Page 21 - Advances in bioenergy the sustainability challenge

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0.25 < d < 0.50 mm; total flow: 350 cm /min; feed composition: 25% EtOH, 75%
p
18
H O; P = 1 atm. (Reproduced with permission from Ref . Copyright 2002, Elsevier.)
2
Figure 9.2 Ethanol conversion (X EtOH ) as a function of reaction temperature over 0.5%
Pt/Al O , 1% Pd/Al O , 2% Rh/Al O , and 5% Ru/Al O catalysts. Experimental
2 3
2 3
2 3
2 3
conditions: mass of catalyst: 0.65 g; particle diameter: 0.18 < d < 0.25 mm; TOTAL
p
3
−1
Flow: 120 cm /min; GHSV = 9350 h ; feed composition: 12.5% EtOH, 37.5% H O
2
24
(balance He); P = 1 atm. (Reproduced with permission from Ref . Copyright 2008,
Springer.)
Figure 9.3 (a) Effect of the nature of the support on the catalytic performance and (b)
selectivity toward CO over Pt (0.5 wt%) supported on the indicated commercial oxide
carriers. Experimental conditions: same as in Figure 9.2. (Reproduced in part from Ref
37 . Copyright 2012, Elsevier.)

Figure 9.4 Reaction steps for the dry reforming of methane. (a) Adsorption and
dissociation of CH and CO on the metal and the metal–support interface,
2
4
respectively. (b) CO and H desorption are fast steps. (c) Surface hydroxyls are formed
2
from hydrogen and oxygen spillover. (d) Surface oxygen species or hydroxyls oxidize
the hydrogen depleted surface methyl-like species (*CH ), forming *CH O species and
x
x
12
finally CO and H . (Reproduced from Ref . Copyright 2012, Springer.)
2
Figure 9.5 Methane conversion for transition metal catalysts supported on either silica
or alumina [reacting mixture: CH :CO :He (10:10:80); total flow rate: 100 mL/min]:
4
2
50
(a) at 723 K, TOS 45 min; (b) at 1023 K TOS 5 min. (Reproduced from Ref .
Copyright 1996, Elsevier.)

Figure 9.6 Schematic representation of the bifunctional mechanism proposed by
Takanabe for the steam reforming of acetic acid over a Pt/ZrO catalyst. (Reproduced
2
from Ref 115 . Copyright 2004, Elsevier.)

Figure 9.7 Comparison among thermodynamic data (lines) and experimental results
(symbols) of molar ratios of H (♦), CO (▪), CH (●) and CO (▲), and the conversion
2
2
4
of glycerine (▼) on 13 wt% Ni–6 wt% La O /Al O catalyst at steady state, 0.4 MPa,
2 3
2 3
different temperatures, and 1:9 glycerol/water ratio. (Reproduced from Ref 135 .
Copyright 2012, Elsevier.)
Figure 9.8 (a) H selectivity and (b) glycerol conversion at selected temperatures over
2
Al O -supported catalysts. Reaction conditions: Water/glycerol ratio = 6:1, FFR:
2 3
−1
0.5 mL/min (GHSV = 51,000 h ), data collected after 1 h of operation. (Reproduced
from Ref 139 . Copyright 2004, Elsevier.)

Chapter 10