Coking kinetics of fresh and thermally aged commercial Cr2O3/Al2O3 catalyst

✍ Scribed by J.A. Pen˜a; A. Monzo´n; J. Santamari´a; J.L.G. Fierro

• Book ID: 103963285
• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 844 KB
• Volume: 101
• Category: Article
• ISSN: 0926-860X
• DOI: 10.1016/0926-860x(93)80268-u

✦ Synopsis

The coking behaviour of fresh and of thermally aged Cr,O:,/Al,O:, catalysts has been studied during the dehydrogenation of n-butene to butadiene using a thermogravimetric system. The results show that catalyst aging decreases considerably the rate of the main reaction, but also the rate of coking. As a consequence, the dehydrogenation rates obtained after a certain reaction time with aged catalyst were higher than those for fresh catalyst. The analysis of the coking kinetics on fresh and on thermally aged catalyst and the X-ray photoelectron spectroscopy results obtained on both samples suggest that the deactivation mechanism is not changed by the aging process, and that the main effect of aging is to reduce the number of sites available on the surface for the main and coking reactions.