J. Chen et al. / Catalysis Communications 11 (2010) 571–575
575
method was adopted for incorporating nickel species into the cat-
alyst precursor. The sol–gel led to the high dispersion of nickel spe-
cies and the strong interaction between nickel and the support,
100
8
0
which enhance the resistance of Ni
temperature. Compared with co-Ni
ventional approach, Ni P/SiO has more highly dispersed Ni
ticles. Ni P particles ranged from 3 to 7 nm in Ni P/SiO , while they
. Also, the CO uptake of
2
P to sintering at high reduction
P/SiO prepared via the con-
P par-
R-Ni-SiO
2
2
2
co-Ni P/SiO
2
2
2
2
2
Ni P/SiO
60
2
2
2
2
2
ranged from 3 to 20 nm in co-Ni
2
P/SiO
2
À1
Ni
2
P/SiO
2
was 109
P/SiO
lmol g , which is about 5 times larger than
40
that of co-Ni
2
2
. In the HDC of chlorobenzene, Ni
2
2
P/SiO cata-
lyst showed more active and stable, for which higher Ni
sion is a reason. Other factors are under investigation.
2
P disper-
20
Acknowledgements
0
0
20
40
60
80
100
The authors acknowledge the supports from the Natural Science
Foundation of Tianjin (No. 08JCYBJC01600).
Time on stream/h
Fig. 4. Performance of catalysts for hydrodechlorination of chlorobenzene.
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[
persed Ni
2 2
P/SiO catalyst was obtained via TPR process. Different
3
from the conventional approach of impregnation, the sol–gel