Clays and Clay Minerals

, Volume 43, Issue 2, pp 141–149 | Cite as

Retention of Cobalt by Pure and Foreign-Element Associated Goethites

  • Allan Bibak
  • Joachim Gerth
  • Ole K. Borggaard


Retention studies of the cobalt-goethite system were carried out using synthetic, star-shaped and lath-shaped pure, Al-, Cd-, Cu- and Si-associated goethites. Aluminium and Si are commonly occurring foreign elements in natural goethites. The goethites were prepared by coprecipitating Fe and the foreign element under controlled conditions and characterized by X-ray diffraction, transmission electron microscopy, specific surface area determination and 2 M HCl extraction. The foreign-element associated goethites contained ∼3, ∼5 and ∼9 mole % Al, ∼4 mole % Cd and ∼3 mole % Cu incorporated by isomorphous substitution but only ∼0.4 mole % of probably occluded Si. Crystal size and shape but also number of defects and domains, and hence specific surface area, unit-cell dimensions and reactivity towards 2 M HCl, exhibited great variability among the goethites. Accordingly the amounts of Co sorbed from initially 10−7 M Co in 0.1 M Ca(NO3)2 in relation to pH (3–8) and reaction time (2–504 h) were very different for the eight goethites. The affinity of Co is highest for Cd- and lowest for Cu-goethite. These samples also form the extremes regarding time-dependent sorption with Cu-goethite showing the smallest and Cd-goethite the largest increase in sorption with increasing reaction time. The Co uptake was not caused by precipitation Co(III) oxides due to Co(II) oxidation, since oxygen exclusion during sorption had no effect on the amount of Co sorbed. The amounts of sorbed Co extracted by 2 M HCl decreased with increasing sorption time but 40–87% of sorbed Co remained unextracted after 48 h, most in Cu-goethite and least in lath-shaped pure goethite. The strong retention suggests Co uptake by diffusion into micropores and fissures resulting from structural defects and intergrowths. The diffusion coefficients range from 3·10−19 to 6·10−17 cm2/s with the highest values for Al- and Si-associated goethites emphasizing the importance for Co immobilization, and hence availability, of foreign-element associations in goethite.

Key Words

Al-goethite Cd-goethite Co-extraction Co-sorption Cu-goethite Micropore diffusion Si-goethite 


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  1. Alloway, B. J. 1990. Heavy Metals in Soils. Glasgow: Blackie, 339 pp.Google Scholar
  2. Benjamin, M. M., and J. O. Leckie. 1981. Multiple-site adsorption of Cd, Cu, Zn, and Pb on amorphous iron oxyhydroxide. J. Colloid Interf. Sci. 79: 209–221.CrossRefGoogle Scholar
  3. Borggaard, O. K. 1990. Dissolution and Adsorption Properties of Soil Iron Oxides. Copenhagen: DSR-Forlag, 122 pp.Google Scholar
  4. Bruemmer, G.W., J. Gerth, and K. G. Tiller. 1988. Reaction kinetics of the adsorption and desorption of nickel, zinc and cadmium by goethite. I. Adsorption and diffusion of metals. J. Soil Sci. 39: 37–52.CrossRefGoogle Scholar
  5. Cornell, R. M., and R. Giovanoli. 1986. Factors that govern the formation of multi-domainic goethites. Clays & Clay Miner. 34: 557–564.CrossRefGoogle Scholar
  6. Cornell, R. M., R. Giovanoli, and P. W. Schindler. 1987. Effect of silicate species on the transformation of ferrihy-drite into goethite and hematite in alkaline media. Clays & Clay Miner. 35: 21–28.CrossRefGoogle Scholar
  7. Crank, J. 1975. The Mathematics of Diffusion, 2. Ed. Oxford: Clarendon Press, 11–27.Google Scholar
  8. Fordham, A., and K. Norrish. 1983. The nature of soil particles particularly those reacting with arsenate in a series of chemically treated samples. Aus. J. Soil Res. 31: 455–477.CrossRefGoogle Scholar
  9. Gerth, J. 1990. Unit-cell dimensions of pure and trace metal-associated goethites. Geochim. Cosmochim. Acta 54: 363–371.CrossRefGoogle Scholar
  10. Gerth, J., G.W. Brümmer, and K.G. Tiller. 1993. Retention of Ni, Zn and Cd by Si-associated goethite. Z. Pflanzenernähr. Bodenk. 156: 123–129.CrossRefGoogle Scholar
  11. Gillman, G. P. 1984. Using variable charge characteristics to understand the exchangeable cation status of oxic soils. Aust. J. Soil Res. 22: 71–80.CrossRefGoogle Scholar
  12. Kosmas, C. S., D. P. Franzmeier, and D. G. Schulze. 1986. Relationship among derivative spectroscopy, color, crystallite dimensions, and Al substitution of synthetic goethites and hematites. Clays & Clay Miner. 34: 625–634.CrossRefGoogle Scholar
  13. Kumar, R., R. K. Ray, and A. K. Biswas. 1990. Physico-chemical nature and leaching behaviour of goethites containing Ni, Co and Cu in the sorption and coprecipitation mode. Hydrometallurgy 25: 61–83.CrossRefGoogle Scholar
  14. Mann, S., R. M. Cornell, and U. Schwertmann. 1985. The influence of aluminium on iron oxides: XII. High-resolution transmission electron microscopic (HRTEM) study of aluminous goethites. Clay Miner. 20: 255–262.CrossRefGoogle Scholar
  15. Norrish, K., and R. M. Taylor. 1961. The isomorphous replacement of iron by aluminium in soil goethite. J. Soil Sci. 12: 294–306.CrossRefGoogle Scholar
  16. Padmanabham, M. 1983. Competitive study of the adsorp-tion-desorption behaviour of Cu(II), Zn(II), Co(II) and Pb(II) at the goethite-solution interface. Aust. J. Soil Res. 21: 515–525.CrossRefGoogle Scholar
  17. Quin, T. G., G. J. Long, C. G. Benson, S. Mann, and R. J. P. Williams. 1988. Influence of silicon and phosphorus on structural and magnetic properties of synthetic goethite and related oxides. Clays & Clay Miner. 36: 165–175.CrossRefGoogle Scholar
  18. Schenck, C. V., J. G. Dillard, and J. W. Murray. 1983. Surface analysis and sorption of Co(II) on goethite. J. Colloid Interf. Sci. 95: 398–409.CrossRefGoogle Scholar
  19. Schulze, D. G. 1984. The influence of aluminium on iron oxides. VIII. Unit-cell dimensions of Al-substituted goethites and estimation of Al from them. Clays & Clay Miner. 32: 36–44.CrossRefGoogle Scholar
  20. Schulze, D. G., and U. Schwertmann. 1984. The influence of Al on iron oxides. X. Properties of Al-substituted goethites. Clay Miner. 19: 521–539.CrossRefGoogle Scholar
  21. Schulze, D. G., and U. Schwertmann. 1987. The influence of aluminium on iron oxides: XIII. Properties of goethites synthesised in 0.3 M KOH at 25°C. Clay Miner. 22: 83–92.CrossRefGoogle Scholar
  22. Schwertmann, U. 1964. Differenzierung der Eisenoxide des Bodens durch Extraktion mit Ammoniumoxalat-Lösung. Z. Pflanzenernähr. Düng. Bodenk. 105: 194–202.CrossRefGoogle Scholar
  23. Schwertmann, U. 1984. The influence of Al on iron oxides. IX. Dissolution of Al-Goethites in 6 M HCl. Clay Miner. 19: 9–19.CrossRefGoogle Scholar
  24. Smith, K. L., and R. A. Eggleton. 1983. Botryoidal goethite: A transmission electron microscope study. Clays & Clay Miner. 31: 392–396.CrossRefGoogle Scholar
  25. White, A. F., and A. Yee. 1986. Near-surface alkali diffusion into glassy and crystalline silicates at 25°C to 100°C. In Geochemical Processes at Mineral Surfaces. J. A. Davis and K. F. Hayes, eds. Washington: American Chemical Society Symposium Series 323, 586–598.Google Scholar

Copyright information

© The Clay Minerals Society 1995

Authors and Affiliations

  • Allan Bibak
    • 1
  • Joachim Gerth
    • 2
  • Ole K. Borggaard
    • 1
  1. 1.Chemistry DepartmentRoyal Veterinary and Agricultural UniversityFrederiksberg CDenmark
  2. 2.Arbeitsbereich UmweltschutztechnikTechnische Universtät Hamburg-HarburgHamburgGermany

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