Exercise 1 solution

1. Exercise 1 solution Lecturer: Miss Anis Atikah Ahmad Tel: +604 976 8190 Email: anisatikah@unimap.edu.my

2. Questions The reaction below is carried out isothermally in a continuous-flow reactor. A  B (a) Calculate both the CSTR and PFR reactor volume necessary to consume 99% of A (i.e., CA = 0.01 CA0) when the entering molar flow rate is 5 mol/h, assuming the reaction rate –rA is : (i) Zero order with reaction rate expression of –rA= k (k = 0.05 mol/h.dm3) (ii) First order with reaction rate expression of –rA=kCA (k = 0.0001 s-1) (iii) Second order with reaction rate expression of –rA= kCA2(k = 3 dm3 /mol. h) The entering volumetric flow rate is 10 dm3/h. (Note: FA = CAυ. For a constant volumetric flow rate υ=υ0, then FA = CAυ0. Also, CA0 =FA0/υ0 = [5 mol/h]/[10 dm3/hr]=0.5 mol/dm3. ) (b) Calculate the time necessary to consume 99 % of species A in a 1000 dm3 constant volume batch reactor with CA0 = 0.5 mol/dm3 and rA in part a)(i),(ii), (iii).

3. Substitute with the rate given (i)

4. (i) Volume of PFR is same as volume for a CSTR since the rate is constant & independent of concentration.

5. (ii)

6. (ii) Substituting the values;

7. (iii)

8. (iii)

9. (i) NA = CAV, CA = NA/V A Zero order:

10. (ii) (iii)

11. THANK YOU