J. Soil Sci. 1963 43 9 – 17 10.4141/cjss63-002.CrossRefGoogle Scholar
Fontes, M P F and Weed, S. B., Iron oxides in Brazilian Oxisols: I. Mineralogy Soil Sci. Soc. Am. J. 1991 55 1143 – 1149 10.2136/sssaj1991.03615995005500040040x.CrossRefGoogle Scholar
Ghabru, S. K., St. Arnaud, R. J. and Mermut, A. R., Use of gradient magnetic separation in detailed clay mineral studies Can. J. Soil Sci. 1988 68 646 – 655 10.4141/cjss88-062.CrossRefGoogle Scholar
Golden, D. C. and Dixon, J. B., Silicate and phosphate influence in kaolin-iron oxide interactions Soil Sci. Soc. Am. J. 1985 43 802 – 808 10.2136/sssaj1979.03615995004300040038x.CrossRefGoogle Scholar
Greenland, D. J., Charge characteristics of some ka-olinite-iron hydroxide complexes Clay Miner. 1975 10 407 – 416.Google Scholar
Greenland, D. J. and Oades, J. M., Iron hydroxides and clay surfaces 9th Int. Cong. Soil Sci., Adelaide Australia 1968 I 657 – 668.Google Scholar
Hughes, J. C., High gradient magnetic separation of clays from Nigeria, Brazil and Colombia. I. The interrelationships of iron and aluminum extracted by acid ammonium oxalate and carbon J. Soil Sci. 1982 33 509 – 519 10.1111/j.1365-2389.1982.tb01785.x.CrossRefGoogle Scholar
Hughes, J. C. and Le Mare, P. H., High gradient magnetic separation of clays from Nigeria, Brazil and Colombia. II. Adsorption characteristics, the interrelationships with iron, aluminum, and carbon, and comparison with whole soil data J. Soil Sci. 1982 33 521 – 533 10.1111/j.1365-2389.1982.tb01786.x.CrossRefGoogle Scholar
Iannicelli, J., High extraction magnetic filtration of clay Clays & Clay Minerals 1976 24 64 – 68 10.1346/CCMN.1976.0240203.CrossRefGoogle Scholar
Jackson, M. L., Soil Chemical Analysis, Advanced Course 1979 2nd Madison Publ. by the author, Dept. Soil Sci., Univ. of Wisconsin.Google Scholar
Russell, J. D., Birnie, A. and Fraser, A. R., High gradient magnetic separation (HGMS) in soil clay studies Clay Miner. 1984 19 771 – 778 10.1180/claymin.1984.019.5.07.CrossRefGoogle Scholar
Schulze, D. G. and Dixon, J. B., High gradient magnetic separation of iron oxides and other magnetic minerals from soil clays Soil Sci. Soc. Am. J. 1979 43 793 – 799 10.2136/sssaj1979.03615995004300040036x.CrossRefGoogle Scholar
Schwertmann, U., Occurrence and formation of iron oxides in various pedoenvironments Iron in Soil and Clay Minerals NATO ASI Series C 1988 217 267 – 300 10.1007/978-94-009-4007-9_11.CrossRefGoogle Scholar
Weast, R. C., Handbook of Chemistry and Physics 1975 Cleveland, Ohio Chemical Rubber Co..Google Scholar
Weed, S. B. and Bowen, L. H., High gradient magnetic concentration of chlorite and hydroxy-interlayered minerals in soil clays Soil Sci. Soc. Am. J. 1990 54 274 – 280 10.2136/sssaj1990.03615995005400010044x.CrossRefGoogle Scholar