HO CHI MINH CITY UNIVERSITY OF TECHNOLOGY - VNU
OFFICE FOR INTERNATIONAL STUDY PROGRAM
FACULTY OF CHEMICAL ENGINEERING
CHEMICAL REACTION ENGINEERING (CH3347)
CLASS CC01—GROUP 2 --- SEMESTER 212
INSTRUCTOR: Ph.D. CHÂU NGỌC ĐỖ UYÊN
Student’s Name
Student’s ID
LÊ PHẠM NHÃ THY
1953016
LÊ NGỌC THẢO
1952123
ĐẬU NGUYỄN ANH THƯ
1952476
VŨ THỊ PHI YẾN
1952542
TRƯƠNG HẠNH THANH TUYỀN
1915806
LÝ THANH THUÝ VY
1852885
Ho Chi Minh city, 2022
SOLUTION
1−
( 0.01 −1
− = (0.04 ) −
1 = 0.04
{−1
2 = 0.01
−1
= 2 3 = 2000
)
0 = 100 ⁄
0
= 100 ⁄
=
1
2
=
0.04
=>
=
1 −
0.01
1−
− = (1 − ) −
1 0
2 0
(1− )
1
= 1 0 (1 −
) −
0
1−
= 1 0 [(1 −
) − ]
1−0.8
= 1 0 [(1 −
) − 0.8 ]
= 1 0 (1 − 1.25
)
=
∫
0
=
(− )
0
0
=> = 0.8 =
80%
0
=
2000
100
0
∫0
1 0 (1−1.25 )
= 100 ∫
0
0.04×100× (1−1.25 )
= 0.506 =
50.6%
SOLUTION
Half-life time: t1/2= 5.2 days
Mean residence time t= 30 days
0.693
k=
1/2
=
0.693
5.2
= 0.1333
−1
For Mixed Flow Reator:
1
1
=
=
= 0.2
1 + 1 + 0.1333 ×
30
0
Fraction of activity = 1 -
0
% of activity = 80%
= 1 – 0.2 = 0.8
SOLUTION
-r = 0.004 C – 0.01 C
A
A
R
V = 2m3 = 2000 liter
FA = 100 l/min ,
CA0 = 100 mmol/l = 0.1 mol/l
At equation :
X
=
−
/
0 0
+1
Ae
1
= = 4
2
XAe = 0.8 = 80%
Actual conversion
0
=
−
=
2000
100
=
0.04 − 0 .01
CA = CA0 (1-XA)
CR = CR0 + CA0 X
A
Substituting all values, we get XA = 0.072 = 7.2 %
5.9. A specific enzyme acts as catalyst in the fermentation of reactant A. At a given
enzyme concentration in the aqueous feed stream (25 liter/min) find the volume of plug
flow reactor needed for 95% conversion of reactant A (CA0 = 2 mol/liter). The kinetics of
the fermentation at this enzyme concentration is given by:
→
,
0.1
− = 1
+ 0.5 .
SOLUTION
0 = 25 min
( )
We already have {
0
= 2( )
= 95%
For the volume of plug flow reactor, we have this equation with = 0
From
− =
0.1
1+0.5
= 0 (1 − ) = 2 x (1-0.95)=0.1 (mol/l)
→ =−∫
0
0
0.1
=−∫
−
2
1 + 0.5
≈ 39.457
0.1
→ = 39.457 × 25 ( ) = 986.433(
)
min
5.10. A gaseous feed of pure A (2 mol/liter, 100 mol/min) decomposes to give a variety
of products in a plug flow reactor. The kinetics of the conversion is represented by
A → 2.5 (products), − = (10 −1 )
Find the expected conversion in a 22-liter reactor.
Solution
A → 2.5 (products) ⇒ Irreversible reaction
(
−1 ) (FIRST
− = (10 −1 ) ⇒ = 10
ORDER)
For this stoichiometry, A → 2.5 (products), the expansion factor is
=
2.5 − 1
= 1.5
1
We use the equation (5.8) in Handbook Chemical Reaction Engineering by Octave
Levenspiel:
We use equation (5.21):
⟺ ×
= −(1 + ) ln(1 − ) −
0
1
1
) × 22() ×
⟺10 (
× 2 ( ) = −(1 + 1.5) ln(1 − ) − 1.5 ×
100 ( )
⇒ = 0.8997
Example 3.9
The feed contains 20% mole inerts:
0.8A -> 0.4R + 0.4S
0.2 inerts -> 0.2 inerts
=> εA =
(0.8+0.2)−(0.8+0.2)
=0
0.8+0.2
pA0 = 0.8P0 = 0.8 x 1 = 0.8 (atm) at t0 = 20 (s)
C
=
A0
0
0.8 ()
= 0.082 (.) × (100+273)() = 0.026 (
.
)
Calculate τ:
0
=
0
τ = tf – t0 =
0
0
=
208() × 0.026 ( )
1
100×
( )
3600
= 194.69 (s) ≈ 195 (s)
tf = τ + t0 = 195 + 20 = 215 (s)
According to the data table, using interpolation, at t = 215 (s), pA = 0.125 (atm)
CA = 0.0041 (
)
For mixed flow reactor with εA = 0:
-rA =
τ=
0−
0
−
=
0.026 − 0 .0041 ( )
=> XA =
XA = 84%.
195 ()
×(− )
0
= 1.12 x 10-4 (
.
)
−4
195() × (1.12×10 )(
. )
=
=
0.026 ( )
0.84