Additional Homework Problems

CDP10-VB

  The elementary irreversible gas phase catalytic reaction
     
   

image 10eq33.gif

     
   

is to be carried out in a moving-bed reactor at constant temperature. The reactor contains 5 kg of catalyst. The feed is stoichiometric in A and B. The entering concentration of A is 0.2 mol/dm 3 . The catalyst decay law is zero-order with k D = 0.2 s +1 .

(a) At what catalyst loading rate (kg/s) will the catalyst activity be exactly zero at the exit of the reactor?
(b) Sketch the catalyst activity as a function of catalyst weight (i.e., distance) down the length of the reactor (from 0 to 5 kg) for a catalyst feed rate of 0.5 kg/s. What does an activity of zero mean? Can catalyst activity be less than zero?
(c) What conversion will be achieved for a catalyst feed rate of 0.5 kg/s?
(d) What catalyst loading rate is necessary to achieve 40% conversion?
(e) What is the maximum conversion that could be achieved (i.e., at infinite catalyst loading rate)?

    image 10eq35.gif