DOI QR코드

DOI QR Code

Partially Dehydrated Fully Zn2+-exchanged Zeolite Y (FAU, Si/Al = 1.70) and Its Structure

  • Seo, Sung Man (Department of Applied Chemistry, Andong National University) ;
  • Kim, Young Hun (Department of Environmental Engineering, Andong National University) ;
  • Lee, Seok Hee (Department of Science Education, Busan National University of Education) ;
  • Lim, Woo Taik (Department of Applied Chemistry, Andong National University)
  • Received : 2013.02.28
  • Accepted : 2013.04.10
  • Published : 2013.04.30

Abstract

The crystal structure of partially dehydrated fully $Zn^{2+}$-exchanged zeolite Y was determined by X-ray diffraction techniques in the cubic space group $Fd\bar{3}m$ at 294(1) K and refined to the final error indices $R_1/wR_2$ = 0.035/0.119 for $|Zn_{35.5}(H_2O)_{13}|[Si_{121}Al_{71}O_{384}]$-FAU. About 35.5 $Zn^{2+}$ ions per unit cell are found at six distinct positions; sites I, I', a second I', II', II, and a second II. In sodalite cavities, the 11 water molecules coordinate to Zn(I'b) and/or Zn(II') ions; each of two $H_2O$ bonds to a Zn(IIb) in supercages. Two different $Zn^{2+}$ positions near 6-oxygen ring are due to their Si-Al ordering in tetrahedral site by Si/Al ratio leading to the different kinds of 6-rings.

Keywords

References

  1. Bae, D., S. Zhen, K. Seff. 1999. Structure of dehydrated $Zn^{2+}$-exchanged zeolite X. Overexchange, framework dealumination and reorganization, stoichiometric retention of monomeric tetrahedral aluminate. J. Phys. Chem. B. 103: 5631-5636. https://doi.org/10.1021/jp990854+
  2. Blower, C.J., T.D. Smith. 1993. The gas-phase decomposition of nitromethane over metal ion-exchanged sodium Y zeolite and sodium X zeolite. Zeolites. 13: 394-398. https://doi.org/10.1016/0144-2449(93)90156-W
  3. Brooks, C. 1990. Desulfurization over metal zeolites. Sep. Sci. Technol. 25: 1817-1828. https://doi.org/10.1080/01496399008050426
  4. Breck, D.W. 1974. Zeolite molecular sieves. John Wiley & Sons, New York. p. 93.
  5. Brownscombe, T.F. 1991. Basic alkaline earth metal-zeolite compositions. US Patent 5053372.
  6. Bruker-AXS (ver. 6.12), XPREP. 2001. Program for the automatic space group determination. Bruker AXS Inc., Madison, Wisconsin, USA.
  7. Chu, P. 1978. Aromatization of ethane. US Patent 4120910.
  8. Gairbekov, T.M., M.I. Takaeva, A.K. Manovyan, I.L. Aleksandrova. 1989. Aromatization of gasoline on zinc-modified zeolite-containing catalysts. Chem. Technol. Fuels Oils. 25: 473-475. https://doi.org/10.1007/BF00726000
  9. Kumar, N., L.E. Lindfors, R. Byggningsbacka. 1996. Synthesis and characterization of H-ZSM-22, Zn-H-ZSM-22 and Ga-H-ZSM-22 zeolite catalysts and their catalytic activity in the aromatization of n-butane. Appl. Catal. A. 139: 189-199. https://doi.org/10.1016/0926-860X(95)00327-4
  10. Lee, S.H., Y. Kim. 2000. Two crystal structures of dehydrated $Zn^{2+}$-exchanged zeolite X: $Zn_{46}Si_{100}Al_{92}O_{384}{{\cdot}}8ZnO$ and $Zn_{13}Tl_{66}Si_{100} Al_{92}O_{384}{{\cdot}}2ZnO$. Bull. Korean Chem. Soc. 21: 180-186.
  11. Lim, W.T., S.M. Seo, G.H. Kim, H.S. Lee, K. Seff. 2007. Six single-crystal structures showing the dehydration, deamination, dealumination, and decomposition of $NH_{4}^{+}$-exchanged zeolite Y (FAU) with increasing evacuation temperature. Identification of a Lewis acid site. J. Phys. Chem. C. 111: 18294-18306. https://doi.org/10.1021/jp0742721
  12. Loewenstein, W. 1954. The distribution of aluminum in the tetrahedral of silicates and aluminates. Am. Mineral. 39: 92-96.
  13. Otwinowski, Z., W. Minor. 1997. Processing of X-ray diffraction data collected in oscillation mode. Methods Enzymol. 276: 307-326. https://doi.org/10.1016/S0076-6879(97)76066-X
  14. Peterson, B.K. 1999. A simulated annealing method for determining atomic distributions from NMR data: silicon and aluminum in faujasite. J. Phys. Chem. B. 103: 3145-3150. https://doi.org/10.1021/jp984515c
  15. Rhee, K.H., F.R. Brown, D.H. Finseth, J.M. Stencel. 1983. Infrared studies on the acidity of metal impregnated ZSM-5. Zeolites. 3:344-347. https://doi.org/10.1016/0144-2449(83)90180-X
  16. Seo, S.M., H.S. Kim, M. Park, W.T. Lim. 2011. Synthesis and structural refinement of fully dehydrated fully $Zn^{2+}$-exchanged zeolite Y (FAU), $Zn_{35.5}[Si_{121}Al_{71}O_{384}]$-FAU. J. Porous Mater. 18:47-56. https://doi.org/10.1007/s10934-010-9355-7
  17. Sheldrick, G.M. 1997. SHELXL97, Program for the refinement of crystal structure. University of Gottingen, Germany.
  18. Van Bekkum, H., E.M. Flanigen, P.A. Jacobs, J.C. Jansen. 2001. Introduction to zeolite science and practice. Elsevior. p. 44.
  19. Ziolek, M., K. Nowinska, K. Lecksowska. 1992. Reactions of alcohols with hydrogen sulfide over zeolites: Part V. The role of Bronsted acid sites in thiols formation-A comparative study of zeolites and heteropoly acids. Zeolites. 12: 710-715. https://doi.org/10.1016/0144-2449(92)90120-E