Chemical Engineering - Chemical Reaction Engineering - Discussion

Final Answer:

Large reactor followed by a smaller one.
Performance of CSTRs in Series:

In a CSTR, the concentration drops abruptly from the inlet to the outlet.
For first-order reactions, the conversion increases with residence time.
When placing two CSTRs in a series:

The first reactor sees the highest reactant concentration, so it contributes more to overall conversion.
Therefore, placing the larger volume reactor first leads to better performance because it exploits the high initial concentration, where the rate is highest.

When n>1, PFR-small CSTR-large CSTR. Prefer late mixing.
When n<1, Big CSTR-small CSTR- PFR.

Prefer early mixing.
N=1 (FIRST order) - any arrangement can be followed.

Option B is right, for +ve order small followed by large.

C is the correct answer. Option B is for, order >1.

Correct answer is B.

Smaller CSTR followed by larger will give higher yield and conversion.

It is independent on concentration.

Option B is the correct answer.