1. Isothermal reactor design
Lec. 5 week 7

2. Example (1)
Calculate the time necessary to achieve a given conversion X for the irreversible second-order reaction taken place in a Batch reactor
Solution:
Step (1) Mole Balance
The mole baIance on a constant-volume, V = Vo, batch reactor is

3. Second step is to write the rate law:
Third step is the Stoichiometry:
Then combine all the three steps together in one equation

5. Pop up question
Drive the Design Equations for CSTR in termas of concentration: For liquid systems:
General Reactor Design Equation
Assume Steady State
Well Mixed

6. For liquid systems, CA0 is usually given in terms of molarity (mol/dm3)

7. For gas system: For gas systems, CA0 can be calculated using gas laws.

8. Space time for CSTR
It means the holding time or mean residence time in the reactor or in another words; the time necessary to process one reactor volume of fluid based on entrance Conditions

9. Example (2)
Calculate the space time necessary to achieve a given conversion X for the irreversible first-order reaction taken place in a CSTR
Solution
Step (1) Mole Balance

10. Second step is to write the rate law:
Third step is the Stoichiometry:
Combine and rearrange:

11. Example 3: Consider the elementary liquid-phase reaction A B taking place in an ideal batch reactor at constant temperature. Determine the time taken for the concentration of A to become half of its initial concentration.