Complex Reactions of Ammonia Oxidation

In the two preceding examples, there w as no volume change with reaction conjiequently, we could use concentration as our dependent variable. We now consider a gas-phase reaction with volume change taking place in a PFR. Under these conditions, we must u,se the molar flow rates as our dependent variables. 

Example 6 i0 Calculating Concenirations as Functions of Position for jVWj Oxidation in a PFR 

The following gas-phase reactions take place simultaneously on a metal oxide- ported catalyst  

Writing these equations in terms of symbols yields 

We have convened the specific reaction rates to a per unit volume basis multiplying the k on a per mass of catalyst basis by the bulk density of packed bed (i.e.. Jt = A pB)- 

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