Maximum Pressure Difference in a Porous Pellet

Viewed in retrospect, a lot of work can be saved in Example 9.14 by using criterion 7-56. 

For a reactor feed composition of 10 mole % A, 30 mole % P and 60 mole % D and for one molecule of A converted into three molecules of P, for every place inside the reactor 

What is the maximum pressure difference inside a catalyst for the reactor feed given in Example 9.18 The reactor pressure is 20 bar. 

Since vP=3 and kAj = 0.1 we calculate oan = 0.073. From the definition of a it then follows that 

Hence the maximum obtainable pressure inside the catalyst pellet is 21.5 bar, irrespective the size and shape of the catalyst pellet and the reaction kinetics. 

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