Month: February 2019

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 ____________?

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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

Pure ethanol vapor is fed to a reactor packed with alumina catalyst, at the rate of 100 kmole / hr. The reactor products comprise: ethylene: 95 kmole / hr, water vapour: 97.5 k mole / hr and diethyl ether: 2.5 kmole/hr. The reactions occuring can be represented by: C2H5OH → C2H4 + H2O 2C2H5OH → C2H5 – O – C2H5 + H2O The percent conversion of ethanol in the reactor is________________?

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Pure ethanol vapor is fed to a reactor packed with alumina catalyst, at the rate of 100 kmole / hr. The reactor products comprise: ethylene: 95 kmole / hr, water vapour: 97.5 k mole / hr and diethyl ether: 2.5 kmole/hr. The reactions occuring can be represented by: C2H5OH → C2H4 + H2O 2C2H5OH → C2H5 – O – C2H5 + H2O The percent conversion of ethanol in the reactor is________________?

A. 100
B. 97.5
C. 95
D. 2.5

‘If the catalyst pore size is small in comparison with the mean free path, collisions with the pore wall controls the process’. The diffusivity under this condition is called ‘Knudsen diffusivity’, which is affected by the_____________________?

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‘If the catalyst pore size is small in comparison with the mean free path, collisions with the pore wall controls the process’. The diffusivity under this condition is called ‘Knudsen diffusivity’, which is affected by the_____________________?

A. Pressure
B. Temperature
C. Both A. & B.
D. Neither A. nor B.

In a semi-batch reactor __________________?

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In a semi-batch reactor __________________?

A. Mixing takes place in axial direction only
B. Velocity of reaction can be controlled
C. Condition similar to plug flow reactor exists
D. Residence time is constant

A catalyst loses its activity due to__________________?

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A catalyst loses its activity due to__________________?

A. Loss in surface area of the active component
B. Agglomeration of metal particles caused by thermal sintering of the solid surface
C. Covering of the catalytic active sites by a foreign substance
D. All A., B. and C.

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) ?

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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