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Unformatted text preview: a CSTR?
(Same procedure: rate laws into design equation, substitute CB0 and CC0 by expressions
in terms of CA0) CA = C A0 CB = C A0 k1τ CC = C A0 k1k2τ 2 So, what does this look like?
How is it different from a PFR?
•• For series reactions, there is always an optimum residence time
For series reactions, there is always an optimum residence time
to achieve aamaximum yield towards the intermediate product
to achieve maximum yield towards the intermediate product
•• For positive order kinetics, the optimum yield in the PFR is
For positive order kinetics, the optimum yield in the PFR is
always greater than that in aaCSTR
always greater than that in CSTR
How can we rationalize this? How about the BR? L1116
L11 PFR v s CST R: Series Re action
P FR v s CST R: Series Re action Maximum in CB
> optimum in
optimum
residence time!
residence time
How can I calculate
the optimum?
Look for dCB/dτ = 0!
Do it for the PFR! 1 1 0.8
0.8 co c. [ .u.]
connc....
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This note was uploaded on 10/31/2013 for the course CHE E440 taught by Professor Baier during the Fall '13 term at Columbia.
 Fall '13
 Baier
 Reaction

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