Question

The reaction 2A + B → C obeys the rate law –rB = kCB2, where k = 0.25 L/mol.s at 75˚C. A is available as a 1.5 M solution and B as a 1 M solution.

a) A 26 L/s stream of solution A and 30 L/s stream of solution B are combined just before being introduced into a CSTR. If a 150 L reactor is available, how many mole/h of C could be produced?

b) You receive some financing to increase C production. After some investigation, you find you could either add a second 150 L CSTR in series with the first or add another heater to increse the reactor temperature to 85 ˚C. Which is the best option? (The reaction has an activation energy of 70 kJ/mol.)

Answer 1

GIVEN

A.

for cstr  

substituting on above equation we get

  

above equation A

we put values in above equation we will get a quadratic equation for X

solving the values for X

we get X1.8,.55

we take X as .55

Now

So of C is produced.

B.

To increase production of c

if temperature is increased

from arrhenius equation we find new k value

substituting values of

using the same steps in b part to find X we replace the value of k with .246

Solving equation A

We get a quadratic equation

Solving above eqn we get

Another condition is adding a cstr of equal volume in series

-

Substituting the values we get equation

So this has better conversion cstr in series is used.