Temperature programmed oxidation of coked H-gallosilicate (MFI) propane aromatization catalyst: Influence of catalyst composition and pretreatment parameters

Journal Article · Sat Mar 01 04:00:00 EST 1997 · Journal of Catalysis

DOI:https://doi.org/10.1006/jcat.1997.1500· OSTI ID:478763

Choudhary, V R; Devadas, P; Sansare, S D ^[1]; Guisnet, M ^[2]

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1. National Chemical Lab., Pune (India)
2. Universite de Poitiers (France)

Temperature programmed oxidation (TPO) of H-gallosilicate (MFI) coked in the propane aromatization at 550{degrees}C for a time-on-stream of 7-8 h has been investigated by measuring point to point the consumption of oxygen and also the formation of the both CO and CO{sub 2} (by GC analysis using a 16-loop gas sampling valve) during the TPO run from 50{degrees} to 900{degrees}C at a linear heating rate of 20{degrees}C min{sup -1} in a flow (50 cm{sup 3} min{sup -1}) of a O{sub 2}-He mixture (8.0 mol% O{sub 2}). The SiGa and Na/Ga ratios, calcination temperature, and hydrothermal pretreatments of the zeolite and also the presence of binder (silica or kaolin) in the catalyst have a strong influence on the TPO of coked zeolite. The influence is attributed to changes in the zeolite properties (viz., zeolitic acidity or framework Ga and non-GW Ga-oxide species), which affect the coke oxidation both directly and/or indirectly, by controlling the nature of coke formed during the coking process. 23 refs., 4 figs., 2 tabs.

• OSTI ID: 478763
• Journal Information: Journal of Catalysis, Journal Name: Journal of Catalysis Journal Issue: 2 Vol. 166; ISSN JCTLA5; ISSN 0021-9517
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
10 SYNTHETIC FUELS
40 CHEMISTRY
AROMATIZATION
CATALYSTS
CATALYTIC EFFECTS
COKE
GALLIUM COMPOUNDS
OXIDATION
SILICATES
ZEOLITES