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Published on the web December 8, 2012
Selective Hydrogenolysis of Glycerol to 1,3-Propanediol Catalyzed
by Pt NanoparticlesAlO /WO
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Tomoo Mizugaki, Takayuki Yamakawa, Racha Arundhathi, Takato Mitsudome,
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Koichiro Jitsukawa, and Kiyotomi Kaneda*
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Department of Materials Engineering Science, Graduate School of Engineering Science,
Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531
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Research Center for Solar Energy Chemistry, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531
(
Received October 3, 2012; CL-121019; E-mail: kaneda@cheng.es.osaka-u.ac.jp)
Tungsten oxide-supported platinum nanoparticles containing
aluminum oxide species (PtAlOx/WO3) act as a highly efficient
heterogeneous catalyst for the hydrogenolysis of glycerol to
by evaporation to dryness at 383 K. The obtained solid was
calcined at 773 K for 3 h in air to afford PtAlOx/WO3 (Pt 0.4
wt %, Al 0.2 wt %). XRD measurement of the PtAlOx/WO3
revealed the existence of a crystalline WO3 phase and no
diffractions due to Pt metal and aluminum oxide phases
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,3-propanediol without any additives. High 1,3-propanediol
selectivity was observed due to the concerted effect of the Pt
nanoparticles, aluminum oxide, and tungsten oxide support. The
PtAlOx/WO3 catalyst is reusable with maintaining its high
catalytic performance.
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(Figure S1). TEM and FE-SEM analyses of the PtAlOx/
WO3 showed the formation of Pt nanoparticles having an
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average diameter of 2.3 nm on the surface of WO (Figure S2).
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XPS analysis gave a surface composition of Pt and Al as the
ratio of 58:42.
Utilization of biomass feedstock has attracted much atten-
tion for reducing both the usage of non-renewable petroleum
feedstock and CO2 emission. Glycerol is an abundant biomass
derived feedstock, which is produced as a coproduct from the
The hydrogenolysis of glycerol was conducted in a Teflon
vessel placed in a stainless steel autoclave with magnetic stirring
pressurized with 3 MPa of hydrogen. In Table 1, the effect of the
additional metal species on the Pt/WO3 catalyst was inves-
tigated. The PtAlO /WO catalyst gave the highest yield of
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biodiesel synthesis and oleo industry. However, methods for
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effective utilization of glycerol to produce value-added chem-
icals have not yet been developed well. These methods are
strongly desired in both academic and industrial chemistry.
1,3-PDO (40%) with 90% conversion of glycerol (Entry 1). The
use of Mn, Zr, and Cr in place of Al resulted in moderate yields
of 1,3-PDO (2528%) (Entries 810). On the other hand,
addition of V, Re, Fe, Zn, Ga, and Mo species showed very low
yields of 1,3-PDO (Entries 1116). Preparation method of Pt
AlW catalysts strongly influenced the activity and selectivity.
AlOx/Pt/WO3 was prepared by successive loading of Pt and Al
species on WO3. On the other hand, Pt/AlOx/WO3 was obtained
by loading Al species on WO3 and then, Pt species was
impregnated. AlOx/Pt/WO3 was a poor catalyst for the hydro-
genolysis (Entry 17) and Pt/AlOx/WO3 showed moderate
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Selective transformation of glycerol as the C3 feedstock to
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value-added chemicals such as 1,3-propanediol (1,3-PDO), 1,2-
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propanediol (1,2-PDO), and cyclic carbonate, is promising.
,3-PDO is an important component of engineering plastics such
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as poly(propyleneterephthalate) (PPT). Conventionally, 1,3-
PDO is produced via a petroleum feedstock route: hydration
of acrolein or hydroformylation of ethylene oxide to 3-
hydroxypropionaldehyde followed by hydrogenation. Recently,
a biological process using fermentation of glucose has been
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activity but high selectivity for 1,3-PDO (Entry 18). Interest-
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developed, but it still suffers from low efficiency. Direct
ingly, Pt/WO itself exhibited higher catalytic activity than Pt
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hydrogenolysis of glycerol to 1,3-PDO with water as the sole
coproduct by heterogeneous catalysts is considered an ideal
process since its workup is simple. Although many catalyst
systems using Ru, Rh, Pt, IrRe, and Cu have been reported
AlOx/WO3 under similar reaction conditions but the selectivity
for 1,3-PDO was low (Entry 2 vs. 7). Without the Pt nano-
particles, neither AlO /WO nor WO showed any activity for
the hydrogenolysis reaction (Entries 19 and 20). It can be said
that the Pt nanoparticles are essential for the hydrogenolysis and
the aluminum oxide species also plays an important role in the
selective formation of 1,3-PDO.
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to date for the hydrogenolysis of glycerol to 1,3-PDO, the
selectivity for 1,3-PDO was poor, and only a few of the systems
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have successfully afforded yields of over 38%. Therefore, the
synthesis of 1,3-PDO in high yield from glycerol is challenging.
In the present study, we developed a PtAlO /WO catalyst
After the hydrogenolysis reaction, the PtAlOx/WO3 cata-
lyst was easily recovered by centrifugation and could be reused
for four consecutive cycles without appreciable loss of its
catalytic activity or selectivity (Entries 1 and 36). The amount
of Pt species leached was below the detection limit of ICP-AES
analysis (Pt: 0.04 ppm). Therefore, the hydrogenolysis reaction
proceeded on the surface of the solid PtAlOx/WO3 catalyst.
The catalytic activity of PtAlOx/WO3 was also tested in the
hydrogenolysis of 1,2-PDO and 1,3-PDO (Scheme 1). 1,2-PDO
efficiently reacted to give 1-PrOH and 2-PrOH in 76 and 9%
yields, respectively. 1,3-PDO only afforded 1-PrOH in 22%
yield, indicating that 1-PrOH is generated mainly via over-
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for the selective hydrogenolysis of glycerol to 1,3-PDO in water
without any additives. The high yield of 1,3-PDO is attributed to
the concerted effect of the Pt, AlOx, and WO3 support. The Pt
AlO /WO catalyst was reusable at least four times without any
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loss of its activity or selectivity.
The platinum-supported WO3 catalysts functionalized by
various metal salts (PtMO /WO ) were prepared by coimpreg-
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nation. Typically, 2 mL of H2[PtCl6] solution (50 ¯mol mL
and 3 mL of Al(NO3)3 solution (25 ¯mol mL ) were added to
0 mL of water, and subsequently WO powder (1 g) was added.
)
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The mixture was stirred at room temperature for 12 h, followed
hydrogenolysis of 1,2-PDO in the glycerol hydrogenolysis.
Chem. Lett. 2012, 41, 17201722
© 2012 The Chemical Society of Japan