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Journal of Chemical Sciences

, Volume 112, Issue 4, pp 439–448 | Cite as

Isomorphous substitution of Mn(II), Ni(II) and Zn(II) in AlPO-31 molecular sieves and study of their catalytic performance

  • V. Umamaheswari
  • C. Kannan
  • Banumathi Arabindoo
  • M. Palanichamy
  • V. Murugesan
Article

Abstract

Isomorphously substituted molecular sieves, MAPO-31, NAPO-31 and ZAPO-31, were prepared under mild hydrothermal conditions from gels containing sources of aluminium, phosphorus, appropriate metal and dipropylamine (DPA), presumably acting as a structure-directing template. They were characterized by XRD, FTIR, TGA, inductively coupled plasma (ICP), ESR, Brunauer, Emmett, Teller (BET) and diffusion reflectance spectroscopy (DRS) techniques. In the XRD, the peak at 2θ = 16.7° of the metal substituted AlPO-31 is more intense than that of pure AlPO-31 suggesting preferential occupation of the plane corresponding to it as compared to other planes. The O-H stretch in the IR spectra of the metal-substituted molecular sieves is blue-shifted with respect to the parent AlPO-31 molecular sieves possibly due to metal substitution. Theg values obtained from the ESR spectra of MAPO-31 and NAPO-31 also substantiate framework substitution. Ethylation of toluene was carried out between 300 and 450°C over the above catalysts as a model test reaction. The high toluene conversion over metal-substituted molecular sieves proves the isomorphic substitution of metal ions in the AlPO-31 framework.

Keywords

Molecular sieves MAPO-31 NAPO-31 ZAPO-31 ethylation of toluene 

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References

  1. 1.
    Meier W M, Olson D H and Baerlocher 1996Atlas of zeolite structure types (New York: Elsevier)Google Scholar
  2. 2.
    Wilson S T, Lok B M, Messina C A, Cannan J R and Flanigen E M 1982J. Am. Chem. Soc. 104 1146CrossRefGoogle Scholar
  3. 3.
    Pujado P R, Rabo J A, Antos G J and Genbicki S A 1992Catal. Today 13 113CrossRefGoogle Scholar
  4. 4.
    Flanigen E M, Lok B M, Patton R L and Wilson S T 1986 InNew developments in zeolite science and technology-Procs. 7th International Zeolite Conference (eds) J A Murakami, A Ijina and J W Ward (Tokyo: Kodansha) p. 103Google Scholar
  5. 5.
    Finger G, Komatowski J, Jancke K, Matschat R and Baur W H 1999Microporous Mesoporous Mater. 33 127CrossRefGoogle Scholar
  6. 6.
    Kannan C, Elangovan S P, Palanichamy M and Murugesan V 1988Indian J. Chem. Technol. 5 65Google Scholar
  7. 7.
    Kannan C 1999Aluminophosphate-based molecular sieves: Synthesis, characterization and catalytic applications, PhD thesis, Anna University, ChennaiGoogle Scholar
  8. 8.
    Zubowa H L, Alsdorf E, Fricke R, Nelssendorfer F and Mendau J R 1990J. Chem. Soc., Faraday Trans. 86 2307CrossRefGoogle Scholar
  9. 9.
    Bennett J and Kirchner R M 1992Zeolites 12 338CrossRefGoogle Scholar
  10. 10.
    Ashtekar S, Chilukuri V V, Prakash A M, Harendranath C S and Chakrabarty D K 1995J. Phys. Chem. 99 6937CrossRefGoogle Scholar
  11. 11.
    Zecchina A and Otero Arean C 1996Chem. Soc. Rev. 187Google Scholar
  12. 12.
    Lohse U, Bruckner A, Kintscher K and Pariitz B 1998J. Chem. Soc., Faraday Trans. 91 1173CrossRefGoogle Scholar
  13. 13.
    Adeola F and McCusker L B 1991Zeolites 11 460CrossRefGoogle Scholar
  14. 14.
    Elangovan S P, Krishnasamy V and Murugesan V 1995Bull. Chem. Soc. Jpn. 68 3659CrossRefGoogle Scholar
  15. 15.
    Prakash A M, Ashtekar S and Chakrabarty D K 1995J. Chem. Soc., Faraday Trans. 91 1045CrossRefGoogle Scholar
  16. 16.
    Halik Ch, Lercher J A and Mayer H 1988J. Chem. Soc., Faraday Trans. 84 4457CrossRefGoogle Scholar
  17. 17.
    Xu Y, Maddox P J and Thomas J M 1989Polyhedron 8 819CrossRefGoogle Scholar

Copyright information

© Indian Academy of Sciences 2000

Authors and Affiliations

  • V. Umamaheswari
    • 1
  • C. Kannan
    • 1
  • Banumathi Arabindoo
    • 1
  • M. Palanichamy
    • 1
  • V. Murugesan
    • 1
  1. 1.Department of ChemistryAnna UniversityChennaiIndia

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