Goethite a-FeOOH

Goethite (named after J.W. von Goethe) is isostructural with diaspore and with various other metal oxides (Tab. 2.1). It has an orthorhombic unit cell with a = 0.9956 nm, h = 0.30215 nm, c = 0.4608 nm (Goldsztaub, 1932 Hoppe, 1941 Forsyth [Pg.14]

Compound Face shared Fe-Fe distances (nm)Jbr Edge shared Corner shared octahedra octahedra Ref. [Pg.16]

The goethite structure consists of an hep array of anions (0 and OH ) stacked along the [010] direction with Fe ions occupying half the octahedral interstices within a layer (Fig. 2.4a-c). The Fe ions are arranged in double rows separated by double rows of empty sites (Fig. 2.4a, c) at the crystal surfaces the empty sites appear as grooves (Fig. 2.4d). [Pg.16]

The goethite structure contains two types of O atoms designated as Oi and On (Fig. 2.4e). On the 0 site, the O atom is shared between octahedra of two different double chains, whereas the On atom is shared between octahedra in the same chain and is also linked to the proton. Neutron scattering has shown that the On-On distance is [Pg.16]

1) The space group was changed from Pbnm to Pnma leading to a c b a and c b. [Pg.16]

Sigg, L., and W. Stumm (1981), The Interaction of Anions and Weak Adds with the Hydrous Goethite (a-FeOOH) Surface", Colloids and Surfaces 2, 101-117. [Pg.42]

Titration calorimetry and cylindrical internal reflection-Fourier transform infrared (CIR-FTIR) spectroscopy are two techniques which have seldom been applied to study reactions at the solid-liquid interface. In this paper, we describe these two techniques and their application to the investigation of salicylate ion adsorption in aqueous goethite (a-FeOOH) suspensions from pH 4 to 7. Evidence suggests that salicylate adsorbs on goethite by forming a chelate structure in which each salicylate ion replaces two hydroxyls attached to a single iron atom at the surface. [Pg.142]

To put things into perspective, we. can broadly classify these analytical methods into bulk, dry surface, and in situ interfacial techniques. This chapter focuses on the last category, illustrating two in situ techniques used to study anion binding at the goethite (a-FeOOH)-water interface titration calorimetry and cylindrical internal reflection-Fourier transform infrared (CIR-FTIR) spectroscopy. In fact, CIR-FTIR could prove to be extremely powerful, since it allows direct spectroscopic observation of ions adsorbed at the mineral-water interface. [Pg.143]

Oxide composition and lattice structure influences the coordin-ative environment of surface sites, and should have an impact on rates of ligand substitution. Hematite (Fe203), goethite (a-FeOOH), and lepidocrocite (y-FeOOH), for example, are all Fe(III) oxide/ hydroxides, but may exhibit different rates of surface chemical... [Pg.454]

Hydroxides are also prone to surface modification by OPCA, as shown by the results reported for boehmite (y-AlOOH) [142, 160, 161] and goethite (a-FeOOH) [162, 163]. [Pg.163]

Cornell, R.M. (1991) Simultaneous incorporation of Mn, Ni and Co in the goethite (a-FeOOH) structure. Clay Min. 26 427-430 Cornell, R.M. (1992) Preparation and properties of Si substituted akaganeite (P-FeOOH). Z. Pflanzenemahr. Bodenk. 155 449-453 Cornell, R.M. Giovanoli, R. Schindler, P.W. (1987) Effect of silicate species on the transformation of ferrihydrite into goethite and hematite in alkaline media. Clays Clay Min. 35 12-28... [Pg.571]

Cornell, R.M. Posner, A.M. Quirk, J.P. (1975) The complete dissolution of goethite. J. Appl. Chem. Biotechnol. 25 701-706 Cornell, R.M. Posner, A.M. Quirk, J.P. (1976) Kinetics and mechanisms of the acid dissolution of goethite (a-FeOOH). J. inorg. nucl. Chem. 38 563-567... [Pg.571]

Davis, A.P. Upadhyaya, M. (1996) Desorption of cadmium from goethite (a-FeOOH). Water Res. 30 1894-1904... [Pg.573]

De Endredy, A.S. (1963) Estimation of free iron oxides in soils and clays by a photolytic method. Clay Min. Bull. 5 209-217 de Faria, D.L.A. Venancio Silva, S. de Oliveira, M.T. (1997) Raman Microspectroscopy of some iron oxides and oxyhydroxides. J. Raman Spectrosc. 28 873-878 De Grave, E. Vandenberghe, R.E. (1986) 57Fe Mossbauer effect study of well-crystallized goethite (a-FeOOH) Hyp. Interact. 28 643-646... [Pg.573]

Derie, R. Ghodsi, M. Calvo-Roche, C. (1976) DTA study of the dehydration of synthetic goethite a-FeOOH. J. Thermal Analysis 9 435-440... [Pg.574]

Diakonov, I. Khodakovsky I. Schott, J. Sergeeva, E. (1994) Thermodynamic properties of iron oxides and hydroxides. I. Surface and bulk thermodynamic properties of goethite (a-FeOOH) up to 500 K. Fur. J. Min. 6 967-983... [Pg.575]

The interfadal electrochemistry of goethite (a-FeOOH) espedally the effect of CO2 contamination. J. Electroanal. Chem. 105 161—... [Pg.577]

The magnetic structure and hyperfme field of goethite (a-FeOOH). J. Phys. Cl 179-188... [Pg.580]

Gerth, J. Brummer, G. (1983) Adsorption und Festlegung von Nickel, Zink und Cadmium durch Goethit (a-FeOOH). Fresenius Z. [Pg.583]

Goodman, B.A. Cheshire, M.V. (1987) Characterization of iron-fulvic acid complexes using Mossbauer and FPR spectroscopy. Sci. Total Fnviron. 62 229-240 Goodman, B.A. Lewis, D.G. (1981) Mossbauer spectra of aluminous goethites (a-FeOOH). J. Soil Sci. 32 351-363 Goodman, B.A. (1988) An introduction to physical and chemical principles. In Studd, J.W. Goodman, B.A. Schwertmann, U. (eds.) Iron in soils and day minerals. D. Reidel Publ. Co., Dordrecht, Holland, NATO ASI Sen 217 19-36... [Pg.585]

Gunneriusson, L. (1994) Composition and stability of Cd(II) chloro and Cd(II) hydroxo complexes at the goethite (a-FeOOH)/water interface. J. Colloid Interface Sd. 163 484-492 Gunten, U. von Schneider, W. (1991) Primary produds of oxygenation of iron(II) at an oxic/ anoxic boundary nucleation, agglomeration and ageing. J. Colloid Interface Sd. 145 127-139... [Pg.586]

Parfitt, R.L. Atkinson, R.J. (1976) Phosphate adsorption on goethite (a-FeOOH). Nature 264 740-742... [Pg.614]

Parfitt, R.L. Smart, R.S.C. (1977) Infrared spectra from binuclear bridging complexes of sulphate adsorbed on goethite (a-FeOOH). J. Chem. Soc. Faraday Trans. I. 73 796-802 Parfitt, R.L. Smart, R.S.C. (1978) The mechanism of sulfate adsorption on iron oxides. Soil Sci. Soc. Am. J. 42 48-50 Parfitt, R.L. (1980) Chemical properties of variable charge soils. In Theng, B.K. (ed.) Soils with variable charge. N. Z. Soc. Soil Sci., Lower Hutt. N. Z., 167-194 Parfitt, R.L. (1982) Competitive adsorption of phosphate and sulphate on goethite (a-FeOOH) A note. New Zealand J. Sci. 25 147-148... [Pg.615]

Persson, P., Nordin, J., Rosenquist, J., Lovgren, L., Ohman, L-0. Sjoberg, S. (1998) Comparison of the adsorption of o-phthalate on bohmite (a-AlOOH), aged a-Al203 and goethite (a-FeOOH) J. Coll. Interf. Sd. 206 252-266... [Pg.616]

Farmer, V.C. (1975) Adsorption of carbon dioxide on goethite (a-FeOOH) surfaces, and its implications for anion adsorption. J. [Pg.621]

Interfacial chemistry of dissolving metal oxide particles Dissolution by organic acids. Chap. 14 p. 513-540, Interfacial dynamics (Ed. N. Kallay) Marcel Dekker N.Y. Sampson, C.F. (1969) The lattice parameters of natural single crystal and synthetically produced goethite (a-FeOOH). Acta Cryst. B 25 1683-1685... [Pg.622]

Sigg, L. Stumm,W. (1981) The interaction of anions and weak acids with the hydrous goethite (a-FeOOH) surface. Colloids Surfaces 2 101-117... [Pg.629]

Tejedor-Tejedor, M.l. Anderson, M.A. (1986) In situ" attenuated total reflectance Fourier transform infrared studies of the goethite (a-FeOOH)-aqueous solution interface. Langmuir 2 203-210... [Pg.635]

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