✦ LIBER ✦

Effectiveness factor for surface diffusion and reaction on catalyst surface

✍ Scribed by H.Y. Sohn; R.P. Merrill; E.E. Petersen

Publisher: Elsevier Science
Year: 1970
Tongue: English
Weight: 618 KB
Volume: 25
Category: Article
ISSN: 0009-2509
DOI: 10.1016/0009-2509(70)80038-0

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✦ Synopsis

mathematical model to calculate the effectiveness factor for surface reactions coupled with surface diffusion on a solid-catalyst surface with discrete adsorption centers and the solutions for integral-order reactions are presented. The combined effect of intrinsic reaction and surface diffusion results in apparent orders of (n + 1)/2 and apparent activation energies which are the arithmetic average of those for surface diffusion and chemical reaction. A useful approximate solution has been obtained to give a closed-form solution to the second-order reaction case for the proposed model. Order-of-magnitude calculations indicate that surface diffusion may affect the behavior of useful polyfunction~l catalysts.

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