Transcript Kein Folientitel

INGAS INtegrated GAS Powertrain
Politecnico di Milano
Dipartimento di Energia
Research Activities Nov 2009-May 2010
at Laboratory of Catalyis and Catalytic Processes
Gianpiero Groppi, Pio Forzatti, Djamela Bounechada, Paola Castellazzi
INGAS 18th month meeting, Paris, May 20-21 2010
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INGAS INtegrated GAS Powertrain
OUTLINE
• Powder catalysts
– Lean vs stoichiometric conditions
– S-poisoning / regeneration behaviour
• ECOCAT honeycomb catalyst
– Kinetic tests under T-ramp, constant l conditions
 l-sweep vs constant l
- Hydrothermal ageing and S-poisoning
INGAS 18th month meeting, Paris, May 20-21 2010
2SPB2
INGAS INtegrated GAS Powertrain
Lean vs stoichiometric conditions
CH4 0.5%; O2 4%; H2O 1%; He/Ar; 93.5%;
CH4 0.5%; O2 1%; H2O 1%; He/Ar; 93.5%;
T: 350°C, GHSV = 150.000 Ncm3/gcat/h
T: 350°C, GHSV = 150.000 Ncm3/gcat/h
100
100
Stoichiometric @ T=350°C
Ecocat
2% Pd/La2O3-Al2O3
80
60
40
Ecocat
2% Pd/La2O3-Al2O3
2% Pd/CeO2-Al2O3
20
2% Pd/Al2O3
% CH4 Conversion
% CH4 Conversion
lean @ 350°C
2% Pd/CeO2-Al2O3
80
2% Pd/Al2O3
2% Pd/ZrO2
60
40
20
2% Pd/ZrO2
0
0
0
2000
4000
6000
Time (s)
8000
0
2000
4000
6000
8000
Time (s)
Assessment of conversion performances depending on support and Pd load:
Upon activation the investigated Pd supported systems exhibit lower CH4 conversion
performaces than the reference Ecocat catalyst, but at 1/3 Pd load (2% w/w vs 6.3% w/w)
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INGAS INtegrated GAS Powertrain
S-poisoning on powder catalysts
CH4 0,5% ; H2 0,33%; O2 1,17%; H2O 5%; SO2 55 ppm; N2 at balance
T = 300°C for 6 h;
GHSV : 22500 Ncm3/gcat/h
ECOCAT
2% Pd/Al2O3
60
2% Pd/CeO2-Al2O3
50
2% Pd/La2O3-Al2O3
0.8 g
2% Pd/ZrO2
SO2 out (ppm)
Catalysts
40
30
20
10
Adsorbed SO2
(µmol)
ECOCAT
190
2% Pd/Al2O3
278
2% Pd/CeO2-Al2O3
235
2% Pd/La2O3-Al2O3
264
2% Pd/ZrO2
76
0
0
3600
7200 10800 14400 18000 21600
Time (s)
INGAS 18th month meeting, Paris, May 20-21 2010
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POLITECNICO DI MILANO
DIPARTIMENTO DI ENERGIA - LCCP
INGAS INtegrated GAS Powertrain
T-step regeneration procedure
900
Temperatura (°C)
800
700
600
500
400
GC
GC
GC
5000
10000
300
0
GC
GC
15000
20000
GC
25000
30000
Tempo (s)
Regeneration treatments performed at different T-steps
Activity measurements made at 350°C (lean)
INGAS 18th month meeting, Paris, May 20-21 2010
INGAS INtegrated GAS Powertrain
Regeneration under lean conditions
Lean conditions: 0.5% CH4, 4% O2, 1.1% H2O, 2% N2, He at balance
100
2% Pd/Al2O3
90
2% Pd/CeO2-Al2O3
2% Pd/La2O -Al2O3
CH4 conversion (%)
80
2
2% Pd/ZrO2
70
2% Pd/ZrO2
60
50
40
30
20
10
0
pre
post
poisoning poisoning
450°C
550°C
650°C
750°C
850°C
Ecocat reference catalyst exhibits higher resistance to S poisoning, catalyst supported on non
sulphating ZrO2 shows the worst behavior.
Only Pd/ZrO2 is significantly regenerated under lean conditions @ 750 °C
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INGAS INtegrated GAS Powertrain
Regeneration under rich pulses conditions
Alternated lean combustion (0.5% CH4, 4% O2, 1.1% H2O, 2% N2, He at balance) – reducing
pulses (0.5% CH4, 1.1% H2O, He at balance)
100
90
2% Pd/Al2O3
80
2% Pd/La2O -Al2O3
70
2% Pd/ZrO2
2% Pd/CeO2-Al2O3
CH4 conversion (%)
2
ECOCAT
60
50
40
30
20
10
0
pre
post
poisoning poisoning
400°C
450°C
500°C
550°C
600°C
Much more effective regeneration obtained under rich conditions (below 600°C)
Regeneration behaviour almost independent on the support
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INGAS INtegrated GAS Powertrain
SO2 release in TPR experiments
TPR: 0.5% CH4, 1.1% H2O, He at balance,
15°C/min up to 900°C
100
TPR
90
SO2 released (%)
80
1500
2% Pd/ZrO2
1200
2% Pd/Al2O3
2% Pd/CeO2-Al2O3
900
60
50
Pd/ZrO2
40
30
Pd/CeO2-Al2O3
20
Pd/Al2O3
10
Pd/La2O3-Al2O3
0
0
750
1500 2250 3000 3750 4500 5250
Tempo (s)
100
600
90
300
0
100
200
300
400
500
600
T (°C)
700
800
900
SO2 released (%)
SO2 (ppm)
2% Pd/La2O3-Al2O3
70
TPR
80
70
60
50
40
Pd/ZrO2
30
Pd/CeO2-Al2O3
20
Pd/Al2O3
10
Pd/La2O3-Al2O3
0
200
300
400
500
600
700
800
900
1000
T (°C)
INGAS 18th month meeting, Paris, May 20-21 2010
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INGAS INtegrated GAS Powertrain
Honeycomb sample: Experimental setup
36 cm
1.63 cm
15.2 cm
15.2 cm
1.3 cm
Sliding termocouple in a channel of the
monolith for the measurement of T axial profile
CH4
1500 ppm
CO
0.6 Vol.%
H2
0.1 Vol.%
NO
1300 ppm
500
O2
0.58/0.95
Vol.%
450
H2O
10 Vol.%
CO2
10.7 Vol.%
N2
balance
Lambda
1.00/1.02
GHSV
50000 h-1
650
flow
Tave= 11°C
600
Temperature [°C]
Standard feed gas mixture:
550
400
350
-1
GHSV=50000h
-1
GHSV=75000h
-3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12
z [mm]
INGAS 18th month meeting, Paris, May 20-21 2010
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INGAS INtegrated GAS Powertrain
Kinetic study under T-ramp experiments
100
T ramp (cooling)
λ = 1.02
O2 effect:
0.77% O2 (l=1,01)
80
100
CH4 conversion [%]
CH4 conversion [%]
0.95% O2 (l=1,02)
CO2 effect:
60
40
20
0
200 250 300 350 400 450 500 550 600
17,5% H2O
CH4 Conversion [%]
80
40
20
250
300
DB2.4
0% H2O
 EoxCH
4
roxCH4  k oxCH4  exp 
R

koxCH4 @ 773K
20
[mol/gcat/s/atm]
250
300
400
450
500
550
600
H2O effect:
10% H2O
40
0
200
350
Tmonolith [°C]
5% H2O
60
5,35% CO2
60
0
200
Tmonolith [°C]
100
80
10,7% CO2
350
400
450
Tmonolith [°C]
500
INGAS 18th month meeting, Paris, May 20-21 2010
550
600
EoxCH4 [kJ/mole]
1
  1
 T Trif

 w
  PCH [mol/g /s]
4
cat


1.53E-03
106.5
INGAS INtegrated GAS Powertrain
Reproducibility/stability at constant l
λ=1.00-1.01-1.02
T ramp (cooling)
λ = 1.02
100
80
70
60
50
40
30
20
10
0
200
T=500°C
90
CH4 conversion [%]
CH4 Conversion [%]
90
100
1st day
4th day
7th day
80
70
60
50
40
30
O2 = 0.95 % (l=1.02)
20
O2 = 0.77 % (l=1.01)
10
250
300
350
400
450
500
Tmonolith [°C]
INGAS 18th month meeting, Paris, May 20-21 2010
550
600
0
O2 = 0.57 % (l=1.00)
0
5
10
15
20
25
30
Time [min]
11
INGAS INtegrated GAS Powertrain
Reproducibility stability under λ-sweep
T = 350°C
100
80
70
60
50
40
30
20
10
0
0
3
6
9
12
15
18
Time [min]
21
24
27
30
60
50
40
30
20
t = 20s
0
3
6
9
15
18
21
24
27
30
T = 600°C
100
T = 500°C
12
Time [min]
90
CH4 conversion [%]
CH4 conversion [%]
70
0
90
80
70
60
50
40
30
20
Sample 4
Sample 5
Sample 6
10
0
3
6
18th
80
70
60
50
40
30
20
Sample 4
Sample 5
Sample 6
10
9
12
15
18
21
24
27
30
Time [min]
INGAS
80
10
100
0
Sample 4
Sample 5
Sample 6
90
CH4 conversion [%]
CH4 conversion [%]
90
T = 400°C
100
Sample 4
Sample 5
Sample 6
month meeting, Paris, May 20-21 2010
0
0
3
6
9
12
15
18
Time [min]
21
24
27
30
12
INGAS INtegrated GAS Powertrain
First order kinetic
r  k  CCH 4
dCCH 4
Qtot
 r
dVcat
• First order kinetic
• PFR balance
 E  773
kkin  k0 exp att  1 

RT
T



 k app ,theo  k app ,exp 

min


k app ,exp


Experimental
7
regression
6
6
4
1
0,00110
Th 

kapp ,theo    kkin
2
Arrhenius
From λ-sweep:
Experimental
Regression
5
ln(kapp)
ln(kapp)
5
2


8
7
3

k kin
Deff
  W 
Arrhenius
From T-ramp:
 Q

ln(kapp ,exp )  ln  tot  ln 1   CH 4 
 Vcat

Eatt = 120 kJ/mol
att =
k0 =E67
s-1125 kJ/mol
k0 = 70 s-1
4
3
2
1
0,00115
0,00120
0,00125
0,00130
0,00135
1/T
INGAS 18th month meeting, Paris, May 20-21 2010
0,00140
0,00145
0
0,00120
Eatt = 120 kJ/mol
= 135s-1kJ/mol
k0E=att1450
k0 = 2066 s-1
20 fold activity enhancement!
30 fold activity enhancement!
0,00130
0,00140
0,00150
0,00160
1/T
13
INGAS INtegrated GAS Powertrain
Effect of frequency on λ-sweep
100
80
70
90
CH4 conversion [%]
CH4 conversion [%]
90
60
50
40
30
20
80
70
60
50
40
30
20
10
10
0
T = 400°C
t=60s
t=20s
t=10s
t=5s
100
T = 350°C
t=60s
t=20s
t=10s
t=5s
0
3
6
9
12
15
18
21
24
27
0
30
0
3
6
9
T = 500°C
100
18
21
24
27
30
90
80
CH4 conversion [%]
CH4 conversion [%]
15
T = 600°C
100
90
70
60
50
40
30
t=60s
t=20s
t=10s
t=5s
20
10
0
12
Time [min]
Time [min]
0
3
6
80
70
60
50
40
30
t=60s
t=20s
t=10s
t=5s
20
10
9
12
15
18
21
24
27
Time [min]
INGAS 18th month meeting, Paris, May 20-21 2010
30
0
0
3
6
9
12
15
18
21
24
27
30
Time [min]
14
INGAS INtegrated GAS Powertrain
Effect of frequency on λ-sweep
0,6
t=60s
t=20s
t=10s
t=5s
0,5
CO molar fraction [%]
CO molar fraction [%]
0,5
0,4
0,4
0,3
0,3
0,2
0,2
0,1
0,1
0,0
0
3
6
9
12
15
18
21
24
27
T = 500°C
0,4
0,3
0,2
0,1
3
6
9
12
15
18
Time [min]
21
24
INGAS 18th month meeting, Paris, May 20-21 2010
27
30
6
9
12
15
18
21
24
27
30
T = 600°C
t=60s
t=20s
t=10s
t=5s
0,5
0,4
0,3
0,2
0,1
0,0
0
3
0,6
t=60s
t=20s
t=10s
t=5s
0,5
0
Time [min]
CO molar fraction [%]
CO molar fraction [%]
0,6
0,0
CO molar
fraction
30
Time [min]
0,0
T = 400°C
t=60s
t=20s
t=10s
t=5s
0,6
T = 350°C
0
3
6
9
12
15
18
Time [min]
21
24
27
30
15
INGAS INtegrated GAS Powertrain
Effect of frequency on λ-sweep
0,6
T = 350°C
t=60s
t=20s
t=10s
t=5s
0,5
H2 molar fraction [%]
H2 molar fraction [%]
0,5
0,4
0,4
0,3
0,3
0,2
0,2
0,1
0,0
0,1
0
3
6
9
12
15
18
21
24
27
30
Time [min]
H2 molar
fraction
0,0
H2 molar fraction [%]
H2 molar fraction [%]
0,4
0,3
0,2
0,1
0
3
6
9
12
15
18
3
21
24
Time [min]
INGAS 18th month meeting, Paris, May 20-21 2010
27
30
6
9
12
15
18
21
24
27
30
T = 600°C
0,6
t=60s
t=20s
t=10s
t=5s
0,5
0
Time [min]
T = 500°C
0,6
0,0
T = 400°C
t=60s
t=20s
t=10s
t=5s
0,6
t=60s
t=20s
t=10s
t=5s
0,5
0,4
0,3
0,2
0,1
0,0
0
3
6
9
12
15
18
21
24
27
30
Time [min]
16
INGAS INtegrated GAS Powertrain
Time evolution of concentration profiles
λ-sweep
t = 60s
Molar fraction [%]
0,5
0,4
T=500°C
CH4
0,6
O2
0,5
H2
Molar fraction [%]
0,6
CO
0,3
0,2
O2
H2
CO
0,3
0,2
0,1
0,1
0,0
310
0,4
T=600°C
CH4
311
312
313
Time [min]
314
315
0,0
440
441
442
443
444
445
Time [min]
O2 balances show that both Pd and (partly) CeO2 are involved in the redox process
INGAS 18th month meeting, Paris, May 20-21 2010
INGAS INtegrated GAS Powertrain
Hydrothermal Ageing
Gas in
wool
Monolithic
catalyst
Gas out
thermocouple
quartz
Ageing I
• 10h @ 800°C
• Air, H2O ~ 10%
λ-sweep
t = 20s
T = 500°C
T = 550°C
T = 450°C
CH4 conversion [%]
90
80
T = 600°C
70
60
T = 400°C
50
40
30
20
T = 350°C
10
0
T = 300°C
0
3
6
9 12 15 18 21 24 27 30 33 36 39
Time [min]
INGAS 18th month meeting, Paris, May 20-21 2010
After Ageing II
100
90
CH4 conversion [%]
After Ageing I
100
Ageing II
• 10h @ 950°C
• Air, H2O ~ 10%
80
60
T = 500°C
T = 550°C
T = 600°C
50
T = 450°C
70
40
30
20
T = 400°C
10
0
T = 350°C
T = 300°C
0
3
6
9 12 15 18 21 24 27 30 33 36 39
Time [min]
18
INGAS INtegrated GAS Powertrain
Hydrothermal Ageing
T = 350°C
100
after Degreening
after Ageing I
after Ageing II
80
70
60
50
40
30
20
80
70
60
50
40
30
20
10
10
0
after Degreening
after Ageing I
after Ageing II
90
CH4 conversion [%]
CH4 conversion [%]
90
T = 400°C
100
0
0
3
6
9
12
15
18
21
24
27
30
0
3
6
9
Time [min]
T = 500°C
90
90
80
80
70
60
50
40
30
after Degreening
after Ageing I
after Ageing II
20
10
0
0
3
6
9
12
18
21
24
27
30
60
50
40
30
after Degreening
after Ageing I
after Ageing II
20
0
15
18
70
10
Time [min]
15
T = 600°C
100
CH4 conversion [%]
CH4 conversion [%]
100
12
Time [min]
21
24
INGAS 18th month meeting, Paris, May 20-21 2010
27
30
0
3
6
9
12
15
18
Time [min]
21
24
27
30
19
INGAS INtegrated GAS Powertrain
Ageing with sulfur
Short ageing with sulfur (1gS/lcat)
Long ageing with sulfur (3gS/lcat)
•
1h @ 300°C
•
3h @ 300°C
•
Standard mixture (without NO) +
14ppm SO2
•
Standard mixture (without NO) +
14ppm SO2
SO2 in
16
14
12
SO2 [ppm]
SO2 [ppm]
SO2 out
14
12
10
10
8
6
8
6
4
4
2
2
0
SO2 in
16
SO2 out
0
10 20 30 40 50 60 70 80 90 100
Time [min]
Integral:
• SO2,in = 1.01 gS/lcat
• SO2,ads = 81%
INGAS 18th month meeting, Paris, May 20-21 2010
0
0
30
60
90
120
Time [min]
150
180
210
Integral:
• SO2,in = 2.99 gS/lcat
• SO2,ads = 73%
20
INGAS INtegrated GAS Powertrain
Ageing with sulfur
T = 350°C
100
80
70
60
50
40
30
20
10
0
80
70
60
50
40
30
20
10
0
3
6
9
12
15
18
21
24
27
30
Time [min]
T = 500°C
100
0
CH4 conversion
0
90
80
80
70
60
50
40
Degreened
Short Sulfur Aged
Long Sulfur Aged
Regenerated
20
10
0
0
3
6
9
12
18
Time [min]
9
21
24
27
INGAS 18th month meeting, Paris, May 20-21 2010
30
12
15
18
21
24
27
30
21
24
27
30
T = 600°C
70
60
50
40
30
Degreened
Short Sulfur Aged
Long Sulfur Aged
Regenerated
20
10
15
6
100
90
30
3
Time [min]
CH4 conversion [%]
CH4 conversion [%]
Degreened
Short Sulfur Aged
Long Sulfur Aged
Regenerated
90
CH4 conversion [%]
CH4 conversion [%]
90
T = 400°C
100
Degreened
Short Sulfur Aged
Long Sulfur Aged
Regenerated
0
0
3
6
9
12
15
18
Time [min]
21
INGAS INtegrated GAS Powertrain
Ageing with sulfur
Short ageing with sulfur (1gS/lcat)
•
1h @ 300°C
•
Standard mixture (without NO) + 14ppm SO2
On aged (II) catalyst
On degreened catalyst
SO2 in
16
SO2 out
14
12
SO2 [ppm]
SO2 [ppm]
SO2 out
14
12
10
10
8
8
6
6
4
4
2
2
0
SO2 in
16
0
10 20 30 40 50 60 70 80 90 100
Time [min]
Integral:
• SO2,in = 1.01 gS/lcat
• SO2,ads = 81%
INGAS 18th month meeting, Paris, May 20-21 2010
0
0
10
20
30
40
50
60
70
80
90 100
Time [min]
Integral:
• SO2,in = 1.02 gS/lcat
• SO2,ads = 57%
22
INGAS INtegrated GAS Powertrain
Ageing with sulfur
T = 350°C
100
80
70
60
50
40
30
20
10
0
0
3
6
9
12
15
18
21
24
27
30
70
60
50
40
30
20
Time [min]
T = 500°C
0
CH4 conversion
90
90
80
80
70
60
50
40
30
20
after Ageing II
after short Sulfur Ageing
after Regeneration
10
0
3
6
9
12
15
0
3
9
21
24
27
Time [min]
INGAS 18th month meeting, Paris, May 20-21 2010
30
12
15
18
21
24
27
30
Time [min]
T = 550°C
70
60
50
40
30
20
after Ageing II
after short Sulfur Ageing
after Regeneration
10
18
6
100
CH4 conversion [%]
CH4 conversion [%]
80
10
100
0
after Ageing II
after short Sulfur Ageing
after Regeneration
90
CH4 conversion [%]
CH4 conversion [%]
90
T = 400°C
100
after Ageing II
after short Sulfur Ageing
after Regeneration
0
0
3
6
9
12
15
18
Time [min]
21
24
27
30
23
INGAS INtegrated GAS Powertrain
Effect of ageing procedures
100
CH4 Conversion [%]
90
80
λ-sweep
t = 20s
70
60
50
40
Degreened
Aged I
Aged II
short S-Aged (after Ageing II)
short S-Aged (after Degreening)
long S-Aged (after Degreening)
30
20
10
0
300
350
400
450
500
550
600
Tinlet [°C]
INGAS 18th month meeting, Paris, May 20-21 2010
24
INGAS INtegrated GAS Powertrain
Effect of regeneration
100
λ-sweep
t = 20s
CH4 Conversion [%]
90
80
70
60
50
40
30
Degreened
Aged II
short S-Aged (after Ageing II)
Regenerated (after short S-Ageing)
long S-Aged (after Degreening)
Regenerated (after long S-Ageing)
20
10
0
300
350
400
450
500
550
600
Tinlet [°C]
INGAS 18th month meeting, Paris, May 20-21 2010
25
INGAS INtegrated GAS Powertrain
Conclusions and future work
•
Al2O3 supported Pd catalyst show lower but comparable conversion performances than Ecocat
with 1/3 Pd load
•
All the catalyst suffer from S-poisoning, but Ecocat is much more resistant
•
Significant regeneration under rich conditions at 600°C
•
Operations under l-sweep conditions provide superior (more than one order of magnitude activity
enhancement) and more stable performances of Ecocat honeycomb catalyst
•
Ecocat catalyst resists to hydrothemal ageing at 800°C, but suffer from significant deactivation at
950°C
•
Ecocat catalyst show good resistence towards S-poisoning
•
•
Preparation and testing of Au/Pd catalysts
•
Higher Pd load (up to 6% w/w)
•
Kinetic tests under l-sweep conditions
INGAS 18th month meeting, Paris, May 20-21 2010