CHNG3803/9303
Homework
Page numbers refer to Chemical Reaction Engineering by Octave Levenspiel 3rd edition.
1. Problem 1.1 (page 8) reaction rate calculation
2. Problem 1.2 (page 8) reaction rate calculation
3. Problem 2.22 (page 37) reaction mechanism
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4. Problem 2.23 (page 37) mechanism for enzyme catalyzed reactions
5. Example 2.3 (page 29) (change the two temperatures and time to 50 oC for 1 h and 80
o
C for 10 s, 0 oC ≈ 273 K) activation energy
6. Lecture notes page 56, for a second order reaction A + 2B →products -rA=kCACB.
Please show the integrated form is:
When a stoichiometric reactant ration is used, the integrated form is:
7. Problem 3.2 and 3.3 together (page 77) first and second order kinetics
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8. Problem 3.8 (page 77) half-life method
9. Problem 3.13 (page 78) reaction in parallel
10. Problem 3.14 (page 78) reactions in series
11. Problem 3.25 (page 81) (note: you may guest that this is a first-order reversible
reaction) reversible reaction
12. Problem 3.15 and 3.16 (page 79) (note: for the differential method, considering ignore
the 4 data at very low CA concentrations) integral and differential methods for a
reaction with shifting orders.
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13. Problem 3.30 (page 82) varying volume integral method
14. Problem 4.1-4.4 (page 89) stoichiometry
15. Problem 4.5-4.6 (page 89) stoichiometry
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16. An isomerization reaction is carried out in a batch reactor. The reaction is first order
with a reaction rate coefficient is 0.8 h-1. The isomer liquid (A) has a density of 900
kg m-3 at 160 °C. The isomer is filled into the reactor in 10 min at room temperature.
14 min is required to heat up the reactor from room temperature to 160 °C. After the
reaction, it requires 15 min to cool down to room temperature, the resulting polymer
liquid at the same density of 900 kg m-3 is emptied in 12 min. We assume the reaction
is negligible during heating or cooling periods. 900 T of polymer solution must be
synthesized in 7000 h of operation per year. The expected reaction conversion is 97%.
What is the required volume of the stirred batch reactor operated isothermally at
160 °C? batch reactor
17. The reaction A+BC+D is carried out at 80 °C in an isothermal, perfectly stirred
tank batch reactor. The reaction rate can be described as second-order, where k=0.058
m3 kmol-1 min-1. At 80 °C, 240 kg of material A (MA=60 g mol-1) and 400 kg of
material B (MB=80 g mol-1) is added into the stirred tank. At this point, the volume of
the (liquid) reaction mixture is 0.9 m3. The reaction does not change the volume. How
much time is required to reach 95% conversion? batch reactor
18. Problem 5.3 (page 113) CSTR
19. Problem 5.4 (page 113) CSTR
20. Problem 5.8 (page 114) CSTR
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21. Problem 5.16 (page 115) CSTR
22. Problem 5.5 (page 113) PFR
23. Problem 5.6 (page 113) PFR
24. Problem 5.14 (page 115) PFR
25. Problem 5.21-5.23 (page 116, 117) Batch, PFR and CSTR
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26. Problem 5.1 (page 113) (assuming the volume would expand linearly with XA, and
reaction proceeds uniformly in the reactor) space and mean residence time
27. Problem 6.13 (page 149) (assuming radioactive material decay as the first order
reaction) two CSTR in series
28. Problem 6.3 (page 147) CSTR +PFR
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29. Problem 6.7 (page 148) CSTR in different sizes
30. Problem 6.15 (page 149) CSTR in different sizes
31. Problem 6.9 (page 148) Recycle reactor
32. Problem 6.21 (page 151) Recycle reactor
33. Problem 6.11 (page 149) Autocatalytic reaction
34. Problem 6.19 (page 150) Autocatalytic reaction
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35. Problem 7.2 to 7.5 (page 165) Contacting pattern for parallel reactions
36. Problem 7.8 to 7.11 (page 165-161) product distribution and reactor size
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37. Problem 7.28 (page 169) product distribution and reactor size
(the example on lecture note page 217)
38. Problem 8.1 (page 201) Contacting patterns for competitive-consecutive reactions
39. Problem 8.2 (page 201) Irreversible first-order reaction in series
40. Problem 8.6 (page 202) Irreversible first-order reaction in series
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41. Problem 8.19 (page 206) Zero-order followed by first-order reaction
42. Problem 8.7 (page 202) Irreversible series-parallel reactions
43. Denbigh reactions
Consider the first order decompositions with rate constant as shown below (k has the
unit of h-1):
CA0=100 mol/L, other reactants have the concentration of 0 before enter the reactor, if
a colleague reports that Cs = 0.02 CA0 in the exit stream of a plug flow reactor, what
can you say about the concentration of the other reactants, A, R, T, and U in the exist
stream?
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44. Problem 8.21 (page 206) Extension of Denbigh reactions
45. Problem 9.5-9.8 (page 238) Design of non-isothermal reactors
46. Problem 9.11 (page 239) Optimum T for multiple reactions
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47. Problem 10.1 (page 246) Reactor selection
48. Problem 10.6 (page 248) Reactor design for parallel reactions
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49. Problem 10.12 (page 251) Reactor design for homogenous catalytic reaction
50. Problem 10.15 (page 252) Optimum temperature of reactor
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