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RSC Advances
the Scherrer's equation32 is 19.6 nm and 17.0 nm for 1% Pd/H-
AC and 1% Pd/M-AC catalysts, respectively, which indicates the
palladium species are in good dispersion on the 1% Pd/M-AC
catalyst.
9 E. Diaz, A. F. Mohedano, J. A. Casas, L. Calvo, M. A. Gilarranz
and J. J. Rodriguez, Comparison of activated carbon-
supported Pd and Rh catalysts for aqueous-phase
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Conclusions
The results of this work indicate that supercritical CO2 is an
excellent solvent for the catalytic hydrogenation of furfural
because it is environment friendly, cost effective, and sustain-
able. Furthermore, it has a low viscosity, which is an advantage
in a ow reactor, and the solubility of hydrogen in it is higher
than in most solvents. This shows its potential to become a very
good alternative to traditional organic solvents for such reac-
tions. On the other hand, 1% Pd/M-AC has been demonstrated
to be an efficient catalyst for the catalytic hydrogenation of
furfural in scCO2. This work should prove useful for the devel-
opment of processes for upgrading bio-oils which has a wide
range of applications.
14 P. Z. Cheng and H. S. Teng, Electrochemical responses from
surface oxides present on HNO3-treated carbons, Carbon,
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Acknowledgements
15 Z. Knez, E. Markocic, M. Leitgeb, M. Primozic, M. K. Hrncic
and M. Skerget, Industrial applications of supercritical
uids: a review, Energy, 2014, 77, 235–243.
16 H. Durak, Bio-oil production from Glycyrrhiza glabra
through supercritical uid extraction, J. Supercrit. Fluids,
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upgrading of bio-oil by HZSM-5 in sub- and super-critical
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The support of 973 Program (2013CB228104) of China is greatly
appreciated.
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