Reaction Engineering (re)
1
In the Model Builder window, under Component 1 click Reaction Engineering (re).
2
Locate the Reactor section in the Settings window.
3
From the Reactor type list, choose Plug flow.
4
Locate the Energy Balance section. From the list, choose Include, and type the Q_mem in the associated text field.
This accounts for the heat transferred into the reactor due to the flow across the membrane.
5
Click to expand the Mixture properties section. In the p text field, type p_reactor.
Reaction 1
1
On the Reaction Engineering toolbar, click Reaction .
2
In the Settings window for Reaction , locate the Reaction Formula section.
3
In the Formula text field, type C6H5CH3+H2=>C6H6+CH4 and click Apply.
4
Locate the Reaction Rate section. From the Reaction rate list, choose User defined.
Change the default kinetic expression by modifying the reaction order for hydrogen.
5
In the r text field, type
re.kf_1*re.c_C6H5CH3*(re.c_H2/1[mol/m^3])^0.5
Change the Forward volumetric overall reaction order to 1. The specification of the units are not strictly required. You could have typed in the concentration of hydrogen as is. The reason for specifying the unit is to use consistent units throughout the model. This makes it easier to spot errors in the model definition.
6
Locate the Rate Constants section, and select the Use Arrhenius expressions checkbox.
7
In the Af text field, type 5.67e9.
8
In the Ef text field, type 228.2e3.
Reaction 2
1
On the Reaction Engineering toolbar, click Reaction .
2
In the new reaction node, locate the Reaction Formula section.
3
Type C6H6<=>C12H10+H2 in the Formula text field and click Balance .
4
Under Rate Constants select the Use Arrhenius expressions checkbox and type in the following:
In the Af text field, type 1e8.
In the Ef text field, type 167.5e3.
In the Ar text field, type 1e8.
In the Er text field, type 149.8e3.
Additional Source 1
Add an Additional Source  feature to the Reaction Engineering interface  to model the mass flow of hydrogen across the membrane.
1
On the Reaction Engineering toolbar, click Additional Source .
2
Locate the Additional Rate Expression section in the Settings window.
3
In the Volumetric species table, add a source rate for the hydrogen species:
Species
Additional rate expression (mol/(m^3*s))
H2
f_H2
Initial Values 1
The plug-flow reactor requires conditions for the inlet temperature and inlet molar flow rate.
1
In the Model Builder window, click Initial Values 1  under Component 1 (comp1) > Reaction Engineering (re) .
2
In the Settings window, locate the General Parameters section, and type T_inlet in the T0,in text field.
3
Locate the Volumetric Species Initial Value section. In the table, enter the following settings:
Species
Molar flow rate (mol/s)
C6H5CH3
10
H2
10
Now, match all species in the Reaction Engineering interface  with the corresponding species in the created Vapor–Liquid System . For a coupled species, the functions for thermodynamic properties will automatically be created and added to the system. When all species in the Reaction Engineering interface  are matched (fully coupled), the properties of the reacting system (mixture heat capacity, mixture molar volume, and so on) will be calculated by the thermodynamic system.
1
In the Model Builder window, click Reaction Engineering (re) .
2
In the Settings window for Reaction Engineering , click to expand the Mixture properties section.
3
Select the Thermodynamics checkbox.
4
Locate the Species Matching section. In the table, enter the following settings:
Species
From Thermodynamics
C12H10
C12H10
C6H5CH3
C7H8
C6H6
C6H6
CH4
CH4
H2
H2