CSTR and PFR in series solution..?

Question

I am trying to solve a CRE problem. a)CSTR followed by PFR in series. The volumes of both are given, the entering flow rate is given. The conversion of each reactor seperately is equal to .4. We are also give a table with conversion factors and corresponding reaction rates. The question is what conversion can be acheived with these two in a series. Also, what conversion can be achieved if pfr is followed by cstr?

Answer 1

This problem relies extensively on the analysis of the graph you get plotting FA0/(-rA) vs. (XA).

The information about the conversion of each reactor doesn't help, since you already have the volumes of each.

First of all, plot the graph. Then, fit some "areas" beneath the curve according to each reactor type. More details at http://www.engin.umich.edu/~cre/course/lectures/eight/index.htm#sec5 .
[just skip the discussion about adiabatic reactors---focus solely on the graphs of FA0/-(rA) vs. (XA)].

In a general basis, CSTR's yield rectangles, while PFR's are tightly fit to the curve. These areas are numerically equal to the volumes of each reactor. Your job is to adjust rectangles and shapes under the curve until their areas match the total volume of the reactors.

Answer 2

Cstr And Pfr In Series