Chemistry Reference
In-Depth Information
70
60
50
40
30
20
10
Ni-Mo
Mo
2
CWCM
2
N
WN
NbC
VC
TiN
Fig. 7 Steady-state HDO activities of carbides and nitrides compared to the commercial
sulfided NiMo/Al
2
O
3
catalyst at 370
o
C and 31 bars. Reprinted with permission from ref. 40:
S. Ramanathan, S.T. Oyama, J. Phys. Chem., 1995, 99, 16365. Copyright (1995) American
Chemical Society.
Fig. 8 Time-on-stream behavior of the MoN/GAC-NH catalysts in terms of total con-
versoin for HDO of guaiacol at 300
o
C, 3 MPa H
2
pressure, H
2
/guaiacol ratio of 2.3.
Reproduced with permission from ref. 195.
America, Inc., with SSA of ca. 1402 m
2
/g). In a study by Sepulveda et al.
71
another three commercial carbons (Pica, Norit and Cucu), with different
textural and chemical properties, were used as supports for Mo
2
N. HDO
of 2-methoxyphenol was studied in a batch reactor at 50 bars H
2
and
300 1C. The Mo
2
N/Norit, which was the one with highest fraction of
mesopores, showed the highest activity and also phenol/catechol product
ratio. It was also seen that activation with H
2
for 6 h at 400 1C, caused
increased surface nitridation, which was beneficial for activity. It was
claimed that a moderate dispersion typically was obtained (not quanti-
fied), which could be related to the surface activation of the support prior
to impregnation (sintering). The results suggested that dispersion could
be further optimized.
