Biomedical Engineering Reference
In-Depth Information
Substituting Eqn (E16-3.6) into Eqn (E16-3.4) , we obtain
R
ln 1 f A
f A
E
=
DH R
r
T 0 ¼
C A0 f A
(E16-3.7)
m cat k 0
Q
C P
Eqn (E16-3.7) is the mathematical description of the ignition e extinction curve (for conver-
sion versus the feed temperature). We now find the parameters:
C A0 ¼ r A0
u A
M A r 0 ¼
0:3
210 g
cm 3
¼ 1:21410 3 mol
cm 3
M A ¼
mol 0:85 g
=
=
=
2:010 5 J
DH R
r
=
mol
cm 3 1:21410 3 mol
cm 3
C A0 ¼
=
¼ 163:26 K
C P
1:75 J
g $ K Þ0:85 g
=
1:310 11 cm 3
m cat k 0
Q ¼
h $ g-cat Þ20 g-cat
¼ 8:66610 10
0:5 cm 3
=
min 60 min
=
h
Substituting these know parameters into Eqn (E16-3.7) , we obtain
16; 300
25:1853þ ln 1 f A
f A
T 0 ¼
163:26 f A
(E16-3.8)
which has a unit of Kelvin.
Eqn (E16-3.8) is plotted in Fig. E16-3.1 (by varying f A between 0 and 1, we computed
values of T 0 , and then graphing the data out to yield Fig. E16-3.1 ). One can observe that there
are multiple values of conversion f A for some given values of feed temperature T 0 (between
554.10 and 581.12 K).
1.0
0.8
0.6
0.4
0.2
0.0
500
520
540
560
580
600
620
640
T 0 , K
FIGURE E16-3.1 Variation of conversion with feed temperature.
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