Print: | ISSN 0256-1115 |
Online: | ISSN 1975-7220 |
Korean Journal of Chemical Engineering,
Vol.9, No.2, 60-65, 1992 STRUCTURE AND ACIDITY MODIFICATION OF MORDENITE THROUGH ISOMORPHOUS Fe SUBSTITUTION
A series of Fe-modified mordenite were hydrothermally synthesized. The effects of substrate composition, aging time, reaction temperature, and reaction time upon the crystallization of the mordenite were investigated. Isomorphous substitution of Fe was confirmed by FT-IR and EPR analysis. Acid strength and acid sites distribution of each catalyst were measured by pyridine TPD, which showed that the number of strong acid sites in H-Fe-mordenite are smaller than in H-Al-mordenite. Structural characteristics and thermal stability were also examined using XRD, SEM and TG. Fe-substitution into the mordenite structure have resulted in substantial decrease in thermal stability. H-Fe-mordenite catalysts showed high selectivity towards p-xylene in toluene alkylation and in xylene isomerization reaction, compared with those obtained using H-Al-mordenite showed little hexane cracking activity. Deactivation in both toluene alkylation and xylene isomerization reaction and coke formation over H-Fe-mordenite in these reactions were negligible.
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