Details

This is a model of the partial oxidation of o-xylene in a large excess of oxygen in a 1.5 m long plug flow reactor.

The first-order rate expression:

,

where is rate of reaction (), is the pre-exponential factor in the rate constant (1/s), is activation energy (kJ/mol), is the ideal gas constant (kJ/[mol K]), is absolute temperature in the reactor (K), is pressure (atm), is the ideal gas constant (), is the molar flow rate of the reactant o-xylene (kmol/s), and is the total molar flow rate of the feed (kmol/s).

Mole balance as a function of reactor length:

,

where is distance down the PFR (m), is the cross section area of the PFR (), and is the PFR radius (m).

Energy balance as a function of length:

,

,

,

where and are simplification terms, is the temperature of heat transfer fluid surrounding the reactor (K), is heat of reaction (kJ/kmol), is mass flow rate (kg/s), is the mass heat capacity of gas in reactor (kJ/[kg K]) and is the overall heat transfer coefficient ().

At the PFR inlet () and , where is the feed temperature (K) and is the mole fraction of reactant in the feed.

The screencast video at [2] explains how to use this Demonstration.

References

[1] J. B. Rawlings and J. G. Ekerdt, Chemical Reactor Analysis and Design Fundamentals, Madison, WI: Nob Hill Publishing, 2002 pp. 323–326.

[2] Parametric Sensitivity of Plug Flow Reactor With Heat Exchange. www.colorado.edu/learncheme/kinetics/SensitivityOfPFRHeatExchange.html.