ISSN:
1572-879X
Keywords:
ethylene
;
aromatics
;
Ga/ZSM-5
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Ga/ZSM-5 is an effective catalyst for the conversion of dilute (3%) ethylene-in-methane reactant streams into aromatic hydrocarbons at 500–550°C. A Ga loading as low as 0.5 wt% is sufficient to obtain maximum yields of aromatic products. At 520°C, an ethylene conversion of 93%, with an aromatics selectivity of 81%, was obtained over a 5 wt% Ga/ZSM-5 catalyst. The conversion of ethylene into aromatics over Ga/ZSM-5 catalysts involves a complex sequence of oligomerization, isomerization, cracking, and cyclization reactions that occur on Brønsted acid zeolites in the zeolite. The role of the gallium, which exists as both Ga3+ at zeolitic exchange sites and as Ga2O3 within the channels and on the external surface of the calcined catalyst, is to promote dehydrogenation of the acid-catalyzed oligomerization and cyclization products.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1019046714762
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