Hostname: page-component-848d4c4894-x24gv Total loading time: 0 Render date: 2024-06-03T00:11:36.129Z Has data issue: false hasContentIssue false

Enhanced Thermal Stability of Al-Pillared Smectites Modified with Ce and La

Published online by Cambridge University Press:  28 February 2024

J. L. Valverde*
Affiliation:
Chemical Engineering Department, Faculty of Chemistry, University of Castilla-La Mancha, Campus Universitario s/n., 13004, Ciudad Real, Spain
P. Cañizares
Affiliation:
Chemical Engineering Department, Faculty of Chemistry, University of Castilla-La Mancha, Campus Universitario s/n., 13004, Ciudad Real, Spain
M. R. Sun Kou
Affiliation:
Chemical Engineering Department, Faculty of Chemistry, University of Castilla-La Mancha, Campus Universitario s/n., 13004, Ciudad Real, Spain Chemical Department, Faculty of Science and Engineering, Pontificia University Catholic of Peru, Av. Universitaria, Cuadra 18, San Miguel, Lima 100, Perú
C. B. Molina
Affiliation:
Chemical Engineering Department, Faculty of Chemistry, University of Castilla-La Mancha, Campus Universitario s/n., 13004, Ciudad Real, Spain
*
E-mail of corresponding author: jlvalver@inqu-cr.uclm.es

Abstract

A commercial bentonite (primarily smectite) from Fischer Scientific Company (F bentonite) and a natural bentonite from Peru (P bentonite) were used in the preparation of pillared clays with polyoxymetal cations of Al that were subsequently modified with Ce and La. Several Al/metal ratios (5 and 9) were used to investigate the effects on the thermal and hydrothermal stability of these synthetic clays. The structure of these materials was studied by X-ray diffraction. Isotherms were determined by N2 adsorption. Thermal stability was determined using thermogravimetric (TG) measurements and ara-monia-TPD (temperature programmed desorption) was used to obtain acidity data. These materials exhibited basal spacings from 16 to 20 Å, with surface areas from 239 to 347 m2g−1, with microporosity contributing from 50 to 80% of the total surface area. Pillared clays prepared from F bentonite generally showed larger basal spacings and surface areas than those prepared from P bentonite. Pillared clays modified with Ce or La did not show any apparent structural changes relative to the Al-pillared clays. Pillared clays modified with Ce and La had similar acid properties as Al-pillared clays. In contrast, the thermal and hydrothermal stabilities of these materials were greater than Al-pillared clays. However, Ce-pillared clay appears to be more effective than La-pillared clay in delaying the dehydroxylation of pillared clays with increasing temperature. The intercalation of Ce and La into Al-pillared clays improved the thermal stability, which may increase the utility of these materials as catalysts.

Type
Research Article
Copyright
Copyright © 2000, The Clay Minerals Society

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

Barret, E.P. Joyner, L.G. and Halenda, P.P., 1951 The determination of pore volume and area distribution in porous substances. I. Computations from nitrogen isotherms Journal of the American Chemical Society 73 373380 10.1021/ja01145a126.CrossRefGoogle Scholar
Bartley, G.J.J. and Burch, R., 1985 Zr-containing pillared interlayer clays. Part III. Influence of method of preparation on the thermal and hydrofhermal stability Applied Catalysis 19 175185 10.1016/S0166-9834(00)82679-2.CrossRefGoogle Scholar
Bergaya, E. Hassoun, N. Barrault, J. and Gatineau, L., 1993 Pillaring of synthetic hectorite by mixed (Al13−x Fex) pillars Clays and Clay Minerals 28 109122 10.1180/claymin.1993.028.1.10.CrossRefGoogle Scholar
Burch, R. and Warburton, C.I., 1986 Zr-containing pillared interlayer clays. I. Preparation and structural characterization Journal of Catalysis 97 503510 10.1016/0021-9517(86)90021-7.CrossRefGoogle Scholar
Burch, R. and Warburton, C.I., 1987 Pillared clays as de-metallisation catalysts Applied Catalysis 33 395404 10.1016/S0166-9834(00)83070-5.CrossRefGoogle Scholar
Canizares, P. Valverde, JL S Kou, M.R. and Molina, C.B., 1999 Synthesis and characterization of PILCs with single and mixed oxide pillars prepared from two different bentonites. A comparative study Microporous and Mesoporous Materials 29 267281 10.1016/S1387-1811(98)00295-9.CrossRefGoogle Scholar
Carrado, K.A. Suib, S.L. Skoularikis, N.D. and Coughlin, R.W., 1986 Chromium (III)-doped pillared clays (PILCs) Inorganic Chemistry 25 42174221 10.1021/ic00243a031.CrossRefGoogle Scholar
Fetter, G. Tichit, D. de Menorval, L.C. and Figueras, F., 1995 Synthesis and characterization of pillared clays containing both Si and Al pillars Applied Catalysis A: General 126 165176 10.1016/0926-860X(95)00030-5.CrossRefGoogle Scholar
Gil, A. and Montes, M., 1994 Analysis of the microporosity in pillared clays Langmuir 10 291297 10.1021/la00013a043.CrossRefGoogle Scholar
Gil, A. and Montes, M., 1997 Metathesis of propene on molybdenum-alumina-pillared montmorillonite Industrial & Engineering Chemistry Research 36 14311443 10.1021/ie960578a.CrossRefGoogle Scholar
Gregg, S.J. and Sing, K.S.W., 1991 Adsorption, Surface Area and Porosity London Academic Press 139.Google Scholar
Hernando, M.J. Pesquera, C. Blanco, C. Benito, I. and Gonzalez, F., 1996 Effect of Ce on catalytic properties of pillared montmorillonite with Al- and GaAl-polyoxocations Applied Catalysis A: General 141 175183 10.1016/0926-860X(96)00035-X.CrossRefGoogle Scholar
Horvath, G. and Kawazoe, K., 1983 Method for the calculation of effective pore size distribution in molecular sieve carbon Journal of Chemical Engineering of Japan 16 470475 10.1252/jcej.16.470.CrossRefGoogle Scholar
Lee, W.Y. Raythatha, R.H. and Tatarchuck, B.J., 1989 Pillared-clay catalysts containing mixed-metal complexes Journal of Catalysis 115 159179 10.1016/0021-9517(89)90016-X.CrossRefGoogle Scholar
Lou, C. and Huang, P.M., 1988 Hydroxy-aluminosilicate interlayers in montmorillonite: Implications for acidic environments Nature 335 625627 10.1038/335625a0.CrossRefGoogle Scholar
Masters, K.J. and McEnaney, B., 1983 Structural analysis of microporous carbons using the Dubinin-Radushkevich equation Journal of Colloid Interface Science 95 340352 10.1016/0021-9797(83)90193-5.CrossRefGoogle Scholar
Miller, S.E. Heath, G.R. and Gonzalez, R.D., 1982 Effects of temperature on the sorption of lanthanides by montmorillonite Clays and Clay Minerals 30 111122 10.1346/CCMN.1982.0300205.CrossRefGoogle Scholar
Monkaya, R. and Jones, W., 1995 Pillared clays and pillared acid-activated clays: A comparative study of physical, acidic and catalytic properties Journal of Catalysis 153 7685 10.1006/jcat.1995.1109.CrossRefGoogle Scholar
Oades, J.M., 1984 Interactions of polycations of aluminum and iron with clays Clays and Clay Minerals 32 4957 10.1346/CCMN.1984.0320107.CrossRefGoogle Scholar
Occelli, M.L., 1986 New routes to the preparation of pillared montmorillonite catalysts Journal of Molecular Catalysis 35 377389 10.1016/0304-5102(86)87085-7.CrossRefGoogle Scholar
Occelli, M.L. and Tindwa, R.M., 1983 Physicochemical properties of montmorillonite interlayered with cationic oxyaluminum pillars Clays and Clay Minerals 31 2228 10.1346/CCMN.1983.0310104.CrossRefGoogle Scholar
Pinnavaia, T.J. Tzou, M. Landau, S.D. and Raythatha, R.H., 1984 On the pillaring and delamination of smectite clay catalysts by polyoxocations of aluminum Journal of Molecular Catalysis 27 195212 10.1016/0304-5102(84)85080-4.CrossRefGoogle Scholar
Pinnavaia, T.J. Tzou, M. and Landau, S.D., 1985 New chromia pillared clay catalysts Journal of the American Chemical Society 107 47834785 10.1021/ja00302a033.CrossRefGoogle Scholar
Poyato, J. Tobias, M.M. and Trillo, J.M., 1987 Retention of La(III) and Nd(III) by montmorillonite Inorganic Chimica Acta 14 307308 10.1016/S0020-1693(00)81111-1.CrossRefGoogle Scholar
Rodríguez-Reinoso, F. Garrido, J. Martín-Martinez, J.M. Molina-Sabio, M. and Torregrosa, R., 1989 The combined use of different approaches in the characterization of microporous carbons Carbon 27 2332 10.1016/0008-6223(89)90153-X.CrossRefGoogle Scholar
Safdar Baksh, M. Kikkinides, E.S. and Yang, R.T., 1992 Characterization by physisorption of a new class of microporous adsorbents: Pillared clays Industrial & Engineering Chemistry Research 31 21812189 10.1021/ie00009a016.CrossRefGoogle Scholar
Schoonheydt, R.A. Van den Eynde, J. Tubbax, H. Leeman, H. Stuyckens, M. Lenotte, I. and Stone, W.E.E., 1993 The Al pillaring of clays. Part I. Pillaring with dilute and concentrated Al solutions Clays and Clay Minerals 41 598607 10.1346/CCMN.1993.0410510.CrossRefGoogle Scholar
Shabtai, J. Rosell, M. and Tokarz, M., 1984 Cross-linked smectites. III. Synthesis and properties of hydroxy-aluminum hectorites and fluorhectorites Clays and Clay Minerals 32 99107 10.1346/CCMN.1984.0320203.CrossRefGoogle Scholar
Shen, Y.F., 1990 Study of phosphorus-modified aluminum pillared montmorillonite I. Effect of the nature of phosphorus compounds Applied Catalysis 67 93106 10.1016/S0166-9834(00)84434-6.CrossRefGoogle Scholar
Sterte, J.P., 1986 Preparation and properties of titanium oxide cross-linked montmorillonite Clays and Clay Minerals 34 658664 10.1346/CCMN.1986.0340606.CrossRefGoogle Scholar
Sterte, J.P., 1991 Preparation and properties of large-pore lanthanum-aluminum-pillared montmorillonite Clays and Clay Minerals 39 167173 10.1346/CCMN.1991.0390208.CrossRefGoogle Scholar
Stubican, V. and Roy, R., 1961 A new approach to assignment of infrared absorption bands in layer-structure silicates Zeitschrift für Kristallographie 115 200214 10.1524/zkri.1961.115.3-4.200.CrossRefGoogle Scholar
Suzuki, K. Horio, M. and Mori, T., 1988 Preparation of alumina-pillared montmorillonite with desired pillar population Material Research Bulletin 23 17111718 10.1016/0025-5408(88)90180-8.CrossRefGoogle Scholar
Tennakoon, D.T.B. Carpenter, T.A. Jones, W. and Thomas, J.M., 1986 Characterization of clays and clay-organic systems. Cation diffusion and dehydroxylation Journal of the Chemical Society, Faraday Transactions 1 82 545562 10.1039/f19868200545.CrossRefGoogle Scholar
Tichit, E. Fajula, F. Figueras, F. Ducourant, B. Mascherpa, G. Gueguen, C. and Bousquet, J., 1988 Sintering of montmorillonites pillared by hydroxy-aluminum species Clays and Clay Minerals 36 369375 10.1346/CCMN.1988.0360413.CrossRefGoogle Scholar
Tokarz, M. and Shabtai, J., 1985 Cross-linked smectites. IV. Preparation and properties of hydroxyaluminium-pillared cerium- and lanfhanum-montmorillonites and fluorinated ammonium ion-montmorillonites Clays and Clay Minerals 33 8998 10.1346/CCMN.1985.0330202.CrossRefGoogle Scholar
Vaughan, D.E.W., 1987 Multimetallic pillared interlayered clay products and processes of making them .Google Scholar
Viera Coelho, A. and Poncelet, G., 1991 Gallium, aluminum and mixed gallium-aluminum pillared montmorillonite. Preparation and characterization Applied Catalysis 77 303314 10.1016/0166-9834(91)80073-6.CrossRefGoogle Scholar
Yamanaka, S. and Hattori, M., 1988 Iron oxide pillared clay Catalysis Today 2 261270 10.1016/0920-5861(88)85008-9.CrossRefGoogle Scholar
Yang, R.T. and Baksh, M.S.A., 1991 Pillared clays as a new class of sorbents for gas separation American Institute of Chemical Engineering Journal 37 679686 10.1002/aic.690370506.CrossRefGoogle Scholar