Environmental Engineering Reference
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OH
HO
OH
OH
OH
X : 67%
S : 47%
HO
OH
HO
OH
O
X : 93%
S : 23%
O
X : 50%
S : 61%
O
OH
OH
OH
Au/TiO
2
Au/V
2
O
5
HO
HO
OH
OH
HO
OH
O
O
X : 20%
S : 29%
X : 91%
S : 38%
OH
OH
OH
HO
OH
HO
OH
HO
OH
X : 50%
S : 21%
O
O
X : 78%
S : 30%
O
X : 72%
S : 62%
Scheme 8.6
Examples of supported gold catalyst used for glycerol oxidation reaction.
with 1 wt% Au/C. A few examples of supported gold catalysts and their
activity (Conversion: X and Selectivity: S) are shown in Scheme 8.6. From
a review of dif erent literature [151-153] it is observed that in the case of
glycerol oxidation reaction, glyceric acid formed as a main product along
with dif erent types of byproduct.
In the case of aromatic alcohol-supported gold nanoparticles catalysts,
an exceptionally high activity and selectivity towards the desired product
are shown. Some examples of alcohol conversion are shown in Figure 8.30.
Baiker
et al.
repoted that Cu-Mg-Al mixed oxide acts as an ef ective sup-
port material for gold nanoparticles, and this Au/Cu-Mg-Al catalyst was
ef ectively used for alcohol oxidation reaction [156]. Corma and cowork-
ers [157-159] showed that an Au/CeO
2
catalyst is active for
the selective
oxidation of alcohols to aldehydes and ketones
and the oxidation of alde-
hydes to acids. In their studies, the
catalysts are active at relatively mild
conditions using O
2
as an oxidizing agent. h ey also carried out the alcohol
oxidation reaction without the presence of solvent and any type of base like
NaOH. h e catalytic activity was ascribed to the Au/CeO
2
catalyst stabiliz-
ing a reactive peroxy intermediate from O
2
. Subsequently, Hutchings
et al.
[160] showed that Au-Pd alloy supported on TiO
2
enhanced the activity
for alcohols under solvent-free conditions by a factor of over 25. Recently,
Chowdhury
et al.
also showed that ceria-based mixed oxide can be used
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