Abstract
A mixture ofn-octane (nC8) and 2, 2, 4-trimethylpentane (224-TMP) was cracked over an alumina-pillared montmorillonite (Al-PILC) acid catalyst as a means of characterising its pore structure and shape selectivity. The shape selectivity of the catalyst was quantified by a time dependent parameter analogous to the constraint index, called the selectivity ratio (SR), and defined as log (fraction of nC8 remaining)/log (fraction of 224-TMP remaining). The SR was measured over Al-PILC, a 0.16 wt% Pt loaded Al-PILC, a Y zeolite, and an amorphous silicaalumina. The SR was greater over Al-PILC compared with Y-zeolite even though the pore openings of the Al-PILC were of similar or larger size than those in the Y-zeolite. Doping AlPILC with Pt caused a large increase in the SR. As found with constraint index measurements, internal pore dimensions and reaction mechanisms appear to be the determinants of SR. However, SR is better capable of discriminating larger pore microporous materials.
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References
R.J. Lussier, J.S. Magee and D.E.W. Vaughan, in:Proc. 7th Can. Symp. on Catalysis, Alberta 1980, p. 88.
M.L. Occelli, Ind. Eng. Chem. Prod. Res. Dev. 22 (1983) 553.
J. Shabtai, F.E. Massoth, M. Tokarz, G.M. Tsai and J. McCauley, in:Proc. 8th Int. Congr. on Catalysis, Vol. 4, Berlin 1984 (Dechema, Frankfurt-am-Main, 1984) p. 735.
K. Suzuki, M. Horio and T. Mori, Mater. Res. Bull. 23 (1988) 1711.
D.E.W. Vaughan and R.J. Lussier, in:Proc. 5th Int. Conf. on Zeolites, Naples 1980, ed. L.V.C. Rees (Heyden, London, 1980) p. 94.
V.J. Frilette, W.O. Haag and R.M. Lago, J. Catal. 67 (1981) 218.
L.A. Bruce, T.W. Turney, P.T.T. Ho and J.F. Mathews, in:Proc. CHEMECA 86, Adelaide, August 1986 (Institution of Engineers, Australia) p. 467.
E. Kikuchi and T. Matsuda, Catal. Today 2 (1988) 297.
C. Doblin, J.F. Mathews and T.W. Turney, Appl. Catal. 70 (1991) 197.
W.A. Dietz, J. Gas Chromatogr. 5 (1967) 68.
J.R. Anderson and K.C. Pratt,Introduction to Characterisation and Testing of Catalysts (Academic Press, Sydney, 1985) ch. 6.
M.L. Occelli and D.H. Finseth, J. Catal. 99 (1986) 316.
M.L. Occelli, J.M. Stencel and S.L. Suib, in:Chemistry of Microporous Crystals, Studies Surf. Sci. Catal., Vol. 60, eds. I. Tomoyuki, N. Seitaro and T. Takashia (Elsevier, Amsterdam, 1991) p. 353.
H. Van Damme and J.J. Fripiat, J. Phys. Chem. 82 (1985) 2785.
F. Tsvetkov and J. White, J. Am. Chem. Soc. 110 (1988) 3183.
S.M. Csiscery, Zeolites 4 (1984) 202.
W.O. Haag, R.M. Lago and P.B. Weisz, Faraday Discussions Chem. Soc. 72 (1981) 317.
D.W. Breck,Zeolite Molecular Sieves (Wiley, New York, 1974).
J. Scherzer, Cat. Rev.-Sci. Eng. 31 (1989) 215.
M. Guisnet, G. Gianetto, P. Hilaireau and G. Perot, J. Chem. Soc. Chem. Commun. (1983) 1411.
D. Santilli, Appl. Catal. 60 (1990) 137.
W.O. Haag and R.M. Dessau, in:Proc. 8th Int. Congr. on Catalysis, Vol. 2, Berlin 1984 (Dechema, Frankfurt-am-Main, 1984) p. 305.
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Doblin, C., Mathews, J.F. & Turney, T.W. Shape selective cracking ofn-octane and 2,2,4-trimethylpentane over an alumina-pillared clay. Catal Lett 23, 151–160 (1994). https://doi.org/10.1007/BF00812143
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DOI: https://doi.org/10.1007/BF00812143