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P-FeOOH

Figure 6 shows transmission electron micrographs of Au particles supported by (a) monocrystalline ellipsoidal (B), (b) monocrystalline pseudocubic, and (c) monocrystalline platelet-type hematite particles (see also Figure 5 for Au particles on polycrystalline ellipsoidal (A) particles). Figure 7 shows Au particles deposited on (a) a-FeOOH, (b) P-FeOOH, (c) ZrOj (A), (d) ZrOj (B), and (e) Ti02 (anatase). [Pg.393]

Each needle-like crystal of p-FeOOH is known to consist of a bundle of much thinner suhcrystals. [Pg.395]

Akaganeite, P-FeOOH, is named after the Akagane mine in Japan where it was first discovered (Mackay, 1962). It occurs rarely in nature and is found mainly in Cl-rich environments such as hot brines and in rust in marine environments. Unlike the other FeOOH polymorphs, it has a structure based on body centered cubic packing of anions (bcp) (hollandite structure) and contains a low level of either chloride or fluoride ions. It has a brown to bright yellow colour. [Pg.6]

Fig. 10.14 a) SEM of three smetic domains I, II and III of p-FeOOH crystals. In domain I the crystals stand upright so that only the ends are visible, A/hereas in domains II and III, only the sides of the crystals are visible, b) SEM of domain I. c) Schematic figure of the arrangement of crystals in the three domains (Reprinted from Maeda Maeda, copyright 1996, A/ith permission and Courtesy, H. Maeda). [Pg.251]

Buchwald, U.F. Clarke, R.S.Jr. (1989) Corrosion of Fe-Ni alloys by Cl-containing akaga-neite (P-FeOOH) The Antarctic meteorite case. Am. Min. 74 656-667 Buckland, A.D. Rochester, C.H. Topham,... [Pg.565]

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]

Hoins, U. Charlet, L. Sticher, H. (1993) Ligand effect on the adsorption of heavy metals. The sulphate-cadmium goethite case. Water, Air, Soil Pollution 68 241-255 Holm, G. (1985) Substitution selectivity of some transition elements (Cr, Mn, Co, Ni, Cu, Zn) during formation of P-FeOOH. Geologiska Foreningsi Stockholm Forhandlingar 107 297-300... [Pg.590]

Atlantis II Deep (Red Sea) and the uptake of amino acids by synthetic P-FeOOH Cln. Geochim. Cosmochim. Acta 47 1465-1470 Holm,T.R., Anderson, M.A., Iverson, D.G. Stanforth, R.S. (1979) Heterogeneous interaction of arsenic in aquatic systems. ACS Symposium Ser. Chemical modelling of aqueous systems Speciation, sorption, solubility, kinetics. 711-736... [Pg.590]

Hotta,Y Ozeki, S. Suzuki,T. Imal, S. Ka-neko, S. (1991) Surface characterization of titanated a-Fe203. Langmuir 7 2649—2654 Howe, A.T. Gallagher, K.J. (1975) Mossbauer studies in the colloidal system P-FeOOH — P-Fe20j Structures and dehydration mechanism. J. Chem. Soc. Faraday Trans. I. 71 22-34 Hsi, C.D. Langmuir, D. (1985) Adsorption of uranyl onto ferric oxyhydroxides Application of the surface complexation site-binding model. Geochim. Cosmochim. Acta 49 1931-1941... [Pg.590]

Inouye, K. Ichimura, H. Kaneko, K. Ishi-kawa,T. (1974) The effect of copper(II) on the formation and thermal change of synthetic P-FeOOH. Bull. Chem. Soc. Japan 47 743-744... [Pg.591]

Ishikawa, T. Inouye, K. (1975) Role of chlorine in P-FeOOH on its thermal change and reactivity to sulfur dioxide. Bull. Chem. Soc. Japan 48 1580-1584... [Pg.591]

Keller, P. (1967) Quantitative, rontgenogra-phische Phasenanalyse verschiedener Rostty-pen. Werkst. und Korr. 10 865-878 Keller, P. (1969) Vorkommen, Entstehung und Phasenumwandlung von P-FeOOH in Rost. Werkstoffe und Korrosion 20 102-108 Keller, P. (1970) Eigenschaften von (Cl, E,... [Pg.596]

Loghman-Adham, M. (1999) Phosphate binders for control of phosphate retention in chronic renal failure. Pediatr. Nephrol. 13 701-708 Lorenz, M. Kempe, G. (1987) Substitution des Eisen(III) im p-FeOOH. Wiss. Zeitschr. [Pg.601]

Maeda, H. Maeda,Y. (1996) Atomic force microscopy studies for investigating the smecti-tic structures of colloidal crystals of P-FeOOH. Langmuir 12 1446-1452... [Pg.603]

Naono, H. Fujiwara, R. (1980) Micropore formation due to thermal decomposition of ad-cular microcrystals of a-FeOOH. J. Colloid Interface Sd. 73 406-415 Naono, H. Nakai, K. (1989) Thermal decomposition of P-FeOOH fine partides. J. Colloid Interface Sd. 128 146-156 Naono, H. Fujiwara, R. Sugioka, H. Sumiya,... [Pg.612]

K. Yanazawa, H. (1982) Micropore formation due to thermal decomposition of adcular microcrystals of P-FeOOH. J. Colloid Interface Sd. 87 317-332... [Pg.612]

Naono, H. Sonoda, J. Oka, K. Hakuman, M. (1993) Evaluation of microporous texture of undecomposed and decomposed p-FeOOH fine particles by means of adsorption isotherms of nitrogen gas and water vapor. Proc. IVth Int. Conf on Fundamentals of Adsorption, Kyoto 1992, 467-474 Naumann, F. (1855) Elemente der Mineralogie. 4. Auflage, Leipzig... [Pg.612]

Paterson, E. Tait, J.M. (1977) Nitrogen adsorption on synthetic akaganeite and its structural implications. Clay Min. 12 345-352 Paterson, E. Swaffield, R. Clark, D.R. (1982) Thermal decomposition of synthetic akaganeite (P-FeOOH). Thermochim. Acta 54 201-211... [Pg.615]

Paterson, R. Rahman, H. (1984a) The ion exchange properties of crystalline inorganic oxide-hydroxides. Part II Exclusion of perchlorate from p-FeOOH by an ion sieve mechanism. J. Colloid Interface Sci. 97 423-427... [Pg.615]

Watson, I. (1979) Iron oxide pigments. Colour-frd competitors between natural and synthetic. Minerals in Industry, Aug., 43—51 Watson, J.H.L., Cardell, R.R.Jr. Heller, W. (1962) The internal structure of colloidal crystals of P-FeOOH and remarks on their assemblies in Schiller layers. J. Phys. Chem. 66 1757-1763... [Pg.642]

Plate 10.1 Optical microscope images ofthe irridescent regions on the surface ofthe P-FeOOH sol (x650) (Reprinted from Maeda, Maeda, copyright 1996. With permission and Courtesy, H. Maeda). [Pg.668]

Hydrolysis of FeCf Solutions. Aging of ferric chloride solutions yields, as a rule, either colloidal akageneite (p-FeOOH) or hematite (a-Fe203). However, the two forms are closely related in the formation of the precipitates (95,142). [Pg.19]

Fig. 1.1.13 Concentration domains of solutions containing FeClj and HCI aged at 100°C for 24 h (upper) and for 1 week (lower). N, no particle formation. Particle shapes D. double ellipsoids E, ellipsoidal 1, irregular of varying sizes R. rod-like S, spherical. Pairing of symbols indicates a mixture of corresponding particles in the suspension. Particle composition R, p-FeOOH all other particles, a-Fe2Oi. (From Ref. 65.)... Fig. 1.1.13 Concentration domains of solutions containing FeClj and HCI aged at 100°C for 24 h (upper) and for 1 week (lower). N, no particle formation. Particle shapes D. double ellipsoids E, ellipsoidal 1, irregular of varying sizes R. rod-like S, spherical. Pairing of symbols indicates a mixture of corresponding particles in the suspension. Particle composition R, p-FeOOH all other particles, a-Fe2Oi. (From Ref. 65.)...
Precipitation of ferric hydroxide gel was also observed in the preparation of spindlelike hematite (a-Fe203) particles in a dilute ferric chloride solution in the presence of phosphate (9). In this case, however, the positive role of the gel was not definite since similar uniform hematite paricles were obtained as well in homogeneous systems in the presence of the same anions (9). Also, Hamada and Matijevic (10) prepared uniform particles of pseudocubic hematite by hydrolysis of ferric chloride in aqueous solutions of alcohol (10-50%) at I00°C for several days. In this reaction, it was observed that acicular crystals of (3-FeOOH precipitated first, and then they dissolved with formation of the pseudocubic particles of hematite. The intermediate P-FeOOH appears to work as a reservoir of the solute to maintain an ideal supersaturation for the nucleation and growth of the hematite. Since the (3-FeOOH as an intermediate and the pseudocubic shape tire not peculiar to the alcohol/water medium... [Pg.63]

Fig. 1.3.10 SEM images of (a) pseudocubic, (b) ellipsoidal, (c) peanut-type, and (d) platelet-type hematite particles. The particles of (a), (b), and (c) were prepared under the same conditions as those of the particles in Fig. 1.3.7 but with 10-2 and 3.0 X 10-2 mol dm-3 Na2S04 for (b) and (c), respectively. The platelet particles in (d) were prepared by aging a P-FeOOH suspension ( 0.9 mol dm-3) at 70°C for 8 days in a medium of 2 mol dm-3 NaCl and 7.5 mol dm-3 NaOH. (From Refs. 16 and 20.)... Fig. 1.3.10 SEM images of (a) pseudocubic, (b) ellipsoidal, (c) peanut-type, and (d) platelet-type hematite particles. The particles of (a), (b), and (c) were prepared under the same conditions as those of the particles in Fig. 1.3.7 but with 10-2 and 3.0 X 10-2 mol dm-3 Na2S04 for (b) and (c), respectively. The platelet particles in (d) were prepared by aging a P-FeOOH suspension ( 0.9 mol dm-3) at 70°C for 8 days in a medium of 2 mol dm-3 NaCl and 7.5 mol dm-3 NaOH. (From Refs. 16 and 20.)...
See other pages where P-FeOOH is mentioned: [Pg.395]    [Pg.396]    [Pg.397]    [Pg.329]    [Pg.257]    [Pg.13]    [Pg.3]    [Pg.8]    [Pg.250]    [Pg.567]    [Pg.582]    [Pg.590]    [Pg.595]    [Pg.595]    [Pg.611]    [Pg.621]    [Pg.2]    [Pg.19]    [Pg.63]    [Pg.65]    [Pg.68]    [Pg.72]    [Pg.677]   


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8-FeOOH

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