Inorganic Materials

, Volume 43, Issue 7, pp 758–769

A study of the chemistry of isomorphous substitution and characterization of Al-ZSM-5 and Sc-ZSM-5 synthesized in fluoride media

  • Cl. T. Briden
  • C. D. Williams
  • D. Apperley
Article

Abstract

Al-ZSM-5 and Sc-ZSM-5 samples have been synthesized using fluoride media at around neutral pH. The synthesis chemistry has been studied and it is shown how the lower tendency of scandium to undergo increased fluoro-complexation (compared with aluminum) coupled with its tendency to hydrolyze is conductive to its isomorphous substitution and framework incorporation into the MFI zeolite structure. Clear unit cell volume expansion, elongation of the c crystallographic axis with increased scandium content, and a strong positive linear correlation between the unit cell volume expansion and the calculated unit cell framework scandium content are shown. Chemical shifts are assigned to tetrahedral and octahedral scandium from 45Sc MAS NMR analysis. Shoulders and a peak at lower wavenumber on the main internal T-O asymmetric stretches in the FT-IR spectra indicate that an interaction exists between framework-incorporated scandium and the SiO4 tetrahedra. It is concluded from the experimental evidence that isomorphous substitution of scandium into the zeolite framework has been achieved.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Barrer, R.M., Hydrothermal Chemistry of Zeolites, London: Academic, 1982, p. 251.Google Scholar
  2. 2.
    Ratnasamy, P., Isomorphous Substitution in Zeolites—Structural and Catalytic Consequences, React. Kinet. Catal. Lett., 1987, vol. 35, nos. 1–2, pp. 219–226.CrossRefGoogle Scholar
  3. 3.
    Goldsmith, J.R., Min. Mag, 1952, vol. 29, p. 952.CrossRefGoogle Scholar
  4. 4.
    Dwyer, J., Zhao, J., and Rawlence, D., Synthesis of NH4-Form Heteroatom-Substituted MFI Zeolites in the Presence of Fluoride Anions, Proc. of the 9th Int. Zeolite Conf., Montreal: Butterworth-Heinemann, 1992, pp. 155–162.Google Scholar
  5. 5.
    Testa, F., Chiappetta, R., Crea, F., et al., Synthesis of Borosilicate-1 with High Boron Content from Fluoride Containing Media, Stud. Surf. Sci. Catal., 1995, vol. 94, pp. 349–356.Google Scholar
  6. 6.
    Aiello, R., Crea, F., Nigro, E., et al., The Influence of Alkali Cations on the Synthesis of ZSM-5 in Fluoride Medium, Microporous Mesoporous Mater., 1999, vol. 28, pp. 241–259.CrossRefGoogle Scholar
  7. 7.
    Nigro, E., Crea, F., Testa, F., et al., The Role of Alkali Cations in the Synthesis of Ga-ZSM-5 in Fluoride Medium, Microporous and Mesoporous Mater., 1999, vol. 30, pp. 199–211.CrossRefGoogle Scholar
  8. 8.
    Bull, I., Young, V., Teat, S.J., et al., Hydrothermal Synthesis and Structural Characterization of Four Scandium Phosphate Frameworks, Chem. Mater., 2003, vol. 15, pp. 3818–3825.CrossRefGoogle Scholar
  9. 9.
    Bull, L., Wheatley, P.S., Lightfoot, P., et al., Synthesis and Crystal Structure of the First Scandium-Containing Open Framework Solid, Chem. Commun., 2002, vol. 11, pp. 1180–1181.CrossRefGoogle Scholar
  10. 10.
    Riou, D., Fayon, F., and Massiot, D., Hydrothermal Synthesis, Structure Determination, and Solid-State NMR Study of the First Organically Templated Scandium Phosphate, Chem. Mater., 2002, vol. 14, no. 5, pp. 2416–2420.CrossRefGoogle Scholar
  11. 11.
    Brigden, C.T., Thompsett, D., and Williams, C., Preparation of Isomorphously Substituted Scandium ZSM-5 Using Aqueous Fluoride Gels, Dalton Trans., 2004, vol. 18, pp. 2829–2830.CrossRefGoogle Scholar
  12. 12.
    Gschneidner, K.A., Jr., Melson, G.A., Youngblood, D.H., and Schock, H.H., Scandium: Its Occurrence, Chemistry, Physics, Metallurgy, Biology and Technology, Horovitz, C.T., Ed., London: Academic, 1975, pp. 6, 111–112, 124–125, 156, 443.Google Scholar
  13. 13.
    Tavolaro, A., Mostowicz, R., Crea, F., et al., Formation of MFI Crystalline Zeosilites from Fluoride-Containing Silicate Gels, Appl. Spectrosc., 1992, vol. 12, no. 6, pp. 756–761.Google Scholar
  14. 14.
    Axon, S.A. and Klinowski, J., Nuclear-Magnetic-Resonance Studies of the Synthesis of Zeolite ZSM-5 by the Fluoride Method, Appl. Catal., A, 1994, vol. 111, no. 1, pp. 29–39.CrossRefGoogle Scholar
  15. 15.
    Round, C.I., Williams, C.D., Latham, K., and Duke, C.V.A., Ni-ZSM-5 and Cu-ZSM-5 Synthesized Directly from Aqueous Fluoride Gels, Chem. Mater., 2001, vol. 13, pp. 468–472.CrossRefGoogle Scholar
  16. 16.
    Singh, R. and Dutta, P.K., Handbook of Zeolite Technology, Auerbach, S.M. et al., Eds., New York: Marcel Dekker, 2003, p. 34.Google Scholar
  17. 17.
    Baerlocher, C., Meier, W.M., and Olson, D.H., Atlas of Zeolite Framework Types, Amsterdam: Elsevier, 2001, 5th ed., p. 184.Google Scholar
  18. 18.
    Nigro, E., Mostowicz, R., Crea, F., et al., Synthesis and Characterization of ZSM-5 in Fluoride Medium: The Role of NH4+ and K+ Cations, Stud. Surf. Sci. Catal., 1997, vol. 105, pp. 309–316.CrossRefGoogle Scholar
  19. 19.
    Sur, S.K. and Bryant, R.G., 19F & 27Al NMR Spectroscopic Study of the Fluoro Complexes of Aluminium in Aqueous Solution & in Zeolites: Dealumination of Zeolites by Fluoride Ion, Appl. Spectrosc., 1996, vol. 16, nos. 2–3, pp. 118–124.Google Scholar
  20. 20.
    Greenwood, N.N. and Earnshaw, A., Chemistry of the Elements, Oxford: Pergamon, 1984, pp. 254–255, 267, 1105–1107.Google Scholar
  21. 21.
    Ivanov-Emin, B.N., Susanina, T.N., and Ogorodnikova, L.A., Zh. Neorg. Khim., 1966, vol. 11, pp. 504–510.Google Scholar
  22. 22.
    Tananaev, I.V. and Golubev, O.F., Izv. Akad. Nauk SSSR. Neorg. Mater., 1966, vol. 2, no. 6, pp. 1097–1104.Google Scholar
  23. 23.
    Tananaev, I.V. and Golubev, O.F., Izv. Akad. Nauk SSSR, Neorg. Mater., 1966, vol. 2, no. 8, pp. 1403–1409.Google Scholar
  24. 24.
    Tananaev, I.V. and Golubev, O., F, Izv. Akad. Nauk. SSSR, Neorg. Mater., 1969, vol. 5, no. 9, pp. 1552–1557.Google Scholar
  25. 25.
    Kury, J.W., Paul, A.D., Hepler, L.G., and Connick, R.E., J. Am. Chem. Soc., 1959, vol. 81, pp. 4185–4189.CrossRefGoogle Scholar
  26. 26.
    Baes, C.F., Jr. and Mesmer, R.E., The Hydrolysis of Cations, Wiley-Interscience, 1976, p. 123.Google Scholar
  27. 27.
    Ivanov-Emin, B.N. and Ostroumov, E.A., J. Gen. Chem. USSR, 1944, vol. 14, pp. 772–776.Google Scholar
  28. 28.
    http://nmr.ioc.ac.runmric/b2p.htm (updated on 29th August, 1998, accessed on 7th June, 2004).
  29. 29.
    Scarano, D., Zecchina, A., Bordiga, S., et al., Fourier-Transform Infrared and Raman Spectra of Pure and Al-, B-, Ti-, and Fe-Substituted Silicalites: Stretching-Mode Region, J. Chem. Soc., Faraday Trans., 1993, vol. 89, no. 22, pp. 4123–4130.CrossRefGoogle Scholar

Copyright information

© Pleiades Publishing, Inc. 2007

Authors and Affiliations

  • Cl. T. Briden
    • 1
  • C. D. Williams
    • 1
  • D. Apperley
    • 2
  1. 1.School of Applied SciencesUniversity of WolverhamptonWolverhamptonUK
  2. 2.Department of ChemistryDurham UniversityDurhamUK

Personalised recommendations