EFFECT OF SURFACE DIFFUSION ON THE SELECTIVITY OF CATALYTIC REACTIONS.

Harold H Kung, Mayfair C. Kung

Research output: Contribution to journalArticle

Abstract

The analysis presented indicates that surface diffusion can greatly affect the observed selectivity of a reaction. The presence of surface diffusion reduces the dependence of selectivity on the flow rate. In fact, if surface diffusion of B is much faster than its desorption, a selectivity of unity, independent of flow rate, can be obtained. Conditions used in ultra high vacuum studies (like molecular beam experiments) are equivalent to the extreme of very high flow rate. This analysis shows that depending on the degree of surface diffusion, results from such studies may or may not differ significantly from the conventional studies. Another interesting result due to surface diffusion is the dependence of selectivity on the crystallite size. No such dependence would be expected without surface diffusion. Surface diffusion also results in the increase in selectivity with decreasing loading. The selectivity approaches unity at very low loading but would approach zero in the absence of surface diffusion.

Original languageEnglish
Pages (from-to)891-902
Number of pages12
JournalPreprints Symposia
Volume22
Issue number3
Publication statusPublished - Aug 1977

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Surface diffusion
Flow rate
Molecular beams
Ultrahigh vacuum
Crystallite size
Desorption

ASJC Scopus subject areas

  • Fuel Technology

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EFFECT OF SURFACE DIFFUSION ON THE SELECTIVITY OF CATALYTIC REACTIONS. / Kung, Harold H; Kung, Mayfair C.

In: Preprints Symposia, Vol. 22, No. 3, 08.1977, p. 891-902.

Research output: Contribution to journalArticle

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