Chapter 2 Self Test

Numerical Evaulation of an Integral

Consider the liquid phase reaction


which is to take place in a PFR. The following data was obtained in a batch reactor.

                           

X

0

0.4

0.8

-ra(mol/dm3.s) 0.01 0.008

0.002



If the molar feed of A to the PFR is 2 mol/s, what PFR volume is necessary to achieve 80% conversion under identical conditions as those under which the batch data was obtained?


Hint 1: What is the PFR design equation and how should the data be plotted?

Hint 2: How can you evaluate the design equation?

Full Solution

 

 

 

 

 

 

 

 

 

 

 

 

 

Hint 1

FAo = 2 mol/s, fed to a plug flow reactor

Thus, one needs (1/-rA) as a function of X


Back to Problem

 

 

 

 

 

 

 

 

 

 

 

 

 

Hint 2


You can either take the area under the curve and multiply by FAO or you can use one of the formulas in Appendix A.4.  

Back to Problem

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Solution


FAo = 2 mol/s, fed to a plug flow reactor

Thus, one needs (1/-rA) as a function of X


You can either take the area under the curve and multiply by FAO or you can use one of the formulas in Appendix A.4.  

For Simpon's three point formula we have:


To reach 80% conversion, your PFR must be 293.3 dm3.

 

Back to Chapter 2