Supporting Information
Kinetic Modeling of Pt/C Catalyzed Aqueous Phase Glycerol Conversion with In
Situ Formed Hydrogen
Xin Jin1, Prem S. Thapa2, Bala Subramaniam1, Raghunath V. Chaudhari1*
1
Center for Environmentally Beneficial Catalysis, Department of Chemical and Petroleum Engineering,
University of Kansas, 1501 Wakarusa Drive, Lawrence, Kansas 66047, USA
2
Microscopy and Analytical Imaging Laboratory, Haworth Hall, 1200 Sunnyside Ave, University of
Kansas, Lawrence, Kansas 66045, USA
*To whom the correspondence should be addressed. E-mail: rvc1948@ku.edu
KEYWORDS Kinetic modeling, Polyol, Tandem catalysis, Dehydrogenation, Hydrogenolysis
1
(a)
(b)
Figure S1. (a) Temporal glycerol concentration profile at different temperatures, and (b) apparent first order
dependence (PN2: 1.4 MPa, glycerol: 1.1 kmol/m3, solvent: H2O, NaOH/glycerol molar ratio: 1.1, Pt/C catalyst
charge: 6.7 kg/m3)
Figure S2. Apparent activation energy for glycerol conversion on Pt/C catalyst
2
(a)
(b)
(c)
Figure S3. Arrhenius and van’t Hoff plots of rate and adsorption equilibrium constants on Pt/C catalyst
3
Figure S4. Concentration-time profiles of glycerol conversion on Pt/C catalyst at 130 oC with different initial
glycerol and NaOH concentration
4
Figure S5. Concentration-time profiles of glycerol conversion on Pt/C catalyst at 160 oC with different initial
NaOH concentration
5
1. Derivation of Models ii~vi
Table S1-1. Derivation of surface reactions in Model ii
No.
Surface reaction
Rate equation
r1 
r1
r2 
r2
r3 
r3
1  K
k s1  K gly  C gly  K OH   COH 
 C gly  K EG  CEG  K OH   COH  
2
gly
1  K
k s 2  K gly  C gly  K OH   COH 
 C gly  K EG  C EG  K OH   COH  
2
gly
k s 3  K1, 2PDO  C1, 2PDO  KOH   COH 
1  K
1, 2 PDO
r4 
r4
r5 
r5
r6 
r6
6
2
k s 4  K gly  C gly  K OH   C OH 
1  K
1  K
 C1, 2PDO 
 C gly  K EG  C EG  K OH   C OH  
2
gly
k s 5  K gly  C gly  K OH   C OH 
 C gly  K EG  C EG  K OH   C OH  
2
gly
1  K
k s 6  K EG  C EG  K OH   C OH 
 C gly  K EG  C EG  K OH   C OH  
2
gly
Table S1-2. Derivation of surface reactions in Model iii
No.
Surface reaction
Rate equation
r1 
r1
r2 
r2
r3 
r3
r4 
r4
r5 
r5
r6 
r6
7
k s1  K gly  C gly  COH 
1  K
gly
 C gly  K OH   COH 

2
k s 2  K gly  C gly  COH 
1  K
 C gly  K OH   COH  
2
gly
k s 3  K1, 2 PDO  C1, 2 PDO  COH 
1  K
 C1, 2 PDO 
2
1, 2  PDO
k s 4  K gly  C gly  COH 
1  K
 C gly  K OH   COH  
2
gly
k s 5  K gly  C gly  COH 
1  K
 C gly  K OH   COH  
2
gly
k s 6  K gly  C gly  COH 
1  K
gly
 C gly  K OH   COH 

2
Table S1-3. Derivation of surface reactions in Model iv
No.
Surface reaction
Rate equation
r1 
r1
r2 
r2
r3 
r3
1  K
1  K
k s1  K gly  Cgly  COH 
 Cgly  K EG  CEG   1  KOH   COH  
2
gly
k s 2  K gly  C gly  COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
k s 3  K1, 2PDO  C1, 2PDO  COH 
1  K
r4 
r4
r5 
r5
r6 
r6
8
1  K
1  K
1  K
 C1, 2PDO 
2
1, 2 PDO
k s 4  K gly  C gly  COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
k s 5  K gly  C gly  COH 
 C gly  K EG  C EG   1  K OH   C OH  
2
gly
k s 5  K EG  C EG  COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
Table S1-4. Derivation of surface reactions in Model v
No.
Surface reaction
Rate equation
r1 
r1
r2 
r2
r3 
r3
r4 
r4
r5 
r5
r6 
r6
9
1  K
k s1  K gly  C gly  K OH   COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
1  K
k s 2  K gly  C gly  K OH   COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
k s 3  K1, 2 PDO  C1, 2 PDO  K OH   COH 
1  K
1  K
1  K
1  K
 C1, 2 PDO 
2
1, 2  PDO
k s 4  K gly  C gly  K OH   COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
k s 5  K gly  C gly  K OH   COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
k s 5  K EG  C EG  K OH   COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
Table S1-5. Derivation of surface reactions in Model vi
No.
Surface reaction
Rate equation
r1 
r1
r2 
r2
r3 
r3
1  K
1  K
k s1  K gly  C gly  C OH 
 C gly   1  K OH   C OH  
2
gly
k s 2  K gly  C gly  COH 
 C gly   1  K OH   COH  
2
gly
k s 3  K1, 2PDO  C1, 2PDO  COH 
1  K
 C1, 2PDO 
2
1, 2 PDO
r4 
r4
r5 
r5
r6 
r6
10
1  K
1  K
1  K
k s 4  K gly  C gly  COH 
 C gly   1  K OH   COH  
2
gly
k s 5  K gly  C gly  COH 
 C gly   1  K OH   COH  
2
gly
k s 5  K gly  C gly  COH 
 C gly   1  K OH   COH  
2
gly
2. Data fitting for Models ii~vi
Table S2-1. Rate equations for Model ii
r1 
r2 
r3 
1  K
k s1  K gly  C gly  K OH   COH 
 C gly  K EG  CEG  K OH   COH  
2
gly
1  K
k s 2  K gly  C gly  K OH   COH 
 C gly  K EG  C EG  K OH   COH  
2
gly
k s 3  K1, 2PDO  C1, 2PDO  KOH   COH 
1  K
r4 
r5 
r6 
1  K
1  K
1  K
 C1, 2PDO 
2
1, 2 PDO
k s 4  K gly  C gly  K OH   C OH 
 C gly  K EG  C EG  K OH   C OH  
2
gly
k s 5  K gly  C gly  K OH   C OH 
 C gly  K EG  C EG  K OH   C OH  
2
gly
k s 6  K EG  C EG  K OH   C OH 
 C gly  K EG  C EG  K OH   C OH  
2
gly
Table S2-2. Parameter estimation for Model ii
Model ii
Constants
ks1
ks2
ks3×10-1
ks4
ks5
ks6×103
Kgly×10-2
KOH-×10-2
K1,2-PDO
KEG×10-3
130oC
145oC
160oC
44.0±3.17
20.0±1.66
3.76±0.89
3.68±0.43
<0
1.95±0.57
6.06
2.05
8.31±7.12
7.54
6.61±1.69
3.72±0.95
1.37±0.44
0.43±0.18
0.37±0.14
~0
14.2
14.5
27.0±29.4
25.5±22.8
14.3±1.48
1.29
28.9±5.83
0.56±0.07
3.49±0.26
~0
17.5
11.6
16.5
>>4000
11
Table S2-3. Rate equations for Model iii
r1 
r2 
r3 
r4 
r5 
r6 
k s1  K gly  C gly  COH 
1  K
gly
 C gly  K OH   COH 

2
k s 2  K gly  C gly  COH 
1  K
 C gly  K OH   COH  
2
gly
k s 3  K1, 2 PDO  C1, 2 PDO  COH 
1  K
 C1, 2 PDO 
2
1, 2 PDO
k s 4  K gly  C gly  COH 
1  K
 C gly  K OH   COH  
2
gly
k s 5  K gly  C gly  COH 
1  K
 C gly  K OH   COH  
2
gly
k s 6  K gly  C gly  COH 
1  K
gly
 C gly  K OH   COH 

2
Table S2-4. Parameter estimation for Model iii
Model iii
Constants
ks1
ks2×10-1
ks3×10-2
ks4×10-2
ks5×10-2
ks6×10-2
Kgly×10-2
KOH-×10-3
K1,2-PDO
130oC
145oC
160oC
1.33±0.10
6.05±0.53
6.47±0.96
6.75
9.77±1.67
3.42±1.61
3.80
1.00
0.38
1.98±0.16
10.8
24.8±3.37
11.7±1.5
24.4±1.68
>>600
3.75±0.22
~0
0.20
10.2±0.42
5.32
241±16.9
23.0±2.77
144±11.9
2105±194
2.93±1.23
5.70±26.5
2.65
12
Table S2-5. Rate equations for Model iv
r1 
r2 
r3 
1  K
k s1  K gly  Cgly  COH 
 Cgly  K EG  CEG   1  KOH   COH  
2
gly
1  K
k s 2  K gly  C gly  COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
k s 3  K1, 2PDO  C1, 2PDO  COH 
1  K
r4 
r5 
r6 
1  K
1  K
1  K
 C1, 2PDO 
2
1, 2 PDO
k s 4  K gly  C gly  COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
k s 5  K gly  C gly  COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
k s 5  K EG  C EG  COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
Table S2-6. Parameter estimation for Model iv
Model iv
Constants
ks1
ks2×10-1
ks3×10-2
ks4×10-2
ks5×10-2
ks6
Kgly×10-2
KOH-×10-3
K1,2-PDO
KEG×10-2
130oC
145oC
160oC
1.28±0.10
5.86±0.51
6.47±0.96
6.53
9.45±1.60
1.66
3.80
1.00
0.37
5.21±2.50
1.97±0.16
10.8
24.9±3.6
12.9±1.48
24.1±1.56
12.0
4.35±5.33
18.6±137
0.20
1.50±4.93
2.28±0.24
12.7±1.57
43.6±11.6
21.9±2.31
73.4
177
6.24±0.45
<0
0.11
1.14±2.00
13
Table S2-7. Rate equations for Model v
r1 
r2 
r3 
r4 
r5 
r6 
1  K
1  K
k s1  K gly  C gly  K OH   COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
k s 2  K gly  C gly  K OH   COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
k s 3  K1, 2 PDO  C1, 2 PDO  K OH   COH 
1  K
1  K
1  K
1  K
 C1, 2 PDO 
2
1, 2  PDO
k s 4  K gly  C gly  K OH   COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
k s 5  K gly  C gly  K OH   COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
k s 5  K EG  C EG  K OH   COH 
 C gly  K EG  C EG   1  K OH   COH  
2
gly
Table S2-8. Parameter estimation for Model v
Model v
Constants
ks1
ks2×101
ks3×10-1
ks4
ks5
ks6
Kgly×10-1
KOH-×10-2
K1,2-PDO
KEG×10-3
130oC
145oC
160oC
25.2±1.74
1.15±0.09
5.52±1.30
1.37±0.17
<0
8.59
1.55
1.40
8.30±7.07
1.08
4.12±2.47
0.23±0.14
7.03
0.27±0.17
0.51±0.31
0.03±0.04
0.77
47.8±18.2
0.01±0.005
4122±8719
-
14
Table S2-9. Rate equations for Model vi
r1 
r2 
r3 
1  K
1  K
k s1  K gly  C gly  COH 
 C gly   1  K OH   C OH  
2
gly
k s 2  K gly  C gly  COH 
 C gly   1  K OH   COH  
2
gly
k s 3  K1, 2PDO  C1, 2PDO  COH 
1  K
r4 
r5 
r6 
1  K
1  K
1  K
 C1, 2PDO 
2
1, 2 PDO
k s 4  K gly  C gly  COH 
 C gly   1  K OH   COH  
2
gly
k s 5  K gly  C gly  COH 
 C gly   1  K OH   COH  
2
gly
k s 5  K gly  C gly  COH 
 C gly   1  K OH   COH  
2
gly
Table S2-10. Parameter estimation for Model vi
Model vi
Constants
ks1
ks2×101
ks3×10-2
ks4×10-2
ks5×10-2
ks6×10-2
Kgly×10-2
KOH-×10-3
K1,2-PDO
130oC
145oC
160oC
1.28±0.10
5.86±0.51
6.47±0.01
6.52
9.45±1.63
3.41±1.63
3.80
1.00
0.37
1.98±0.16
1.08
24.9±3.60
12.9±1.48
24.1±1.57
12.1±33.1
4.16±4.49
100.6±109
0.20
-
15
3. Error analysis
Table S3-1. Repeated experiments in glycerol conversion on Pt/C catalyst
T (oC)
Time (h) Cgly
CLA
C1,2-PDO
CEG
CMeOH
CEtOH
CPrOH
COH-
130
130
130
130
145
145
145
145
160
160
160
160
1.0
1.0
4.5
4.5
1.0
1.0
4.0
4.0
0.5
0.5
4.0
4.0
0.086
0.075
0.190
0.182
0.108
0.127
0.303
0.265
0.265
0.303
0.301
0.342
0.029
0.034
0.067
0.063
0.032
0.034
0.124
0.109
0.109
0.124
0.144
0.164
0.004
0.004
0.005
0.004
0.015
0.018
0.010
0.009
0.009
0.010
0.011
0.012
0.019
0.016
0.023
0.020
0.022
0.019
0.046
0.040
0.040
0.045
0.206
0.234
0.008
0.006
0.012
0.012
0.011
0.014
0.028
0.024
0.024
0.028
0.071
0.081
0.002
0.002
0.005
0.004
0.004
0.003
0.019
0.017
0.017
0.019
0.028
0.032
1.070
1.112
1.050
0.919
0.108
0.027
0.954
0.835
0.835
0.954
0.848
0.964
0.92
1.001
0.758
0.886
0.861
0.910
0.540
0.518
0.591
0.615
0.361
0.337
(1) Experimental error
Key experiments in tandem glycerol conversion were repeated and values of substrate/product
concentration were calculated (see Table S3-1), the error of which was taken into account when
parameter estimation was carried out.
(2) Measuring error
The maximum error for HPLC analysis (repeated injection of one sample) is only < 0.08%, which is
much lower compared with experimental error (approximately 3~12%).
(3) Error analysis of reaction parameters-weighted least squares
The goal of suing weighted least squares is to ensure that each data point has an appropriate level of
influence on the final parameter estimation. However, it is difficult to evaluate the appropriate level of
16
each component (e.g. glycerol, lactic acid, etc), therefore the weight factor for each species and replicates
(repeated experimental results) were considered is 1.0 during estimation of reaction parameters.
(4) Error analysis in calculation of activation energy
The activation energy was estimated based on reaction rate constants at each temperature. The
uncertainty of activation energy for tandem glycerol conversion is summarized in Table 1-12. The
equation for activation energy is k=ko×e(-Ea/RT).
Table S3-2. Error analysis for activation energy in tandem glycerol conversion
T (oC)
Error in Ea (kJ/mol)
130
145
160
Ea
ln(ko)
(kJ/mol)
ks1×100
1.33±0.09
1.97±0.15
4.09±0.59
53.0
23.82
0.958
0.42
0.76
0.30
0.49
ks2×10-1
6.09±0.51
10.8±0.50
22.8±3.04
63.7
26.24
0.991
0.53
5.38
1.57
1.88
ks3×10-2
6.48±0.98
24.8±3.38
55.6±14.0
104.2
36.19
0.985
5.57
13.22
5.07
7.14
ks4×10-2
5.95±0.53
12.9±1.48
39.3±4.23
104.2
35.81
0.967
1.55
13.30
4.47
5.25
ks5×10-2
7.00±1.87
24.2±1.64
131.6±
9.01
141.6
47.25
0.988
1.37
0.93
2.21
3.14
ks6×10-1
1.12±0.48
2.85±0.39
9.32±2.02
102.3
36.04
0.992
1.64
4.71
1.88
2.84
Kgly×10-2
3.83±0.47
3.75±0.25
3.50±0.48
4.3
3.21
0.902
-0.04
0.19
0.09
0.15
KOH-×10-3
2.21±0.17
1.81±0.22
1.33±0.29
24.5
-5.65
0.980
-0.32
0.77
0.28
0.41
K1,2-PDO×10-1
3.72±0.08
2.02±0.45
1.01±0.48
63.0
-12.01
0.997
1.80
6.82
2.40
3.19
KEG×10-2
4.00±0.37
2.50±0.48
1.13±0.12
60.9
-15.89
0.972
1.25
0.51
0.55
0.86
ki
R2
err
err
(130) (145)
err
(160)
err
The unit for error is kJ/mol
Error analysis in activation energy (example)
(a) Functions for error propagation are listed in Table 1-13, which will be used to calculate the error
(uncertainty) of activation energy.
17
Table 3-3. Functions for propagation of error
Function
Propagated error
𝑧 =𝑎+𝑏
∆𝑧 = [(∆𝑎)2 + (∆𝑏)2 ]1/2
𝑧 =𝑎×𝑏
∆𝑧
∆𝑎 2
∆𝑏 2
= [( ) + ( ) ]
𝑧
𝑎
𝑏
𝑧 = 𝑙𝑛𝑎
∆𝑧 =
1/2
∆𝑎
𝑎
∆𝑎 is the uncertainty of 𝑎.
(b) The uncertainty for activation energy is determined by the following equation:
ln(𝑘 𝑇 ) = ln(𝑘𝑜 ) −
𝐸𝑎⁄
𝑅𝑇
After rearrangement,
𝐸𝑎 = 𝑅𝑇[ln(𝑘𝑜 ) − ln(𝑘 𝑇 )]
Therefore, the uncertainty for activation energy,
2 1/2
∆𝐸𝑎
∆𝑅𝑇 2
∆[ln(𝑘𝑜 ) − ln(𝑘 𝑇 )]
= [(
) +(
) ]
[ln(𝑘𝑜 ) − ln(𝑘 𝑇 )]
𝐸𝑎
𝑅𝑇
2 1/2
∆𝐸𝑎
∆𝑇 2
∆[ln(𝑘𝑜 )] + ∆ [ln(𝑘 𝑇 )]
= [( ) + (
) ]
[ln(𝑘𝑜 ) − ln(𝑘 𝑇 )]
𝐸𝑎
𝑇
1/2
∆𝐸𝑎
∆𝑇 2
(∆𝑘𝑜 )/𝑘𝑜 + (∆𝑘 𝑇 )/𝑘 𝑇 2
= [( ) + (
) ]
[ln(𝑘𝑜 ) − ln(𝑘 𝑇 )]
𝐸𝑎
𝑇
To calculate the average error for 𝐸𝑎 based on different temperature,
18
2
2 1/2
2
∆𝐸𝑎 = [(∆𝐸𝑎 𝑇1 ) + (∆𝐸𝑎 𝑇2 ) + (∆𝐸𝑎 𝑇2 ) ]
(c) Take ks3 at 160 oC (433 K) for example.
2 1/2
∆𝐸𝑎 𝑇1
(∆𝑘𝑜 )/𝑘𝑜 + (∆𝑘 𝑇1 )/𝑘𝑇1
∆𝑇 2
= 𝐸𝑎 [( ) + (
) ]
𝑇1
[ln(𝑘𝑜 ) − ln(𝑘 𝑇1 )]
1
13.9
0.9932 ) +
= 98.9
1
2 2
(1 −
𝑘𝐽
1𝐾 2
49.9
× (
) +(
= 20.9 𝑘𝐽/𝑚𝑜𝑙
)
[34.58 − ln(49.9 × 10−2 )]
𝑚𝑜𝑙
433 𝐾
[
]
(d) Similarly, error at 130 oC and 145 oC is 1.11 kJ/mol and 2.44 kJ/mol respectively.
(e) The average error for activation energy is calculated based on the following equation:
∆𝐸𝑎 𝑇1 + ∆𝐸𝑎 𝑇2 + ∆𝐸𝑎 𝑇3 2
∆𝐸𝑎 2
(
) =[
]
(3 × 𝐸𝑎 )
𝐸𝑎
∆𝐸𝑎 =
∆𝐸𝑎 𝑇1 + ∆𝐸𝑎 𝑇2 + ∆𝐸𝑎 𝑇3 1.11 + 2.44 + 20.9
=
= 8.16 𝑘𝐽/𝑚𝑜𝑙
3
3
4. Sensitivity analysis
(1) False compensation
If reaction rates are measured over only a fairly small range of temperature and the activation energy is
determined based on the reaction rate constants derived from Arrhenius plot, the value determined may
be subject to considerable error. In other words, the sensitivity of obtained activation energy to
temperature may be much more significant compared with the maximum error from reaction constants.
Therefore, it is necessary to analyze the sensitivity of activation energy derived from kinetic modeling.
19
The sensitivity of activation energy is calculated based on the temperature range and error of reaction
constants within the investigated temperature. The general equation is
𝛿𝐸𝑎 =
2 × 𝑅 × 𝑇1 × 𝑇2
× 𝑒𝑟𝑟𝑚𝑎𝑥 %
|𝑇1 − 𝑇2 |
Where 𝛿𝐸𝑎 is maximum error (sensitivity) of activation energy (kJ/mol), 𝑅 is the gas constant (kJ/mol.K),
𝑇1 and 𝑇2 are investigated temperature (K) and 𝑒𝑟𝑟𝑚𝑎𝑥 % is the maximum error in reaction constants
(determined from 95% confidence level from Table S3-2).
(2) Sensitivity of activation energy
Table S4-1. Sensitivity of activation energy in tandem glycerol conversion
relative error at T (oC)
ki
130
ks1
ks2
ks3
ks4
ks5
ks6
Kgly
KOHK1,2-PDO
KEG
0.07
0.08
0.15
0.09
0.27
0.43
0.12
0.08
0.02
0.09
145
160
0.08
0.14
0.05
0.13
0.14
0.25
0.11
0.11
0.07
0.09
0.14
0.22
0.04
0.14
0.12
0.26
0.22
0.48
0.19
0.11
Maximum error
𝛿𝐸𝑎
(kJ/mol)
14.0
12.9
24.4
11.1
25.8
41.5
13.3
25.3
46.0
18.6
For example, the maximum error for ks1 is 0.14 in tandem glycerol conversion (see Table 1-12), while
the temperature difference is 433 K (160 oC)-403 K (130 oC) = 30 K. Therefore the sensitivity of Ea for
ks1 is
𝛿𝐸𝑎 =
2 × 8.314 × 433 × 403
× 0.14 = 14.0 𝑘𝐽/𝑚𝑜𝑙
1000 × 30
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Evaluation of external and internal mass transfer limitation
Intraparticle transfer limitation of glycerol:
d  m  1   p  R initial 
  p 

6  2  D e  w cat  C gly 
0.5
d p  0.0001m
 p  2.3  103 kg / m 3
R initial  0.52kmol / m 3 .h (maximum reaction rate at 160 oC)
D e  9.4  10 -9 cm 2 / s  0.34m 2 / h (data at 25 oC)
w cat  9.9kg / m 3 (maximum catalyst loading)
C gly  1.1kmol / m 3
  0.000299
Even if the error of parameter is 10000%, the significance intraparticle mass transfer limitation (0.0299)
is still much lower than 0.2.
Effect of stirring rate:
(See Table 2 for experimental conditions, reaction time 2 h)
At 100 RPM: glycerol conversion is 3.6% (indicating negligible conversion during startup).
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At 500 RPM: glycerol conversion is 42.1%.
At 800 RPM: glycerol conversion is 44.9%.
22