Page 560 - Elements of Chemical Reaction Engineering Ebook

530 Steady-State Nonisothermal Reactor Design Chap. 8

Discuss how should the reaction be carried (Le. uo =, To =, etc.) out to produce
100 mol B/day?[No ans. given in solutions manual to this revised problem]
P8-33 A reaction is carried out in a PBR.
(a) Sketch the temperature and conversion profiles when the reaction is first
order (A -+ B) exothermic, irreversible and is carried out adiabatically
with no inerts. With a dashed line and a dotted line, show the profiles
when a moderate (dashed) and very large (dotted) amount of inerts are
added to the system. Make a plot of the exit conversion as a function of
the amount of inerts added, Le. X vs, 0,.
(b) Repeat part (a) for the case when the reaction is reversible, also sketch
the equilibrium conversion as a function of distance down the reactor.
(c) Repeat parts (a) and (b) when the reaction is endothermic.
(d) Repeat parts (a) through (c) when the reaction is second order
(A + B -+ C +D)
What differences do you observe when comparing your plots of the exit
conversions as a function of .
P8-34 Compare the profiles in Figures E8-6.1 (p. 457), E8-7.1 (p. 466), E8-7.3 (p.
468), 8-12 (p. 477), E8-10.1 (p. 489), E8-11.1 (p. 503), and E8-11.2 (p. 504).
(a) If you were to classify the profiles into groups, what would they be?
What are the comfilon characteristics of each group?
(b) What are the similarities and differences in the profiles in the various
groups and in the various figures?
(c) Describe why Figure E8-7.3 (p. 468) and Figure E8-6.1 (p. 457) look the
way they do. What are the similarities and differences? Describe qualita-
tively how they would change if inerts were added.
(d) Repeat (c) for Figure 8-12 (p. 477) and for Figure E8-10.1 (p. 489).
(e) Repeat (c) for Figure E8- 11,l (p. 503) and for Figure E8-11.2 (p. 504).
P8-35A Load the Intemctive Computer Module (ICM) from the CD-ROM. Run the module
and then md your perfoxmance number for the module which indicates your mas-
tering of the material. Your professor has the key to decode your performance number.
(a) ICM Heat Effects 1 Performance #
(b) ICM Heat Effects 2 Performance #

JOURNAL CRITIQUE PROBLEMS
P8C-1 Equation (8) in an article in J. Chem. Technol. Biotechnol., 31, 273 (1981) is
the kinetic model of the system proposed by the authors. Starting from Equa-
tion (2), derive the equation that describes the system. Does it agree with Equa-
tion (8)? By using the data in Figure l, determine the new reaction order. The
data in Table 2 show the effect of temperature. Figure 2 illustiates this effect.
Use Equation (8) and Table 2 to obtain Figure 2. Does it agree with the article's
results? Now use Table 2 and your equation. How does the figure obtained
compare with Figure 2? What is your new E,, ?
P8C-2 The kinetics of the reaction of sodium hypochlorite and sodium sulfate were
studied by the flow thermal method in Ind. Eng. Chem. Fundam., 19, 207
(1980). What is the flow thermal method? Can the energy balance developed in
this article be applied to a plug-flow reactor, and if not, what is the proper
energy balance? Under what conditions are the author's equations valid?
P8C-3 In an article on the kinetics of sucrose inversion by invertase with multiple
steady states in a CSTR [Chem. Eng. Commun., 6, 151 (198011, consider the
following challenges: Are the equations for K, and K,,, correct? If not, what are
the correct equations for these variables? Can an analysis be applied to this sys-
tem to deduce regions of multiple steady states?