Steady-State CSTR with Higher-Order, Reversible Kinetics

2 Steady-State CSTR with Higher-Order, Reversible Kinetics 

Chapter 9 Continuous Stirred Tank and the Plug Flow Reactors 

0 = Cafqf — Caq — kabCaCbV + kdCd V 0 = Cbfqf - Cbq - kabCaCbV + kdCd V 0 = -Cdq + kabCaCbV - kdCd V 

The result is that we get two sets of symbolic solutions forthe concentrations. The first set 

This last equation shows why the CSTR at steady state is such a valuable tool to the experimentalist seeking kinetic parameters. The rate of reaction, independent of the form of the kinetics, is simply the change in concentration of A between the feed and exit streams divided by the holding time. We will see this repeatedly. 

There is something to learn from rearranging the second equation also  

Given the rate of a chemical reaction, and the target production rate Cd q we can compute the volume necessary for a well-mixed reactor to achieve this output. Thus in a very real sense this becomes a useful design equation to be employed in the earliest stages of a study of economic feasibility. 

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