Additional Homework Problems

P12-28_B

The formation of styrene from vinylacetylene is essentially irreversible and follows an elementary rate law:

2 vinylacetylene styrene
2A B

1. Determine the conversion achieved in a 10 dm³ PFR for an entering temperature of 675 K. Plot the temperature and conversion down the length (volume) of the reactor.
   
   
2. Vary the entering temperature and plot the conversion as a function of entering temperature
   
   
3. Vary the ambient temperature in the heat exchanger and find the maximum ambient temperature at which runaway will not occur in the reactor.
   
   
4. Compare your answers with the case when the reaction is carried out adiabatically.
   
   
5. Repeat part B assuming that the reaction is reversible, K_C = 100,000 at 675 K. In addition, a stream of inerts (C_P1 = 100 J/(mol °C)), with F_I = 3 F_A0, enters the reactor. Plot the conversion as a function of the entering temperature. Is there a maximum? If so, why? If not, why not?
   
   
6. Ask another question or suggest another calculation that can be made for this problem.

Additional Information

C_A0 = 1 mol/dm³

Ua = 5 kJ/(s dm³)/K

F_Ao = 5 mol/s

T_a = 700 K

H_RX = -231 - 0.012(T - 298) kJ/mol

C_PA = 0.12222 kJ/(mol K)

k = 1.48 * 10¹¹ exp(-19124/T) dm³/(mol s) T₀ = 675 K

[3rd Ed. P8-9]