Efficiency by design when further reactions hinder selectivity ―― Question ► How do defects (porosity variations) of membranes may affect selectivity Approach ► CFD: computational fluid dynamics, 3D modeling of (cylindrical) membranes Impact ► Insight for « Standardization »: impact of longitudinal variations ≫ annular ones

2. Modelling of flow-through catalytic
membrane reactor for partial hydrogenation
reactions
USP | Laboratory for the Simulation and Control of
Processes (LSCP)
TUB | Reaction Engineering of Heterogeneous
Systems
Costa, I. S. Rangel, L. P. Park, S. W. Schomäcker, R.• • •

3. PROBLEM SET-UP
Selectivity | partial hydrogenation reactions
CHOICE OF A STRATEGY
Membrane reaction | active contactor mode
EXPERIMENTAL RESULTS
Increase of selectivity | model reaction
Project milestones
EXPERIMENTAL
RESEARCH
(PRECEDING WORK)
MODELLING &
SIMULATION
(PRESENT WORK)
PRE-PROCESSING
CFD | ANSYS Fluent
MODELLING ISSUES
Porous media | Turbulence
SIMULATION RESULTS
Membrane anisotropy | Effects on selectivity
3 / 26

4. Dr. Andrea SchmidtDr. Andrea Schmidt
Brief history
Prof. Reinhard Schomäcker
Prof. Song Won Park
Dr. Leonardo Rangel
M.Sc. Isis Santos Costa
4 / 26
(preceding work)

5. PROBLEM SET-UP
Selectivity | partial hydrogenation reactions
CHOICE OF A STRATEGY
Membrane reaction | active contactor mode
EXPERIMENTAL RESULTS
Increase of selectivity | model reaction
Project milestones
EXPERIMENTAL
RESEARCH
MODELLING &
SIMULATION
(PRESENT WORK)
PRE-PROCESSING
CFD | ANSYS Fluent
MODELLING ISSUES
Porous media | Turbulence
SIMULATION RESULTS
Membrane anisotropy | Effects on selectivity
5 / 26
(PRECEDING WORK)

6. Problem set-up
6 / 26
Model reaction: Hydrogenation of 1,5-cyclooctadiene
SELECTIVITY OF PARTIAL HYDROGENATION
How to
increase
selectivity?
(PRECEDING WORK)

7. PROBLEM SET-UP
Selectivity | partial hydrogenation reactions
CHOICE OF A STRATEGY
Membrane reaction | active contactor mode
EXPERIMENTAL RESULTS
Increase of selectivity | model reaction
Project milestones
EXPERIMENTAL
RESEARCH
(PRECEDING WORK)
MODELLING &
SIMULATION
(PRESENT WORK)
PRE-PROCESSING
CFD | ANSYS Fluent
MODELLING ISSUES
Porous media | Turbulence
SIMULATION RESULTS
Membrane anisotropy | Effects on selectivity
7 / 26
(PRECEDING WORK)

8. FBRMR
reagents
products
reagents
products
catalyst
catalyst
pellet
Increase of
selectivity
Choice of a strategy
8 / 26
Control over mass transport limitations
MEMBRANE REACTION | ACTIVE CONTACTOR MODE
(PRECEDING WORK)

9. Choice of a strategy
9 / 26
Testing bench
MEMBRANE REACTION | ACTIVE CONTACTOR MODE
Saturation
tank
Membrane
moduleGear pump
(PRECEDING WORK)

10. Choice of a strategy
10 / 26
Testing bench
MEMBRANE REACTION | ACTIVE CONTACTOR MODE
Aℓ2O3
Pd
(PRECEDING WORK)

11. PROBLEM SET-UP
Selectivity | partial hydrogenation reactions
CHOICE OF A STRATEGY
Membrane reaction | active contactor mode
EXPERIMENTAL RESULTS
Increase of selectivity | model reaction
Project milestones
EXPERIMENTAL
RESEARCH
(PRECEDING WORK)
MODELLING &
SIMULATION
(PRESENT WORK)
PRE-PROCESSING
CFD | ANSYS Fluent
MODELLING ISSUES
Porous media | Turbulence
SIMULATION RESULTS
Membrane anisotropy | Effects on selectivity
11 / 26
(PRECEDING WORK)

12. Experimental results
12 / 26
Schmidt, 2007 (PhD Thesis)
INCREASE OF SELECTIVITY | CYCLOOCTENE
REACTOR TYPE CONVERSION SELECTIVITY
Slurry 100% 95%
CMR 100% 94%
FBR 100% 45%
Comparable to virtually no transport limitation
Reaction conditions: 50°C, 10 bar H2, 200 mℓ/min
(PRECEDING WORK)

13. PROBLEM SET-UP
Selectivity | partial hydrogenation reactions
CHOICE OF A STRATEGY
Membrane reaction | active contactor mode
EXPERIMENTAL RESULTS
Increase of selectivity | model reaction
Project milestones
EXPERIMENTAL
RESEARCH
(PRECEDING WORK)
MODELLING &
SIMULATION
(PRESENT WORK)
PRE-PROCESSING
CFD | ANSYS Fluent
MODELLING ISSUES
Porous media | Turbulence
SIMULATION RESULTS
Membrane anisotropy | Effects on selectivity
13 / 26

14. Pre-processing
14 / 26
Computational domain
CFD | ANSYS FLUENT
Feature Magnitude
Internal diameter 1,9 mm
External diameter 2,9 mm
Active length 220 mm
Coated end (each) 15 mm
Average pore diameter 1,9 x µm
Wall thickness 0,5 x mm
Porosity 30%
Tortuosity 2,0

15. Pre-processing
15 / 26
Mesh generation
CFD | ANSYS FLUENT
High aspect
ratio

16. PROBLEM SET-UP
Selectivity | partial hydrogenation reactions
CHOICE OF A STRATEGY
Membrane reaction | active contactor mode
EXPERIMENTAL RESULTS
Increase of selectivity | model reaction
Project milestones
EXPERIMENTAL
RESEARCH
(PRECEDING WORK)
MODELLING &
SIMULATION
(PRESENT WORK)
PRE-PROCESSING
CFD | ANSYS Fluent
MODELLING ISSUES
Porous media | Turbulence
SIMULATION RESULTS
Membrane anisotropy | Effects on selectivity
16 / 26

17. Modelling issues
17 / 26
Chosen model: fixed bed | Ergun equation for pressure drop
POROUS MEDIA
( ) ( ) 2
33
2
2
175.11150

−
+
−
=

v
D
v
DL
p
pp 



viscous losses inertial losses
Termo de perda
viscosa






+−= iii vvCvS 


2
1
2
Termo de perda
inercial
viscous
losses
inertial
losses
( )2
32
1150 


−
= pD
( )
32
15.3

−
=
pD
C
Porosity = 30%
Dp = ?
Ergunequation

18. Modelling issues
18 / 26
Assessing model parameter Dp | software ImageJ
POROUS MEDIA
Particle diameter
Image surface: 7.739,400 mm²
Identified number of particles: 343
Estimated average particle diameter: Dp = 5,36 mm
Viscous porous
resistance (1/α)
9,5 e+13
m-2
Inertial porous
resistance (C2)
1,7 e+07

19. PROBLEM SET-UP
Selectivity | partial hydrogenation reactions
CHOICE OF A STRATEGY
Membrane reaction | active contactor mode
EXPERIMENTAL RESULTS
Increase of selectivity | model reaction
Project milestones
EXPERIMENTAL
RESEARCH
(PRECEDING WORK)
MODELLING &
SIMULATION
(PRESENT WORK)
PRE-PROCESSING
CFD | ANSYS Fluent
MODELLING ISSUES
Porous media | Turbulence
SIMULATION RESULTS
Membrane anisotropy | Effects on selectivity
19 / 26

20. Simulation results
20 / 26
Simulation of the effects of membrane variance on flow and
reaction
MEMBRANE ANISOTROPY | EFFECTS ON SELECTIVITY
Case 1: simulation of membrane anisotropy with
maintenance of azimuthal uniformity along the
length
Case 2: simulation of membrane anisotropy affecting the
azimuthal uniformity along the length

21. Simulation results
21 / 26
Case 1: Definition
MEMBRANE ANISOTROPY | EFFECTS ON SELECTIVITY
Porosity = 40%
Porosity = 30%
Porosity = 30%
Porosity = 30%
Outflow

22. Simulation results
22 / 26
Case 2: Definition
MEMBRANE ANISOTROPY | EFFECTS ON SELECTIVITY
Same porosity
Different porosities

23. Simulation results
23 / 26
Results: case 1
MEMBRANE ANISOTROPY | EFFECTS ON SELECTIVITY
No detectable effect

24. Simulation results
24 / 26
Results: case 2
MEMBRANE ANISOTROPY | EFFECTS ON SELECTIVITY
Evident effect on the
flow pattern

25. Conclusions and perspectives
25 / 26
CONCLUSIONS
Small structural changes in membrane reactors can significantly impact
the flow profile, affecting the performance of the reactor.
Through the development CFD models and simulation, the relationship
between structure and performance of membrane reactors can be
studied comprehensively.
PERSPECTIVES
Development of a dynamic model, taking into account recirculation in the
whole reactor.
Extension to include reaction.
(PRESENT WORK)

26. Relevant references
26 / 26
CONSIDERED ON THE WORK
Koukou, M.K.; Papayannakos, N.; Markatos, N.C. (2001):
On the importance of non-ideal flow effects in the operation of
industrial-scale adiabatic membrane reactors
Department of Chemical Engineering, National Technical University of
Athens
Chemical Engineering Journal
RECENT
Minyukova, T. P.; Shtertser, N. V.; Khassin, A. A.; Yurieva, T. M. (2012):
Permeable composite membrane as a catalytically active contactor
for hydrogenation reactions
Boreskov Institute of Catalysis, Russia. Novosibirsk State University,
Russia
Catalysis Today
(PRESENT WORK)

27. Questions

29. 29
ISIS SANTOS COSTA