Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-15T03:24:34.107Z Has data issue: false hasContentIssue false

Preparation and Characterization of Al-Rich Zn-Al Hydrotalcite-Like Compounds

Published online by Cambridge University Press:  02 April 2024

F. Thevenot
Affiliation:
Institut Français du Pétrole, 1 & 4 Avenue de Bois Préau, B.P. 311, 92506 Rueil-Malmaison Cedex, France
R. Szymanski
Affiliation:
Institut Français du Pétrole, 1 & 4 Avenue de Bois Préau, B.P. 311, 92506 Rueil-Malmaison Cedex, France
P. Chaumette
Affiliation:
Institut Français du Pétrole, 1 & 4 Avenue de Bois Préau, B.P. 311, 92506 Rueil-Malmaison Cedex, France
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.

Hydrotalcite-like compounds, described by the formula [Zn1-xAlx(OH)2][(CO3)x/2 · nH2O], were prepared by coprecipitation methods at 80°C and characterized by bulk chemical analysis, X-ray powder diffraction (XRD), nuclear magnetic resonance (NMR), and scanning-transmission electron microscopy (STEM). An x value of 0.33 was previously assumed to be an upper limit, but recently, Al-rich hydrotalcite-like compounds have been prepared with x as large as 0.44 by hydrothermal synthesis. In the Zn-Al system, Al-rich hydrotalcite was synthesized at normal pressure by coprecipitation. Zn-Al hydrotalcite-like compounds were obtained in the range of x = 0.3 to 0.4. An Al-rich hydrotalcite-like compound with x = 0.44 was formed in mixtures containing large amounts of a poorly crystalline Zn-Al phase. A continuous contraction of the hydrotalcite-like structure occurred as x increased, both the a and c lattice parameters decreasing for x values as large as 0.44. This study illustrates the advantages of using quantitative analytical electron microscopy with high spatial resolution to complement conventional (and bulk) characterization techniques for correlating structural and compositional characteristics of finely divided materials.

Résumé

Résumé

Des composés de type hydrotalcite, de formule générale [Zn1-xAlx(OH)2][(CO3)x/2 · nH2O], ont été préparés par coprécipitation, à 80üC, et caractérisés par différentes techniques telles que: analyse chimique globale, diffraction des rayons-X (DRX), résonance magnétique nucléaire (RMN), et microscopie électronique à transmission (STEM). Jusqu’à présent, la valeur de 0.33 était la limite supérieure admise pour x, mais récemment des phases de type hydrotalcite riches en Al ont été préparées, pour x = 0.44, par synthèse hydrothermale. Pour le système Zn-Al, nos résultats montrent que des composés de type hydrotalcite riches en Al peuvent être synthéitsés à pression normale par coprécipitation. Des phases de type hydrotalcite à base de Zn et Al, ont été obtenues pour des valeurs de x comprises entre 0.3 et 0.4. Une phase hydrotalcite riche en Al avec x = 0.44 a été observée en mélange avec une grande quantité d'une phase à base de Zn et Al très mal cristallisée. Une contraction continue de la structure hydrotalcite est observée lorsque x augmente, les paramètres de maille a et c diminuent lorsque x augmente jusqu’à 0.44. Cette étude illustre les avantages de la microscopie électronique analytique à haute résolution spatiale, utilisée en complément des techniques de caractérisation conventionnelles, pour corréler les caractéristiques structurales et chimiques de matériaux finement divisés.

Type
Research Article
Copyright
Copyright © 1989, The Clay Minerals Society

References

Allmann, R., 1968 The crystal structure of pyroaurite Acta Crystallogr B24 972977.CrossRefGoogle Scholar
Allmann, R., 1970 Doppelschichtstrukturen mit brucit-ähnlichen Schichtionen [MeII I-xMeIII x(OH)2]x+ Chimia 24 99108.Google Scholar
Allmann, R. and Jepsen, H. P., 1969 Die Struktur des Hydrotalkits Neues Jahrb. Mineral. Monatsh 12 544551.Google Scholar
Allmann, R. and Lohse, H.-H., 1966 Die Kristallstruktur des Sjögrenits und eines Umwandlungsproduktes des Koenenits (= Chlor-Manasseits) Neues Jahrb. Mineral. Monatsh 6 161180.Google Scholar
Brindley, G. W. and Kikkawa, S., 1979 A crystal-chemical study of Mg, Al and Ni, Al hydroxy-perchlorates and hydroxy-carbonates Amer. Mineral 64 836843.Google Scholar
Brown, G., Brindley, G. W. and Brown, G., 1980 Associated minerals Crystal Structures of Clay Minerals and their X-ray Identification London Mineralogical Society 397400.Google Scholar
Gastuche, M. C., Brown, G. and Mortland, M. M., 1967 Mixed magnesium-aluminium hydroxides Clay Miner 7 177201.CrossRefGoogle Scholar
Ingram, L. and Taylor, H. F. W., 1967 The crystal structures of sjörgrenite and pyroaurite Mineral. Mag 36 465479.Google Scholar
Lynch, J., Raatz, F. and Dufresne, P., 1987 Characterization of the textural properties of dealuminated HY forms Zeolites 7 333340.CrossRefGoogle Scholar
Miyata, S., 1975 The syntheses of hydrotalcite-like compounds and their structures and physico-chemical proper-ties—I: The systems Mg2+-Al3+-NO3 -, Mg2+-Al3+-Cl-, Mg2+-Al3+-ClO4-, Ni2+-Al3+-Cl-, and Zn2+-Al3+-Cl- Clays & Clay Minerals 23 369375.CrossRefGoogle Scholar
Miyata, S., Kumura, T. and Shimada, M. (1975) Composite metal hydroxides: U.S. Patent 3,879,523, 72 pp.Google Scholar
Pausch, I., Lohse, H.-H. Schürmann, K. and Allmann, R., 1986 Syntheses of disordered and Al-rich hydrotalcite-like compounds Clays & Clay Minerals 34 507510.CrossRefGoogle Scholar
Reichle, W. T., Kang, S. Y. and Everhardt, D. S., 1986 The nature of the thermal decomposition of a catalytically active anionic clay mineral J. Catalysis 101 352359.CrossRefGoogle Scholar
Schutz, A. and Biloen, P., 1987 Interlamellar chemistry of hydrotalcites. I. Polymerisation of silicate anions J. Solid State Chem 68 360368.CrossRefGoogle Scholar
Serna, C. J., Rendon, J. L. and Iglesias, J. E., 1982 Crystal-chemical study of layered [Al2Li(OH)6]+X- ⊙ nH2O Clays & Clay Minerals 30 180184.CrossRefGoogle Scholar
Sissoko, I., Iyagba, E. T., Sahai, R. and Biloen, P., 1985 Anion intercalation and exchange in Al(OH)3-derived compounds J. Solid State Chem 60 283288.CrossRefGoogle Scholar
Sugier, A. and Freund, E. (1978) Process for manufacturing alcohols, particularly linear saturated primary alcohols from synthesis gas: U.S. Patent 4,122,110, 8 pp.Google Scholar
Sugier, A. and Freund, E. (1981) Process for manufacturing alcohols and more particularly saturated linear primary alcohols from synthesis gas: U.S. Patent 4,291,126, 8 pp.Google Scholar
Szymanski, R. and Lynch, J. (1986) Quantitative X-ray microanalysis of divided solids in the STEM: in Proc. 11th Int. Conf. X-Ray Optics and Microanalysis, Brown, J. D. and Packwood, R. H., eds., University of Western Ontario Graphic Services, London, Canada, 412415.Google Scholar
Szymanski, R., Travers, C., Chaumette, P., Courty, P.h. Durand, D., Delmon, B., Grange, P., Jacobs, P. A. and Poncelet, G., 1987 Comparison of the quantitative studies by STEM of hydrated hydroxycarbonates and related mixed oxide catalysts for CO hydrogenation to alcohols Preparation of Catalysts IV Amsterdam Elsevier 739751.Google Scholar
Taylor, H. F. W., 1969 Segregation and cation-ordering in sjögrenite and pyroaurite Mineral. Mag 37 338342.CrossRefGoogle Scholar
Taylor, H. F. W., 1973 Crystal structures of some double hydroxide minerals Mineral. Mag 39 377389.CrossRefGoogle Scholar
Toulhoat, H., Plumail, J. C., Houpert, C.h. Szymanski, R., Bourseau, P. and Muratat, G., 1987 Modeling RDM catalysts deactivation by metal sulfides deposits: An original approach supported by HREM investigations and pilot tests results Symposium on Advances in Residue Upgrading, American Chemical Society, Denver, 1987, ACS Preprints 32 463.Google Scholar