Chapter 10: Catalysis and Catalytic Reactors
Additional Homework Problems
CDP10-UB
| The cracking of normal paraffins (Pn) can be modeled as | ||
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with surface reaction as the rate-limiting step. The rate of reaction
has been found to increase with increasing temperature up to a carbon number of 15
(i.e., ) [J. Wei, Chem. Eng. Sci., 51,
2995 (1996)]. The rate was found to decrease with increasing temperature for a carbon
number greater than 16. The reactions are carried out at sufficiently high temperatures
that
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Plot the heat of adsorption (i.e., )
and the apparent activation energy E * as a function of carbon number. Suggest
an explanation for the unusual temperature dependence discussed above.
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| The value E n appears to be independent of carbon number. |
[J. Wei, Chem. Eng. Sci., 51, 2995 (1996)]