Biomedical Engineering Reference
In-Depth Information
fractional yield concept is useful. When numerical methods are used, the complexity
would not however deter a solution with today's computers.)
5.44. Under ultraviolet radiation, reactant A of C A0 ¼
10 kmol/m 3 in a liquid process stream
1m 3 /min) decomposes as follows:
( Q
¼
= m 3 $ min
r 1 ¼ 16C 0: A
A
/
R
kmol
= m 3 $ min
A
/
S
r 2 ¼ 12C A
kmol
= m 3
$ min
r 3 ¼ 0:5 C 2 A
2A
/
T
kmol
We wish to design a reactor setup to maximize the production R.
(a) What type of reactor or reactor scheme is to be selected?
(b) Calculate the fraction of feed transformed into the desired product R as well as the
volume of the reactor needed.
(c) Repeat a. and b. if the desired product is S instead.
5.45. The gas-phase decomposing reaction
; r ¼ kC A
is to be carried out adiabatically in a flow reactor. The feed consists of pure A at
a temperature of 298 K and a pressure of 1 bar. The feed rate is 0.1 mol/s. Neglect
the pressure drop in the reactor.
(a) Calculate the operating temperature and conversion from a CSTR of volume 2 m 3 .
(b) Calculate the volume of a PFR for a conversion of 0.99. Comment on your
findings.
(c) Recalculate the volume of the PFR for a conversion of 0.99, but the feed to the reactor
is preheated to 500 K.
The additional data are: k
A
/
B
þ
C
10 11 exp
s 1
E
R T
E
R ¼
¼
18000 K;
D
H R ¼
60 kJ/mol-A;
;
C PA ¼
120 J
mol $ K
Þ
; C PB ¼
80 J
mol $ K
Þ
; C PC ¼
40 J
mol $ K
Þ
5.46. Consider the elementary reaction: A
þ
R
/
2 R with a rate constant equal
$ s 1 . We wish to process 1.5 L/s of a feed containing 10 mol/L A to the
highest conversion possible in the reactor system consisting of four 150-L CSTR's
connected as you wish and any feed arrangement.
(a) Sketch your recommended design and feed arrangement.
(b) Determine the final conversion.
(c) Comment on the reactor start-up conditions.
5.47. We wish to convert A to R in a plug flow reactor by the aqueous decomposition
reaction:
0.001 L $ mol 1
A
/
R
þ
U
;
r 1 ¼ k 1 C A
1.2 m 3 /(mol $ min). We realized that A can also be dimerized to S:
A
where k 1 ¼
r 2 ¼ k 2 C 2 A
þ
A
/
S
;
40 mol/m 3 .
with k 2 ¼
0.8/min. The aqueous feed contains A by C A0 ¼
Search WWH ::




Custom Search