Dealumination of HZSM-5 zeolites. II. Methanol to gasoline conversion

Journal Article · Sat Jun 01 00:00:00 EDT 1996 · Journal of Catalysis

DOI:https://doi.org/10.1006/jcat.1996.0192· OSTI ID:471630

Campbell, S M ^[1]; Coddington, J M ^[1]; Bibby, D M ^[2]

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1. Univ. of Auckland (New Zealand)
2. Industrial Research Ltd., Petone (New Zealand); and others

Changes in the structure and properties of HZSM-5 zeolites used for extended periods as catalysts in the conversion of methanol to gasoline have been investigated. HZSM-5 samples were characterized using solid-state NMR spectroscopy ({sup 27}Al and {sup 29}Si MAS), infrared spectroscopy; chemical analysis, water and nitrogen adsorption, X-ray diffraction, X-ray photoelectron spectroscopy, and {sup 129}Xe NMR spectroscopy of adsorbed xenon. Use of HZSM-5 in methanol conversion was found to cause dealumination of the zeolite lattice. The catalyst lifetime, however, increased after repeated use in MTG cycles. The dealumination is caused by water produced during methanol conversion, although the extralattice aluminum species formed appeared to differ from those produced by calcination or mild hydrothermal treatment. The increase in catalyst lifetime is attributed to a decreased rate of coke formation in catalysts containing lower densities of acid sites. 17 refs., 9 figs., 1 tab.

• OSTI ID: 471630
• Journal Information: Journal of Catalysis, Vol. 161, Issue 1; Other Information: PBD: Jun 1996
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
36 MATERIALS SCIENCE
ZEOLITES
CATALYTIC EFFECTS
METHANOL
ALKYLATION
GASOLINE
CHEMICAL PREPARATION
NUCLEAR MAGNETIC RESONANCE
ABSORPTION SPECTROSCOPY
SORPTIVE PROPERTIES
ADSORPTION
NITROGEN
WATER
X-RAY DIFFRACTION
X-RAY SPECTROSCOPY
SCANNING ELECTRON MICROSCOPY
CATALYSTS
HETEROGENEOUS CATALYSIS