Reaction in an Isothermal Continuous Stirred-Tank Reactor (CSTR)

​
C
A
0
(mol/L)
0.5
volumetric flow rate (L/min)
30
reaction rate constant k (
-1
s
)
0.04
reaction order of A
st
1
nd
2
In this Demonstration, the liquid-phase reaction
A⟶B
takes place in an isothermal, continuous stirred-tank reactor (CSTR). Use the sliders to set the feed concentration of
A
,
C
A,0
, the volumetric flow rate and the rate constant
k
. Select the reaction order with respect to
A
using the "
st
1
" or "
nd
2
" button. The rate constant has the same numerical value when the reaction order changes, but its units are different. The figure shows the feed molar flow rate
F
A,0
, the feed concentration
C
A,0
, the outlet molar flow rates
F
A
,
F
B
and the outlet concentrations
C
A
,
C
B
. Note that the outlet concentrations are identical to the concentrations in the reactor. The reactor residence time
τ=V/v
is also calculated.

Details

The constant-density, liquid-phase reaction takes place in an isothermal CSTR:
AB
, with reaction rate
-
r
A
=
r
B
=k
m
C
A
,
where
C
A
is the concentration of component
A
,
r
i
is the rate of reaction of component
i
,
m
is the order of reaction with respect to
A
and
k
is the rate constant.
Mass balances on each component:
component
A
:
F
A,0
-
F
A
+
r
A
V=0
,
component
B
:
F
B,0
-
F
B
+
r
B
V=0
.
Mass balances in terms of volumetric flow rates and concentrations:
component
A
:
C
A,0
v-
C
A
v+
r
A
V=0
,
component
B
:
C
B,0
v-
C
B
v+
r
B
V=0
.
F
i,0
is the molar flow rate of component
i
at the inlet;
F
i
is the molar flow rate of component
i
at the outlet;
C
i,0
and
C
i
are molar concentrations of component
i
at the inlet and outlet, respectively;
and
v
is the volumetric flow rate, which is equal at the inlet and outlet for constant-density reactions.
The solution to these mass balances for first- and second-order reactions are:
first-order:
C
A
(τ)=
C
A,0
-
C
A,0
-kτ
e
C
B
(τ)=
C
B,0
+
C
A,0
-
C
A,0
-kτ
e

second-order:
C
A
(τ)=
C
A,0
-
-1
1
C
A,0
+kτ
,
where
τ=V/v
is the residence time in the reactor.

External Links

Multiple States in an Isothermal Continuous Stirred-Tank Reactor
Inhibition of Enzyme Reactions in Continuous Stirred-Tank Reactor and Batch Reactor
Operating a Chemostat (CSTR Bioreactor)
Minimized Volume for Reactors in Series
Reactor Design Economics
Continuous Stirred-Tank Reactor That Loses Cooling
Multiple Steady States in a Continuously Stirred Tank Reactor
Multiple Steady States in Continuous Stirred-Tank Reactor with Heat Exchange

Permanent Citation

Neil Hendren, John L. Falconer
​
​"Reaction in an Isothermal Continuous Stirred-Tank Reactor (CSTR)"​
​http://demonstrations.wolfram.com/ReactionInAnIsothermalContinuousStirredTankReactorCSTR/​
​Wolfram Demonstrations Project​
​Published: February 27, 2019