The liquid-phase reaction in Problems P11-4A and P12-7A is to be carried out in a semibatch reactor. There are 500 mol of A initially in the reactor at 25°C. Species B is fed to the reactor at 50°C and a rate of 10 mol/min. The feed to the reactor is stopped after 500 mol of B has been fed.
1. Plot and analyze the temperature Q_r, Q_g and conversion as a function of time when the reaction is carried out adiabatically. Calculate to t = 2 hours.
2. Plot and analyze the conversion as a function of time when a heat exchanger (UA = 100 cal/min · K) is placed in the reactor and the ambient temperature is constant at 50°C. Calculate to t = 3 hours.
3. Repeat part (b) for the case where the reverse reaction cannot be neglected. New parameter values:

Problems P12-7A

Use the data in Problem P11-4A for the following reaction. The elementary, irreversible, organic liquid-phase reaction
A + B → C is carried out in a flow reactor. An equal molar feed in A and B enters at 27°C, and the volumetric flow rate is 2 dm³/s and C_A0 = 0.1 kmol/m³.
Additional information:
(a) Calculate the conversion when the reaction is carried out adiabatically in one 500-dm³ CSTR and then compare the results with the two adiabatic 250-dm³ CSTRs in series.
The reversible reaction is now carried out in a PFR with a heat exchanger. Plot and then analyze X, X_e, T, T_a, Q_r, Q_g, and the rate, –r_A, for
the following cases:
(b) Constant heat-exchanger temperature T_a
(c) Co-current heat exchanger T_a.
(d) Countercurrent heat exchanger T_a.
(e) Adiabatic operation
(f) Make a table comparing all your results (e.g., X, X_e, T, T_a). Write a paragraph describing what you find.
(g) Plot Q_r and T_a as a function of V necessary to maintain isothermal operation.

Data From Problem P11-4A

The elementary, irreversible, organic liquid-phase reaction A + B → C is carried out adiabatically in a flow reactor. An equal molar feed in A and B enters at 27°C, and the volumetric flow rate is 2 dm³/s and C_A0 = 0.1 kmol/m³.
Additional information:

PFR
a. Plot and then analyze the conversion and temperature as a function of PFR volume up to where X = 0.85. Describe the trends.
b. What is the maximum inlet temperature one could have so that the boiling point of the liquid (550 K) would not be exceeded even for complete conversion?
c. Plot the heat that must be removed along the reactor (Q˙ vs. V) to maintain isothermal operation.
d. Plot and then analyze the conversion and temperature profiles up to a PFR reactor volume of 10 dm³ for the case when the reaction is reversible with K_C = 10  m³/kmol at 450 K. Plot the equilibrium conversion profile. How are the trends different than part (a)?

CSTR
e. What is the CSTR volume necessary to achieve 90% conversion?

BR
f. The reaction is next carried out in a 25 dm³ batch reactor charged with N_A0 = 10 moles. Plot the number of moles of A, N_A, the conversion, and the temperature as a function of time.

Transcribed Image Text:

k = 0.01 (dm/mol - min) at 300 K with E= 10 kcal/mol Vo = 50 dm, up = 1 dm/min, CAO = CB0= 10 mol/dm For the reverse reaction: k, = 0.1 min at 300 K with E,= 16 kcal/mol