Design of a Fixed Bed Reactor for Catalytic Hydrocarbon Oxidation

C Design or Simulation of a Fixed Bed Reactor for Catalytic Hydrocarbon Oxidation 

In this example the design or simulation of a multitubular reactor for catalytic hydrocarbon oxidation is discussed (Froment [76]). The case considered here is of a rather complex nature, that is. 

This reaction model is fairly representative of the gas phase air oxidation of o-xylene into phthalic anhydride on VjOj catalysts. A represents o-xylene, B phthalic anhydride, and C the final oxidation products CO and COj, lumped together. The process conditions were already described in Sec. 11.5.b. The purpose of this example is mainly to check whether or not serious radial temperature gradients occur in such a reactor. For a better approximation of reality a reaction model is chosen that is closer to the true model than the one used in Sec. ll.S.b. In addition, it illustrates a yield problem, such as is often encountered in industrial practice. 

Due to the very large excess of oxygen the rate equations will be considered to be of the pseudo-first-order type, so that, at atmospheric pressure. 

The constants in these equations have the following meaning  

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