Batch process is preferred over continuous process, when the___________________?

Related Mcqs:

1. Sometimes, batch process is preferred over continuous process, when the product___________________?

   A. Quality & yield cannot be achieved in continuous processes, because of long residence time
   B. Sales demand is fluctuating
   C. Both A. & B.
   D. Neither A. nor B.

2. The first order series reaction as shown in the bellow figure is conducted in a batch reactor. The initial concentrations of A, B and C (CA0, CB0, CC0 respectively) are all non-zero. The variation of CB with reaction time will not show a maximum, if___________________?

   A. k2 CB0 > k1 CA0
   B. k CA0 > k2.CB0
   C. CB0 > CA0
   D. CA0 > CB0

3. A second order liquid phase reaction, A → B, is carried out in a mixed flow reactor operated in semi batch mode (no exit stream). The reactant A at concentration CAF is fed to the reactor at a volumetric flow rate of F. The volume of the reacting mixture is V and the density of the liquid mixture is constant. The mass balance for A is_______________________?

   A. d(VCA)/dt = -F (CAF – CA) – kCA2V
   B. d(VCA)/dt = F (CAF – CA) – kCA2V
   C. d(VCA)/dt = -FCA – kCA2V
   D. d(VCA)/dt = FCAF – kCA2V

4. Which of the following fixes the volume of a batch reactor for a particular conversion and production rate ?

   A. Operating conditions (e.g. pressure and temperature)
   B. Rate constant
   C. Density of mixture
   D. None of these

5. The first order gas phase reaction as shown in the bellow figure is conducted isothermally in batch mode. The rate of change of conversion with time is given by________________?

   A. dXA/dt = k1 (1 – XA)2 (1 + 2XA)
   B. dXA/dt = k1 (1 – XA) (1 + 0.5XA)
   C. dXA/dt = k1 (1 – XA)
   D. dXA/dt = k1 (1 – XA)/(1 + XA)

6. A batch reactor suffers from following disadvantage ?

   A. Poor product quality control
   B. High labour and handling cost
   C. High shutdown time requirement for emptying, cleaning and refilling
   D. All A., B. and C.

7. The conversion for a second order, irreversible reaction (constant volume) as shown in the bellow figure, in batch mode is given by______________?

   A. 1/(1 + k2 . CA0 . t)
   B. (k2 . CA0 . t)/ (1 + k2 . CA0 . t)
   C. (k2 . CA0 . t)2/ (1 + k2 . CA0 . t)
   D. (k2 . CA0 . t)/ (1 + k2 . CA0 . t)2

8. In a semi-batch reactor _____________________?

   A. Velocity of reaction can be controlled
   B. Maximum conversion can be controlled
   C. Both the reactants flow counter-currently
   D. Residence time is constant

9. Second order consecutive irreversible reaction as shown in the bellow figure, were carried out in a constant volume isothermal batch reactor with different initial feed compositions. Reactor temperature was same in all the cases. In experiments where the ratio of concentration of B to that of A in the initial feed was less than 0.5, the concentration of B increased first, reached a maximum and then declined with time. However, for all experiments where this concentration ratio was 0.5 or above, concentration of B decreased monotonically with time right from the beginning. What is the ratio of the two rate constants (k1/k2) ?

   A. 1/4
   B. 1/2
   C. 2
   D. 4

10. A batch adiabatic reactor at an initial temperature of 373°K is being used for the reaction, A → B. Assume the heat of reaction is – 1kJ/mole at 373°K and heat capacity of both A and B to be constant and equal to 50J/mole.K. The temperature rise after a conversion of 0.5 will be ____________?

    A. 5°C
    B. 10°C
    C. 20°C
    D. 100°C