The thermal instability of solid catalysts and the temperature dependence of heterogeneous catalytic process rates

✍ Scribed by K. Østergaard

• Publisher: Elsevier Science
• Year: 1963
• Tongue: English
• Weight: 453 KB
• Volume: 18
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(93)80002-8

✦ Synopsis

The influence of simultaneous heat and mass transfer upon the rate of a heterogeneous catalytic process has been analysed with particular regard to the effect upon the temperature dependence of the Drocess rate. The results are shown in dimensionless Arrhenius diagrams. These diagrams differ very n&kedly from diagrams for isothermal catalyst particles.

The catalyst may exist in several steady states, the apparent activation energy may assume iniinite values, and small changes in temperature may result in very sign&ant changes in the process rate and in the apparent activation energy. It is suggested that "hot spots" in catalytic reactors can be caused by such effects.

The effects are more uronounced for a zero-order reaction in flat catalyst plates than for a lirstorder reaction in spherical catalyst particles.