Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-10T07:01:40.276Z Has data issue: false hasContentIssue false

Solid-State Nuclear Magnetic Resonance Study of Sepiolite and Partially Dehydrated Sepiolite

Published online by Cambridge University Press:  01 January 2024

Mark R. Weir
Affiliation:
Ottawa-Carleton Chemistry Institute, Department of Chemistry, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5
Wenxing Kuang
Affiliation:
Ottawa-Carleton Chemistry Institute, Department of Chemistry, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5
Glenn A. Facey
Affiliation:
Ottawa-Carleton Chemistry Institute, Department of Chemistry, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5
Christian Detellier*
Affiliation:
Ottawa-Carleton Chemistry Institute, Department of Chemistry, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5
*
*E-mail address of corresponding author: dete@science.uottawa.ca
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.

The assignment of the 29Si CP/MAS-NMR spectrum of naturally-occurring sepiolite clay was re-examined using 29Si COSY and 1H-29Si HETCOR pulse sequences. Each of the three main resonances at −92.1, −94.6 and −98.4 ppm has been attributed to one of the three pairs of equivalent Si nuclei in the basal plane, and the resonance at −85 ppm to Q2(Si-OH) Si nuclei. On the basis of the COSY experiment, the resonance at −92.1 ppm is unambiguously assigned to the intermediate, near-edge Si sites. The HETCOR experiment revealed that the resonance at −94.6 ppm cross-polarizes almost entirely from the Mg-OH protons, and therefore is assigned to the central Si position. The remaining resonance at −98.4 ppm correlates strongly to the protons of the structural water molecules and therefore is assigned to the edge Si sites. Nearly complete rehydration was achieved at room temperature by exposing sepiolite samples that had been partially dehydrated at 120°C to water vapor or to D2O vapor. The rehydration results support the 29Si NMR peak assignments that were made on the basis of the COSY and HETCOR experiments.

The 29Si CP/MAS-NMR spectrum corresponding to the folded sepiolite structure in which approximately one half of the structural water has been removed by heating to 350°C is reported for the first time. The chemical shift values and relative intensities are significantly different compared to the resonances that are observed in the corresponding spectrum of the true sepiolite anhydride. These observations support the earlier claim that sepiolite heated to ∼350°C exists as a distinct phase to be differentiated from that of the completely dehydrated state.

Type
Research Article
Copyright
Copyright © 2002, The Clay Minerals Society

References

Aramendía, M.A. Jiménez, V.B.C. Marinas, J.M. and Ruiz, J.R., (1997) Characterization of Spanish sepiolites by high-resolution solid-state NMR Solid State Nuclear Magnetic Resonance 8 251256 10.1016/S0926-2040(97)00009-X.CrossRefGoogle ScholarPubMed
Barron, P.F. and Frost, R.L., (1985) Solid-state 29Si NMR examination of the 2:1 ribbon magnesium silicates, sepiolite and palygorskite American Mineralogist 70 758 766.Google Scholar
Corma, A. and Martín-Aranda, R.M., (1991) Alkaline-substituted sepiolites as a new type of strong base catalyst Journal of Catalysis 130 130137 10.1016/0021-9517(91)90097-N.CrossRefGoogle Scholar
Damyanova, S. Daza, L. and Fierro, J.L.G., (1996) Surface and catalytic properties of lanthanum-promoted Ni/sepiolite catalysts for styrene hydrogenation Journal of Catalysis 159 150161 10.1006/jcat.1996.0074.CrossRefGoogle Scholar
Demirci, S., Erdogan, B. and Akay, Y. (1995) Removal of turbidity and color of sugar juices by using some Turkish bentonites and sepiolite. Proceedings Euroclay’ 95, Leuven, Belgium, pp. 158159.Google Scholar
d’Espinose de la Caillerie, J.-B. and Fripiat, J.J., (1992) Almodified sepiolite as catalyst or catalyst support Catalysis Today 14 125140 10.1016/0920-5861(92)80017-H.CrossRefGoogle Scholar
d’Espinose de la Caillerie, J.-B. and Fripiat, J.J., (1994) A reassessment of the 29Si MAS-NMR spectra of sepiolite and aluminated sepiolite Clay Minerals 29 313318 10.1180/claymin.1994.029.3.02.CrossRefGoogle Scholar
Galan, E., (1996) Properties and applications of palygorskitesepiolite clays Clay Minerals 31 443453 10.1180/claymin.1996.031.4.01.CrossRefGoogle Scholar
Inagaki, S. Fukushima, Y. Doi, H. and Kamigaito, O., (1990) Pore size distribution and adsorption selectivity of sepiolite Clay Minerals 25 99105 10.1180/claymin.1990.025.1.11.CrossRefGoogle Scholar
Jiménez-López, A. López-González, J. Ramírez-Saenz, A. Rodríguez-Reinoso, F. Valenzuela-Calahorro, C. and Zurita-Herrera, L., (1978) Evolution of surface area in a sepiolite as a function of acid and heat treatments Clay Minerals 13 375385 10.1180/claymin.1978.013.4.03.CrossRefGoogle Scholar
Komarneni, S. Fyfe, C.A. and Kennedy, G.J., (1986) Detection of nonequivalent Si sites in sepiolite and palygorskite by solid-state 29Si Magic Angle Spinning-Nuclear Magnetic Resonance Clays and Clay Minerals 34 99102 10.1346/CCMN.1986.0340113.CrossRefGoogle Scholar
Le Van Mao, R. Rutinduka, E. Detellier, C. Gougay, P. Hascoet, V. Tavakoliyan, S. Hoa, S.V. and Matsuura, T., (1999) Mechanical and pore characteristics of zeolite composite membranes Journal of Materials Chemistry 9 783788 10.1039/a806624h.Google Scholar
Myriam, M. Suárez, M. and Martín-Pozas, J.M., (1998) Structural and textural modifications of palygorskite and sepiolite under acid treatment Clays and Clay Minerals 46 225231 10.1346/CCMN.1998.0460301.CrossRefGoogle Scholar
Nagata, H. Shimoda, S. and Toshio, S., (1974) On dehydration of bound water of sepiolite Clays and Clay Minerals 22 285293 10.1346/CCMN.1974.0220310.CrossRefGoogle Scholar
Pérez-Rodríguez, J.L. and Galán, E., (1994) Determination of impurity in sepiolite by thermal analysis Journal of Thermal Analysis 42 131141 10.1007/BF02546996.CrossRefGoogle Scholar
Preisinger, A., (1959) X-ray study of the structure of sepiolite Clays and Clay Minerals 6 6167 10.1346/CCMN.1957.0060106.CrossRefGoogle Scholar
Preisinger, A., (1963) Sepiolite and related compounds: its stability and application Clays and Clay Minerals 10 365371 10.1346/CCMN.1961.0100132.CrossRefGoogle Scholar
Rytwo, G. Nir, S. Margulies, L. Casal, B. Merino, J. Ruiz-Hitzky, E. and Serratosa, J., (1998) Adsorption of monovalent organic cations on sepiolite: experimental results and model calculations Clays and Clay Minerals 46 340348 10.1346/CCMN.1998.0460313.CrossRefGoogle Scholar
Serna, C. Ahlrichs, J.L. and Serratosa, J.M., (1975) Folding in sepiolite crystals Clays and Clay Minerals 23 452457 10.1346/CCMN.1975.0230607.CrossRefGoogle Scholar
Shariatmadari, H. Mermut, A.R. and Benke, M.B., (1999) Sorption of selected cationic and neutral organic molecules on palygorskite and sepiolite Clays and Clay Minerals 47 4453 10.1346/CCMN.1999.0470105.CrossRefGoogle Scholar
Shore, J.S. De Paul, S. Ernst, M. Phillips, B.L. and Fitzgerald, J.J., (1998) Double-Resonance and Two-Dimensional Silicon-29 NMR Spectroscopy of Minerals Solid-State Nuclear Magnetic Resonance of Inorganic Materials Washington, D.C. American Chemical Society 305 325.Google Scholar
Sugiura, M., (1993) Removal of methanethiol by sepiolite and various sepiolite-metal compound complexes in ambient air Clay Science 9 33 41.Google Scholar
Sugiura, M., Horii, M., Hayashi, H., Suzuki, T., Kamigaito, O., Nogawa, S. and Oishi, S. (1990) Deodorizing paper using β-sepiolite. Pp. 91100 in: Proceedings of the 9th International Clay Conference, Strasbourg, France.Google Scholar
Sugiura, M. Fukumoto, K. and Inagaki, S., (1991) Adsorption of odorous vapours by sepiolite in ambient air Clay Science 8 129 145.Google Scholar
Vincente, M.A. López-González, J.D. and Bañares, M.A., (1994) Acid activation of a Spanish sepiolite: physicochemical characterization, free silica content and surface area of products obtained Clay Minerals 29 361367 10.1180/claymin.1994.029.3.07.Google Scholar
Wang, Q.K. Matsuura, T. Feng, C.Y. Weir, M.R. Detellier, C. Rutinduka, E. and Le Van Mao, R., (2001) The sepiolite membrane for ultrafiltration Journal of Membrane Science 184 153163 10.1016/S0376-7388(00)00605-0.CrossRefGoogle Scholar
Weir, M.R., Facey, G.A. and Detellier, C. (2000) 1H, 2H, and 29Si solid state NMR study of guest acetone molecules occupying the zeolitic channels of partially dehydrated sepiolite clay. Studies in Surface Science and Catalysis (Sayari, A. et al., editors), 129, 551558.CrossRefGoogle Scholar
Weir, M.R. Rutinduka, E. Detellier, C. Feng, C.Y. Wang, Q. Matsuura, T. and Le Van Mao, R., (2001) Fabrication, characterization and preliminary testing of all-inorganic ultrafiltration membranes composed entirely of a naturally occurring sepiolite clay mineral Journal of Membrane Science 182 4150 10.1016/S0376-7388(00)00547-0.CrossRefGoogle Scholar