Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-02T03:02:07.929Z Has data issue: false hasContentIssue false
  • English
  • Français

Thermal evolution of Mg-Al-CO3 hydrotalcites

Published online by Cambridge University Press:  09 July 2018

Ts. Stanimirova ,
N. Piperov ,
N. Petrova  and
G. Kirov
Ts. Stanimirova
Affiliation:
Department of Mineralogy, Sofia University, 15 Tzar Osvoboditel, Sofia 1000
N. Piperov
Affiliation:
Institute of Inorganic Chemistry, Bulgarian Academy of Sciences, Academic G. Bonchev Str. bl. 11, Sofia 1113
N. Petrova*
Affiliation:
Central Laboratory of Mineralogy and Crystallography, Bulgarian Academy of Sciences, Academic G. Bonchev Str. bl. 107, Sofia 1113, Bulgaria
G. Kirov
Affiliation:
Department of Mineralogy, Sofia University, 15 Tzar Osvoboditel, Sofia 1000
*
*E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

The thermal decomposition of hydrotalcite (HT), with chemical composition Mg1-xAlx(OH)2(CO3)x/2.(1-3x/2)H2O, (0.20 < x ≤ 0.33), is a complex sequence of dehydration, dehydroxylation and decarbonization and leads to the formation of a series of metaphases: HT-D (dehydrated HT), HT-B (partially dehydroxylated HT) and MO (mixed oxides with periclase-like structure). The evolution of water and CO2 in natural and synthetic hydrotalcites (a Mg/Al ratio between 2:1and 3.7:1), heated to 800°C, was investigated by differential thermal analysis, thermogravimetry and evolved gas analysis. At least six endothermic and two exothermic effects were established by computer-aided resolving of the curves. The formation of each HT metaphase was related to the release of a discrete number of water molecules depending on the Al content in the samples and each appeared as a corresponding endothermic peak in the DTA curves. The exothermic processes associated with the crystallization of HT-B and MO metaphases were specified by decomposition of DTA curves. The evolution of CO2 during the thermal decomposition of the carbonate groups was found to be different for the samples studied. The preservation of CO3 even at high temperatures was established for synthetic samples with a high Al content. The release of volatile H2O and CO2 (which comprise ~40% of the sample mass) provokes fine cracking both along and across the layers.

Keywords

hydrotalciteDTATGevolving gas analysis
Type
Research Article
Information
Clay Minerals , Volume 39 , Issue 2 , June 2004 , pp. 177 - 191
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Allmann, R. & Jepsen, H.P. (1969) Die Struktur des Hydrotalkits. Neues Jahrbuch für Mineralogie Monatshefte, 545–551.Google Scholar
Barker, C. & Sommer, M.A. (1973) Mass spectrometric analysis of the volatiles released by heating or crushing rocks. American Society of Testing Materials, Special Technical Publication, 539, 56–70.Google Scholar
Beck, C.W. (1950) Differential thermal analysis curves of carbonate minerals. American Mineralogist, 35, 1006–1007.Google Scholar
Bellotto, M., Rebours, B., Clause, O., Lynch, J., Bazin, D. & Elkaim, E. (1996) Hydrotalcite decomposition mechanism: A clue to the structure and reactivity of spinel-like mixed oxides. Journal of Physical Chemistry, 100, 8535–8542.Google Scholar
Bera, P., Rajamathi, M., Hegde, M.S. & Kamath, P.V. (2000) Thermal behaviour of hydroxides, hydroxysalts and hydrotalcites. Bulletin of Materials Science, Indian Academy of Science, 23, 141–145.Google Scholar
Cavani, F., Trifiro, F. & Vaccari, A. (1991) Hydrotalcitetype anionic clays: preparation, properties and applications. Catalysis Today, 11, 173–301.CrossRefGoogle Scholar
Constantino, V.R.L. & Pinnavaia, T.J. (1995) Basic properties of Mg2+ 1-xAl3+ x layered double hydroxides intercalated carbonate, hydroxide, chloride, and sulphate anions. InorganicChemistry, 34, 883–892.Google Scholar
Derouane, E.g., Jullien-Ladrot, V., Davis, R.J., Blom, N. & Hojlund-Nielsen, P.E. (1993) Aromatization of n-hexane by aluminium-stabilized magnesium oxide-supported noble metal catalysts. Pp. 1031–1042 in: New Frontiers in Catalysis (Guczi, L. et al., editors). Elsevier Science Publishers, Amsterdam, The Netherlands.Google Scholar
Frueh, A.J. & Golightly, J.P. (1967) The crystal structure of dawsonite NaAl(CO3)(OH)2 . The Canadian Mineralogist, 10, 51–56.Google Scholar
Hibino, T., Yamashita, Y., Kosuge, K. & Tsunashima, A. (1995) Decarbonation behaviour of Mg-Al-CO3 hydrotalcite-like compounds during heat treatment. Clays and Clay Minerals, 43, 427–432.Google Scholar
Kanezaki, E. (1998) Thermal behavior of the hydrotalcite-like layered structure of Mg and Al-layered double hydroxides with interlayer carbonate by means of in situ powder HTXRD and DTA/TG. Solid State Ionics, 106, 279–284.CrossRefGoogle Scholar
Lanphere, M. & Dalrymple, G. (1966) Simplified bulb tracer system for argon analyses. Nature, 209, 902–903.Google Scholar
Malherbe, F. & Besse, J.P. (2000) Investigating the effects of guest-host interaction on the properties of anion-exchanged Mg-Al hydrotalcites. Journal of Solid State Chemistry, 155, 332–341.Google Scholar
Miyata, S. (1980) Physico-chemical properties of synthetic hydrotalcites in relation to composition. Clays and Clay Minerals, 28, 50–56.CrossRefGoogle Scholar
Miyata, S. (1983) Anion-exchange properties of hydrotalcite- like compounds. Clays and Clay Minerals, 31, 305–311.CrossRefGoogle Scholar
Musselman, L.L. & Green, H.L. (1996) Materials for use as fire retardant additives. US Patent 5,480,587. Google Scholar
Newman, S.P. & Jones, W. (1998) Synthesis, characterization and application of layered double hydroxides containing organic guests. New Journal of Chemistry, 105-115.Google Scholar
Petrova, N., Mizota, T., Stanimirova, Ts. & Kirov, G. (2003) Sorption of water vapor on a low-temperature hydrotalcite metaphase: a calorimetric study. Microporous and Mesoporous Matarials, 63, 139–145.Google Scholar
Reichle, W.T., Kang, S.Y. & Everhardt, D.S. (1986) The nature of thermal decomposition of a catalytically active anionic clay minerals. Journal of Catalysis, 101, 352–359.Google Scholar
Rey, F. & Fornes, V. (1992) Thermal decomposition of hydrotalcites. Journal of the Chemical Society, Faraday Transactions, 88, 2233–2238.Google Scholar
Rives, V. (1999) Comment on ‘Direct observation of metastable solid state phase of Mg/Al/CO3-layered double hydroxides by means of high-temperature in situ powder XRD and DTA/TG. Inorganic Chemistry, 38, 406–407.Google Scholar
Roelofs, J., van Bokhoven, J.A., van Dillen, A.J., Geus, J. & de Jong, K. (2002) The thermal decomposition of Mg-Al hydrotalcites: Effect of interlayer anions and characteristics of the final structure. Chemical European Journal, 8, 5571–5579.3.0.CO;2-R>CrossRefGoogle ScholarPubMed
Sato, T., Fujita, H., Endo, T., Shimada, M. & Tsunashima, A. (1988) Synthesis of hydrotalcite-like compounds and their physico-chemical properties. Reactivity of Solids, 5, 219–228.CrossRefGoogle Scholar
Stanimirova, Ts. & Petrova, N. (1999) DTA and TG study of minerals from the hydrotalcite-takovite isomorphic series: II influence of M2+/M3+ ratio. Comptes Rendus de l'Academie Bulgare des Sciences, 52, 59–62.Google Scholar
Stanimirova, Ts., Vergilov, I., Kirov, G. & Petrova, N. (1999) Thermal decomposition products of hydrotalcite-like compounds: low-temperature metaphases. Journal of Materials Science, 34, 4153–4161.Google Scholar
Stanimirova, Ts. (2001) Hydrotalcite polytypes from Snarum, Norway. Annual of the University of Sofia, Faculty of Geology, 94, 73–78.Google Scholar
Su, C. & Suares, D.L. (1997) In situ infrared speciation of adsorbed carbonate on aluminum and iron oxides. Clays and Clay Minerals, 45, 814–825.CrossRefGoogle Scholar
Ulibarri, M.A., Pavlovic, I., Barriga C, Hermosin, M.C. & Cornejo, J. (2001) Adsorption of anionic species on hydrotalcite-like compounds: effect of interlayer anion and cristallinity. Applied Clay Science, 18, 17–27.Google Scholar
Vaccari, A. (1998) Preparation and catalytic properties of cationic and anionic clays. Catalysis Today, 41, 1–3, 53–71.Google Scholar
van Bokhoven, J.A., Roelofs, J., de Jong, K.P. & Koningsberger, D.C. (2001) Unique structural properties of the Mg-Al hydrotalcite solid base catalyst: An in situ study using Mg and Al K-edge XAFS during calcination and rehydration. Chemical European Journal, 7, 1258–1265.Google Scholar
Vaysse, C., Guerlou-Demourgues, L. & Delmas, C. (2002) Thermal evolution of carbonate pillared layered double hydroxides with (Ni, L) (L=Fe, Co) based slabs: grafting or nongrafting of carbonate anions. InorganicChemistry, 41, 6905–6913.Google Scholar
Wang, J., Kalinichev, A.G., Kirkpatrick, R.J. & Hou, X. (2001) Molecular modeling of the structure and energetics of hydrotalcite hydration. Chemistry of Materials, 13, 145–150.Google Scholar
White, W.B. (1974) Carbonate minerals. Pp. 224–284 in: The Infrared Spectra of Minerals (Farmer, V.C., editor). Monograph 4, Mineralogical Society, London.Google Scholar
Xu, Z.P. & Zeng, H.C. (2001) Abrupt structural transformation in hydrotalcite-like compounds Mg1-xAlx(OH)2(NO3)xnH2O as a continuous function of nitrate anions. Journal of Physical Chemistry, B, 105, 1743–1749.Google Scholar