isomerization of n-hexane supported platinum ... · the comparison of two classes of bifunctional...
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The comparison of two classes of bifunctional SBA-15 supported platinum-heteropolyacid catalysts for the isomerization of n-hexane
Teresa Pinto,a Philippe Arquillière,a Gerald P. Niccolai,b Frédéric Lefebvre*,a and Véronique Dufaud*,a
Supporting Information for New Journal of Chemistry
List of contents
Table S1. Platinum atomic content of Pt/SBA-15 determined by EDX.
Table S2. Apparent activation energy for bifunctional catalytic systems.
Figure S1. Low-angle XRD patterns of (a) pure SBA-15, (b) Pt/SBA-15, (c) HSiW/Pt/SBA-15 and (d) HSiW/SBA-15.
Figure S2. Wide-angle XRD patterns of (a) Pt/SBA-15, (b) HSiW/Pt/SBA-15 and (c) HSiW/SBA-15.
Figure S3. Nitrogen adsorption-desorption isotherms of (a) pure SBA-15, (b) Pt/SBA-15, (c) HSiW/SBA-15 and (d) HSiW/Pt/SBA-15.
Figure S4. FT-IR spectra of (a) pure SBA-15, (b) Pt/SBA-15, (c) HSiW/SBA-15, (d) HSiW/Pt/SBA-15 and (e) bulk H4SiW12O40.
Figure S5 Infrared spectra of pyridine desorption from HSiW/SBA-15.
Figure S6. HRTEM image and particle size distribution of Pt/SBA-15.
Figure S7. Representative HRTEM images and particle size distribution of HSiW/Pt/SBA-15.
Figure S8. HRTEM image and Fourier transform diffraction pattern of Pt/SBA-15 and comparison between d spacing and angle with face-centered Pt cubic structure.
Figure S9. (a) Conversion of n-hexane as a function of reaction time and (b) selectivity to C6 isomers as a function of the conversion for (HSiW/SBA-15 + Pt/SBA-15).
Figure S10. Evolution of the C6 products as a function of temperature.
Figure S11. Evolution of the C6 products as a function of flow rate.
Figure S12. Low-angle (left) and wide-angle (right) XRD patterns of (HSiW/SBA-15 + Pt/SBA-15) after catalysis.
Figure S13. Low-angle (left) and wide-angle (right) XRD patterns of HSiW/Pt/SBA-15 (a) before and (b) after catalysis.
Figure S14. FT-IR spectra after catalysis of (a) (HSiW/SBA-15 + Pt/SBA-15) and (b) HSiW/Pt/SBA-15.
Figure S15. Representative HRTEM micrographs of (HSiW/SBA-15 + Pt/SBA-15) after catalysis.
Figure S16. Representative HRTEM image of HSiW/Pt/SBA-15 after catalysis.
Electronic Supplementary Material (ESI) for New Journal of Chemistry.This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2015
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I. Catalysts characterization
Figure S1. Low-angle XRD patterns of (a) pure SBA-15, (b) Pt/SBA-15, (c) HSiW/Pt/SBA-15 and
(d) HSiW/SBA-15.
10 20 30 40 50 60 70
Inte
nsity
(a.
u.)
2θ (°)
(a)
(b)
(c)
Figure S2. Wide-angle XRD patterns of (a) Pt/SBA-15, (b) HSiW/Pt/SBA-15 and (c)
HSiW/SBA-15.
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0
0,1
0,2
0,3
0,4
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0,6
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2 7 12 17
Pore
Vol
ume
(cm
³/g·
nm)
Pore diameter (nm)
(c)
(b)
(a)
(d)
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0 0,2 0,4 0,6 0,8 1
Qua
ntity
Ads
orbe
d (c
m³/
g ST
P)
Relative Pressure (P/Po)
(a)
(b)
(c)
(d)
Figure S3. Nitrogen adsorption-desorption isotherms of (a) pure SBA-15, (b) Pt/SBA-15, (c)
HSiW/SBA-15 and (d) HSiW/Pt/SBA-15.
400500600700800900100011001200Wavenumbers (cm-1)
Abs
orba
nce
(a.u
.)
(a)
(b)
(c)
(d)
(e)
SiO(1090)
SiO (800)SiO (465)
W-Oc-W(790)
Si-Oa(928)
W-Od(978)
W-Ob-W(880)
Figure S4. FT-IR spectra of (a) pure SBA-15, (b) Pt/SBA-15, (c) HSiW/SBA-15, (d)
HSiW/Pt/SBA-15 and (e) bulk H4SiW12O40.
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Figure S5. Infrared spectra of pyridine on HSiW/SBA-15, (a) adsorption at room temperature and as a function of the desorption temperature (b) room temperature, (c) 50 °C, (d) 100 °C, (e) 150 °C and (f) 200 °C.
Figure S6. HRTEM image and particle size distribution of Pt/SBA-15. The number-average Pt particle size was obtained by counting 200 particles.
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Table S1. Platinum atomic content of Pt/SBA-15 determined by EDX (0.8 %wt Pt 0.25 atom Pt per 100 atom Si).
Sampling Si Pt
1 100 0.30
2 100 0.36
3 100 0.21
4 100 0.24
Figure S7. Representative HRTEM images and particle size distribution of HSiW/Pt/SBA-15. The number-average Pt particle size was obtained by counting 200 particles.
Figure S8. HRTEM image and Fourier transform diffraction pattern of Pt/SBA-15 and comparison between d spacing and angle with face-centered Pt cubic structure.
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II. n-Hexane isomerization
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Con
vers
ion
(%)
Reaction time (h)
0102030405060708090
100
0 20 40 60 80
Sele
ctiv
ityto
C6
isom
ers(
%)
Conversion (%)
Figure S9. Conversion of n-hexane as a function of reaction time (left) and selectivity to C6 isomers as a function of the conversion (right) for (HSiW/SBA-15 + Pt/SBA-15). Conditions: 1 bar, 200 °C, 5 mL.min-1 hydrogen flow, hexane/hydrogen ratio = 0.25, 1 g catalyst (0.5 g of each monofunctional catalyst).
Table S2. Apparent activation energy for bifunctional catalytic systems.
Catalyst Activation energy [kJmol-1] R2
HSiW/SBA-15 + Pt/SBA-15 66 0.99
HSiW/Pt/SBA-15 72 0.98
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Figure S10. Evolution of the C6 products as a function of temperature for the multiphase (HSiW/SBA-15 + Pt/SBA-15, dashed lines) and monophase (HSiW/Pt/SBA-15, dotted lines) bifunctional catalysts and comparison with the theoretical thermodynamic values (solid lines).1 Products are color coded in the graph: n-hexane, green; 2-methyl pentane, dark blue; 3-methyl pentane, light blue; 2,2-dimethybutane, brown; 2,3-dimethybutane, red.
Figure S11. Evolution of the C6 products as a function of flow rate for the multiphase bifunctional catalyst (HSiW/SBA-15 + Pt/SBA-15).
1 R. A. Alberty, Chem. Eng. Sci., 1987, 42, 2325.
7%conv.
13%conv.
37%conv.
63% conv.
9% conv.
29% conv.
55% conv.
120 130 140 150 160 170 180 190 200 210 2200
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Temperature (°C)
Per
cent
age
of C
6 pr
oduc
ts
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n-hexane2-methyl pentane3-methyl pentane2,3-dimethyl butane2,2-dimethyl butane
Flow Rate (ml/min)
Mol
ar fr
actio
n of
C6
prod
ucts
(%)
Thermodynamicequilibrium
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III. Catalysts characterization after catalysis
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Inte
nsity
2θ (°)
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10 20 30 40 50 60 70
Inte
nsity
2θ (°)
Figure S12. Low-angle (left) and wide-angle (right) XRD patterns of (HSiW/SBA-15 + Pt/SBA-15)
after catalysis (3 days on stream).
0,5 1,5 2,5 3,5 4,5 5,5 6,5
Inte
nsity
(a.u
.)
2θ (°)
(a)
(b)
10 20 30 40 50 60 70
Inte
nsity
(a.
u.)
2θ (°)
(a)
(b)
Figure S13. Low-angle (left) and wide-angle (right) XRD patterns of HSiW/Pt/SBA-15 (a) before
and (b) after catalysis (3 days on stream).
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400500600700800900100011001200Wavenumbers (cm-1)
Abs
orba
nce
(a.u
.)
(a)
(b)
SiO
SiOSiO
W-Oc-W(790)
Si-Oa
W-Od(978)
W-Ob-W(880)
Figure S14. FT-IR spectra after catalysis (3 days on stream) of (a) (HSiW/SBA-15 + Pt/SBA-15)
and (b) HSiW/Pt/SBA-15.
05
10152025303540
0 2 4 6 8 10 12
Cou
nt
Diameter (nm)
Experimental data
Log-normal fit( particles)
Figure S15. Representative HRTEM micrographs of (HSiW/SBA-15 + Pt/SBA-15) after catalysis
(3 days on stream) (Average Pt particles size = 5.3 ± 1.7 nm).
02468
101214
0 2 4 6 8
Cou
nt
Diameter (nm)
Experimental data
Log-normal fit( particles)
Figure S16. Representative HRTEM image of HSiW/Pt/SBA-15 after catalysis (3 days on stream)
(Average Pt particles size = 2.3 ± 0.6 nm).