Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-24T12:09:24.407Z Has data issue: false hasContentIssue false

Redox Characterization of the Surfaces of Seven Iron-Bearing Minerals: Use of Molecular Probes and UV-Visible Spectroscopy

Published online by Cambridge University Press:  28 February 2024

Y. Shane Yu*
Affiliation:
Dyn-Corp Technology Applications, Inc., 960 College Station Road, Athens, Georgia 30605-2700
George W. Bailey
Affiliation:
Ecosystems Research Division, National Exposure Research Laboratory, U.S. Environmental Protection Agency, 960 College Station Road, Athens, Georgia 30605-2700
*
Current address: Equifax, Inc., Decision Systems, External Maildrop 425, 1525 Windward Concourse, Alpharetta, Georgia 30202.
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.

Redox properties of iron-bearing mineral surfaces may play an important role in controlling the transport and transformation of pollutants into ground waters. Suspensions of seven iron-bearing minerals were reacted with pH and redox indicators under anaerobic conditions at the pH of the natural suspension. The responses of the indicators to the mineral surfaces were monitored by UV-visible spectroscopy using a scattered transmission technique. The Hammett surface acidity function (Hs) and the surface redox potential (Ehs) of these iron-bearing minerals were measured. These measured values were used to calculate Eh values for the seven minerals: goethite = +293 mV; chlorite = +290 mV; hematite = +290 mV; almandite = +282 mV; ferruginous smectite = +275 mV; pyrite = +235 mV; and Na-vermiculite = +223 mV. Calculated surface redox potentials of minerals are different from their potentials measured by platinum electrode in bulk suspensions. UV-visible spectroscopy provides a quick and non-destructive way of monitoring organic probe response at the mineral surface.

Type
Research Article
Copyright
Copyright © 1996, The Clay Minerals Society

References

Bailey, G.W. and Karickhoff, S.W.. 1973. An ultraviolet spectroscopic method for monitoring surface acidity of clay minerals under varying water content. Clays Clay Miner 21: 471477.CrossRefGoogle Scholar
Bartlett, R.J.. 1986. Soil redox behavior. In: Sparks, D.L., editor. Soil physical chemistry. Boca Raton, FL: CRC Press. p 179207.Google Scholar
Bates, R.G.. 1959. Electrode potentials: Treatise on analytical chemistry, Part 1. In: Kolthoff, I.M., Elving, P.J., editors. New York: Interscience. p 319359.Google Scholar
Bohn, H.L., McNeal, B.L. and O'Connor, G.A.. 1979. Soil chemistry. New York: John Wiley and Sons. p 247271.Google Scholar
Brown, G., Newman, A.C.D., Rayner, J.H. and Weir, A.H.. 1978. The structures and chemistry of soil clay minerals. In: Greenland, D.J., Hayes, M.H.B., editors. The chemistry of soil constituents. New York: John Wiley and Sons. p 29178.Google Scholar
Cenens, J. and Schoonheydt, R.A.. 1988. Visible spectroscopy of methylene blue on hectorite, laponite B, and barasym in aqueous suspension. Clays Clay Miner 36: 214224.CrossRefGoogle Scholar
Clark, W.M.. 1960. Oxidation-reduction potentials of organic systems. Baltimore, MD: Williams and Wilkins. p 1106.Google Scholar
Conant, J.B.. 1926. The electrochemical formulation of the irreversible reduction and oxidation of organic compounds. Chem Rev 3: 140.CrossRefGoogle Scholar
Goldhaber, M.B.. 1983. Experimental study of metastable sulfur oxyanion formation during pyrite oxidation. Am J Sci 283: 193217.CrossRefGoogle Scholar
Guenther, W.B.. 1975. Chemical equilibrium. New York: Plenum Press. p 207228.CrossRefGoogle Scholar
Hewitt, L.F.. 1950. Oxidation-reduction potentials in bacteriology and biochemistry. Edinburgh, UK: Livingstone. p 1936.Google Scholar
Jackson, M.L.. 1956. Soil chemical analysis—Advanced course. Published by the author, Dept. of Soils, Univ. of Wisconsin, Madison, WI. p 100115.Google Scholar
Karickhoff, S.W. and Bailey, G.W.. 1976. Protonation of organic bases in clay-water systems. Clays Clay Miner 24: 170176.CrossRefGoogle Scholar
Light, T.S.. 1972. Standard solution for redox potential measurements. Anal Chem 44: 10381039.CrossRefGoogle Scholar
Lindsay, W.. 1988. Solubility and redox equilibria of iron compounds in soils. In: Stucki, J.W., Goodman, B.A., Schwertmann, U., editors. Iron in soil and clay minerals. Norwell, MA: Kluwer Academic Publishers. p 3761.CrossRefGoogle Scholar
Liu, Z.. 1985. Oxidation-reduction potential. In: Yu, T., editor. Physical chemistry of paddy soils. Beijing: Science Press. p 126.Google Scholar
Ljungdahl, L.G. and Andreesen, J.R.. 1978. Formate dehydrogenase, a selenium-tungsten enzyme from Clostridium thermoaceticum. Meth in Enzymol 53: 360372.CrossRefGoogle ScholarPubMed
Loughnan, F.C.. 1969. Chemical weathering of the silicate minerals. New York: American Elsevier. p 426.Google Scholar
Luther, G.W.. 1987. Pyrite oxidation and reduction: Molecular orbital theory considerations. Geochim Cosmochim Acta 51: 31933199.CrossRefGoogle Scholar
Moses, C.O., Nordstrom, D.K., Herman, J.S. and Mills, A.L.. 1987. Aqueous pyrite oxidation by dissolved oxygen and by ferric iron. Geochim Cosmochim Acta 51: 15611571.CrossRefGoogle Scholar
Murad, E. and Fischer, W.R.. 1988. The geobiochemical cycle of iron. In: Stucki, J.W., Goodman, B.A., Schwertmann, U., editors. Iron in soils and clay minerals. Norwell, MA: Kluwer Academic Publishers. p 118.Google Scholar
Patrick, W.H. Jr. 1980. The role of inorganic redox systems in controlling reduction in paddy soils. In: Editor, China, Inst Soil Sci, Proc. Symposium on Paddy Soil. Nanjing, China: Academia Sinica. p 107117.Google Scholar
Perrin, D.D., Dempsey, B. and Serjeant, E.P.. 1981. Prediction of pKa for phenols, aromatic carboxylic acids and aromatic amines. In: Perrin, D.D., Dempsey, B., Serjeant, E.P., editors. pKa prediction for organic acids and bases. Norwell, MA: Chapman and Hall. p 4452.CrossRefGoogle Scholar
Ponnamperuma, F.N., Tianco, E.M. and Loy, T.. 1967. Redox equilibria in flooded soils. I. The iron hydroxide system. Soil Sci 103: 374382.CrossRefGoogle Scholar
Ponnamperuma, F.N.. 1972. The chemistry of submerged soils. In: Brady, N.C., editor. Advances in agronomy. New York: Academic Press. p 2996.Google Scholar
Schwertmann, U.. 1971. Transformation of hematite to goethite in soils. Nature 232: 624625.CrossRefGoogle ScholarPubMed
Schwertmann, U. and Taylor, R.M.. 1989. Iron oxide. In: Dixon, J.B., Weed, S.B., editor. Minerals in soil environments. Madison, WI: Soil Sci Soc Am. p 379438.Google Scholar
Stumm, W. and Morgan, J.J.. 1985. The conceptual significance of pe. A comment on J.D. Hostettler's paper, electrode electrons, aqueous electrons and redox potentials in natural waters. Am J Sci 285: 856859.CrossRefGoogle Scholar
Wolfe, N.L., Mingelgrin, U. and Miller, G.C.. 1990. Abiotic transformations in water, sediment, and soil. In: Cheng, H.H., editor. Pesticides in the soil environment: Processes, impact, and modeling. SSSA Book Series 2, Madison, WI: Soil Sci Soc Am. p 103168.Google Scholar
Wurmser, R. and Banerjee, R.. 1964. Oxidation-reduction potentials. Compr Biochem 12: 6288.Google Scholar
Zobell, C.E.. 1946. Studies on redox potential of marine sediments. Am Assoc Pet Geol Bull 30: 477513.Google Scholar