Chapter 2: Conversion and Reactor Sizing

Frequently Asked Questions (FAQs)

1. Why would you choose to have CSTRs and PFRs in series?

   It is what reactors you might have on hand that you could connect together to obtain a high conversion.

2. How would the problem involving three reactors in series in Chapter 2 change if there were sidestreams between?

   One can't use the definition of total conversion up to a point because the reactant is fed to the stream between reactors under these circumstances. One must work in terms of molar flow rates when writing the mole balances.

3. Is there ever a time when a CSTR will have a lower volume than a PFR for the same conversion and flow rates?

   Yes, for some adiabatic, exothermic reactions.

4. In the 3-reactor series, (CSTR, PFR, CSTR) why wouldn't you just use the PFR to have the least volume overall to achieve the best conversion?

   You would if you had a PFR large enough. We are assuming that you have these reactors available for your use. See the ICM-Staging.

5. For the three reactors in series example, can a PFR use liquid like the 2 CSTRs?

   Yes.