Y.-z. Xiang et al. / Journal of Molecular Catalysis A: Chemical 351 (2011) 70–75
75
and the Pd clusters, in which the shortest distance between oxy-
gen and Pd is 2.81 A. On Pd7/ACs, although the benzene ring of
Acknowledgements
˚
␣-phenylethanol is bonded with Pd cluster, the hydroxyl-group in
␣-phenylethanol is close to the interface of Pd clusters and ACs
support, in which the distance between oxygen in hydroxyl and
This work was supported by National Natural Science Founda-
tion of China (NSFC-20976164, NSFC-20906081 and 21176221),
Zhejiang Provincial Natural Science Foundation of China (ZJNSF-
R4110345) and National Basic Research Program of China (973
Program) (2011CB710803).
˚
Pd is 2.38 A. Therefore, the hydrogenation of acetophenone on the
Pd/ACs catalyst result in the hydrogenolysis of the hydroxyl-group
in ␣-phenylethanol molecular, which will result in the forma-
tion of by-product ethylbenzene. While, the hydrogenolysis of the
hydroxyl-group in ␣-phenylethanol molecular could be inhibited
because the hydroxyl-group in ␣-phenylethanol is far away from
the interface of the Pd particle and CNTs support when ␣-phenyl
ethanol was adsorbed on the Pd/CNTs catalyst. These could be
the reason for the significantly difference in the ␣-phenyl ethanol
selectivity over the two catalyst.
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