Abstract
Solutions containing hydroxy-FeAl oligocations (HFA) were prepared by two procedures: (1) treatment of a mixture of FeCl3 and AlCl3 with aqueous Na2CO3, followed by aging of the product and (2) preliminary preparation and aging of hydroxy-Al13 oligocations followed by reaction of the latter with aqueous FeCl3. Ion-exchange of Na-montmorillonite with HFA yield pillared clay (designated as FeAl-PILC) with d(001) values of 1.98–1.56 nm and a surface area of 230 m2/g. The pillar structure, thermal stability, surface acidity, and reduction behavior of the pillared clays were determined by 27Al-NMR, XRD, DTA, Mössbauer spectroscopy, Py-IR, TPD, TPR. Fe/Al ratios greatly affect the pillar structure, surface area and thermal stability of FeAl-PILC. The pillar in FeAl-PILC with Fe/Al ratio <0.5 has a Keggin structure, similar to that of Al-PILC, but the pillar structures of FeAl-PILC with Fe/Al ≥0.5 are the ferric tripolymer species similar to those of Fe-PILC. The basal spacings, surface area, and thermal stability are decreased with increasing Fe/Al ratio. There is relatively strong interaction between Fe and Al in the pillars. The interaction is enhanced with decreasing Fe/Al ratio. Reduction of the Fe phase in FeAl-PILC was reduced by the interaction of Fe with Al.
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Akitt, J. and Farthing, A. (1981) Aluminium-27 nuclear magnetic resonance studies of the hydrolysis of aluminium(III): J. Chem. Soc. (Datton) 7, 1606–1628.
Brindley, G. W. and Sempels, R. E. (1977) Preparation and properties of some hydroxy-aluminum beidellites: Clay Miner. 12, 229–236.
Endo, T., Mortland, M. M., and Pinnavaia, T. J. (1980) Intercalation of silica in smectite: Clays & Clay Minerals 28, 105–110.
Endo, T., Mortland, M. M., and Pinnavaia, T. J. (1981) Properties of silica-intercalated hectorite: Clays & Clay Minerals 29, 153–156.
Garten, R. L. and Ollis, D. F. (1974) The chemical state of iron in reduced PdFe/Al2O3 catalysts: J. Catal. 35, 232–246.
Hurst, N. W. (1982) Temperature programmed reduction: Catal. Rev.-Sci. Eng. 24, 233–309.
Lahav, N., Shani, U., and Shabtai, J. (1978) Cross-linked smectites I Synthesis and properties of hydroxy-aluminum montmorillonite: Clays & Clay Minerals 26, 107–115.
Lee, W. Y., Raythatha, R. H., and Tatarchuk, B. J. (1989) Pillared-clay catalysts containing mixed-metal complexes, I Preparation and characterization: J. Catal. 115, 159–179.
Leoppert, R. H., Mortland, M. M., and Pinnavaia, T. J. (1979) Synthesis and properties of heatstable expanded smectite and vermiculite: Clays & Clay Minerals 27, 201–208.
Matsuda, T., Nagashima, H., and Kikuchi, E. (1988) Physical and catalytic properties of smectite clays pillared by alumina in disproportionation of 1,2,4-trimethylbenzene: Appl. Catal. 45, 171–182.
Occelli, M. L. and Finseth, D. H. (1986) Preparation and characterization of pillared hectorite catalysts: J. Catal. 99, 316–326.
Shabtai, J. (1980) Cross-linked montmorillonite molecular sieves: U.S. Patent 4,216,188, 6 pp.
Shabtai, J. and Fijal, J. (1986) A novel class of hydroprocessing catalysts and preparation methods: U.S. Patent 4,579,832, 12 pp.
Tichit, D., Fajula, F., and Figueras, F. (1985) Thermal stability and acidity of AP3+ ion cross-linked smectites: in Catalysis by Acids and Bases, Elsevier Science Publishers, B.V. Amsterdam, 351–360.
Vaughan, D. E. W., Lussier, R. J., and Magee, J. (1979) Pillared interlayered clay materials useful as catalysts and sorbents: U.S. Patent 4,176,090, 7 pp.
Vaughan, D. E. W. (1987) Multimetallic pillared interlayered clay products and processes of making them: U.S. Patent 4,666,877, 6 pp.
Yamanaka, S. and Hattori, H. (1988) Iron oxide pillared clays: Catalysis Today 2, 261–270.
Zhao, D. Y. (1990) Synthesis and characterization of pillared clays containing mixed-metal complexes: Ph.D. thesis, Jilin University, ChangChun, P. R. China.
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Zhao, D., Wang, G., Yang, Y. et al. Preparation and Characterization of Hydroxy-Feal Pillared Clays. Clays Clay Miner. 41, 317–327 (1993). https://doi.org/10.1346/CCMN.1993.0410306
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DOI: https://doi.org/10.1346/CCMN.1993.0410306