Highly active CoMo/Al (10) KIT-6 catalysts for HDS of DBT: Role of structure and aluminum heteroatom in the support matrix

Article abstract of DOI:10.1016/j.cattod.2017.04.048

Herein we report the synthesis of CoMo catalysts for the hydrodesulfurization of dibenzothiophene reaction as a function of morphological effect and heteroatom substitution on KIT-6 supports. The interconnected pores of KIT-6 seem to play a vital role in the active catalyst preparation. The activity and direct desulfurization selectivity trends of the different catalysts resulted as follows: CoMo/Al(10)-KIT-6 > CoMo/KIT-6 > CoMo/γ-Al₂O₃. The improved catalytic activity and direct desulfurization selectivity are attributed to: (I) the high surface area and interconnected pores of KIT-6 which allow large quantities of nanosized (<4 nm) active CoMoS species and (II) the aluminum deposition on the surface of KIT-6 that creates mild acidity on the support, facilitating the dispersion of these nano-sized CoMoS species. Finally, evidence of the Al incorporation into the silica Matrix is presented.

Full text of DOI:10.1016/j.cattod.2017.04.048

Catalysis Today xxx (xxxx) xxx–xxx
Contents lists available at ScienceDirect
Catalysis Today
journal homepage: www.elsevier.com/locate/cattod
Highly active CoMo/Al (10) KIT-6 catalysts for HDS of DBT: Role of
structure and aluminum heteroatom in the support matrix
C. Suresha,b, L. Pérez-Cabrera , J.N. Díaz de León , T.A. Zepeda , G. Alonso-Núñez ,
S. Fuentes Moyado
a
a
a
a
a
a,⁎
Universidad Nacional Autónoma de México, Centro de Nanociencias y Nanotecnología, Km. 107 Carretera Tijuana-Ensenada, C.P. 22800, Ensenada, B.C., Mexico
Electrodics and Electrocatalysis Division, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu, India
b
A R T I C L E I N F O
A B S T R A C T
Keywords:
Hydrodesulfurization
CoMo
Alumina
KIT-6
Herein we report the synthesis of CoMo catalysts for the hydrodesulfurization of dibenzothiophene reaction as a
function of morphological effect and heteroatom substitution on KIT-6 supports. The interconnected pores of
KIT-6 seem to play a vital role in the active catalyst preparation. The activity and direct desulfurization
selectivity trends of the different catalysts resulted as follows: CoMo/Al(10)-KIT-6 > CoMo/KIT-6 > CoMo/γ-
2 3
Al O . The improved catalytic activity and direct desulfurization selectivity are attributed to: (I) the high surface
DBT
area and interconnected pores of KIT-6 which allow large quantities of nanosized (< 4 nm) active CoMoS species
and (II) the aluminum deposition on the surface of KIT-6 that creates mild acidity on the support, facilitating the
dispersion of these nano-sized CoMoS species. Finally, evidence of the Al incorporation into the silica Matrix is
presented.
Introduction
done on the unique 3D-KIT-6 materials. Soni et al. [17] studied the
hydrotreating reaction using KIT-6 supported CoMo and NiMo catalysts
Environmental regulations are limiting the sulfur content in fuels to
low levels (< 10 ppm) for a better quality of life for all living things [1].
Hydrodesulfurization (HDS) is the most common process to reduce the
sulfur level from petroleum distillates. Nevertheless, it is hard to reach
the sulfur limits from the heavier crudes with the current catalysts and
processes. To elucidate this issue, many attempts have been taken at
various levels. Among them, the preparation of better-supported
hydrotreating catalyst is an important topic of research [2,3]. Different
supports like alumina [4,5] silica [6,7] metal oxides [8], mixed metal
oxides [9] and carbon [10], have been tested for hydrotreating
reactions. After the invention of mesoporous silica sieves, a variety of
these materials like MCM-41 [11,12], HMS [13,14], SBA-15 [15,16]
and KIT-6 [17–19] have been used as a support of catalysts for the
hydrotreating reactions. The general observation from these mesopor-
ous supported hydrotreating catalyst is the vast surface area leading to
substantial activity improvements. The nature and dimension of the
pores also play a significant role for the improved activity. The
heteroatom introduction on the surface of pure silica matrix extensively
enhances the activity of the catalyst. The deposition of aluminum,
titanium, and zirconium results in a positive improvement in the
activity of hydrotreating reactions [20].
finding a better dispersion of the active species and a faster diffusion of
reactants and products on the KIT-6 supported catalysts. In this regard,
the heteroatom effect in the KIT-6 was not yet tested as a support for
HDS of the DBT reaction. Therefore, the present study is focused on the
preparation of KIT-6 with and without aluminum and a fixed silica to
aluminum ratio was used i.e. Si/Al = 10. The resultant material was
used as a support of CoMo catalysts for the HDS of DBT; a set of catalyst
via CoMo/KIT-6 and CoMo/Al (10)-KIT-6 was prepared and tested
towards the HDS of DBT. The activity of all the catalysts was correlated
with the physicochemical properties of the support and catalysts.
Finally, the activities of the synthesized CoMo/KIT-6 catalysts were
compared with a catalyst prepared using a commercial γ-Al
2 3
O support.
2. Materials and methods
2.1. Synthesis of KIT-6 support and CoMo catalysts
The KIT-6 material was synthesized using the procedure reported
elsewhere [21]. To prepare aluminum incorporated KIT-6 (Si/Al = 10),
the parent KIT-6 was stirred for 24 h at room temperature with a
solution of aluminum isopropoxide in isopropanol. The solid products
were filtered and washed with isopropanol, dried and calcined at 500 °C
Among the different mesoporous supports, only a few studies were
⁎
Corresponding author.
E-mail address: fuentes@cnyn.unam.mx (S.F. Moyado).
http://dx.doi.org/10.1016/j.cattod.2017.04.048
Received 11 January 2017; Received in revised form 18 April 2017; Accepted 22 April 2017
0920-5861/ © 2017 Published by Elsevier B.V.
Please cite this article as: Suresh, C., Catalysis Today (2017), http://dx.doi.org/10.1016/j.cattod.2017.04.048

C. Suresh et al.
Catalysis Today xxx (xxxx) xxx–xxx
for 8 h [22]; these supports are represented as Al(10)KIT-6. All CoMo
catalysts were prepared by simultaneous wet impregnation method
using appropriate concentrations (5 wt.% Co and 14 wt.% Mo) of
acetate salts. After the impregnation, the catalysts were dried at
0.6–0.8 and an H1-type hysteresis loop confirming the orderly nature of
the mesoporous KIT-6 (Fig. 1A). As expected the capillary condensation
between the two inflections indicates the presence of uniform mesopor-
ous channels [24]. After the introduction of aluminum and impregna-
tion of the active metal compounds, the type-IV isotherm with H1-type
hysteresis loop and narrow pore size distribution are still observed
(Fig. 1B). The value corresponding to the surface area, pore volume and
pore size of KIT-6, Al (10) KIT-6 and the corresponding CoMo catalyst is
given in Table 1. A significant decrease in surface area and pore volume
100 °C for 12 h and calcined at 500 °C for 4 h.
2.2. Characterization
The low and high angle X-ray diffraction patterns were recorded
with a Philips X’Pert Diffractometer using the Cu Kα radiation
of supported CoMo catalysts was observed (Table 1). From the N
2
adsorption-desorption studies, it is concluded that the original structure
(
λ = 1.5418 Å), a nickel filter and a x’celerator as a detector. By using
the real-time multiple strip detection technique, XRD patterns were
collected in the 2θ range of 0.5–80. Surface areas of the supports and
CoMo impregnated catalysts were analyzed by Micrometrics-Tristar II.
Before the analysis, all the samples were degassed at 300 °C for 5 h
under a vacuum atmosphere. The analysis was performed at liquid
nitrogen temperature (77 K); the surface area was calculated from the
BET plot, whereas the pore size distribution was measured by the BJH
method. The coordination environments of Co and Mo in oxide catalysts
were analyzed by a Varian CARY-300 UV–vis DRS spectrophotometer
of γ-Al O and KIT-6 supports remains after the Al heteroatom
2
3
deposition and active metals loadings as well.
The mesoporous nature of pure KIT-6, Al (10) KIT-6 supports
(Fig. 2A (a, b)) and CoMo impregnated catalyst were confirmed by
low angle X-ray diffraction analysis (Fig. 2A (c, d)). The low angle XRD
patterns of calcined supports showed an intense peak at 2θ= 0.9
corresponding to the (211) plane, the hump about 1.1° is assigned to
(220) planes and the two small peaks in the 2θ range of 1.5–2 related to
(420) and (332) diffraction planes. These planes are characteristic of
the three-dimensional mesoporous KIT-6 material (Fig. A–b) [22]. Even
though a decrease in the peak intensity, the existence of all the XRD
peaks at the characteristics 2θ degrees confirms the mesoporous nature
of the base material. For Co-Mo catalysts, the mesoporous nature of
KIT-6 is retained even after the addition of almost 20 wt.% of metals
(5% wt.% Co and 14 wt.% of Mo). The wide-angle XRD analysis gave
information about the formation of different phases of Co and Mo
oxides on γ-Al O , KIT-6, and Al (10) KIT-6, which are shown in the 2θ
2
7
with a resolution of 0.24 nm. Solid state Al MAS NMR spectra was
recorded using BRUKER Switzerland, model Avance 400 MHz, spectro-
meter. The dried powdered samples were loaded into a BL4 X/Y/1H 4-
mm multinuclear probe and spun at 5 kHz according to the following
protocol: Ð/2 pulse, 7 ís; CP contact time 2 ms; 1700 scans. An internal
reference of the spectrometer was employed to calculate the chemical
shifts. High-resolution transmission electron microscopy studies were
performed using a JEOL JEM 2010 microscope (power 200 K eV). The
solids were ultrasonically dispersed in alcohol, and the suspension was
collected on carbon coated grids.
2
3
range of 5–80 (Fig. 2B). The CoMo catalyst prepared using pure KIT-6
support showed weak peaks around 2ϴ = 23.2 and 26.4 which possibly
correspond to CoMo oxides of β-CoMoO
4
phase (JCPDS-21-0868).
However, such short range peaks do not appear in the case of γ-Al O
2 3
2
.3. Hydrodesulfurization studies
and Al (10) KIT-6 supported catalyst. The absence of those peaks might
indicate that the oxide precursors of the sulfide phase are well dispersed
over the supports.
The catalytic activity was evaluated in the hydrodesulfurization
reaction of dibenzothiophene in a batch Parr reactor with a stirring rate
of 700 rpm, T = 320 °C and a total hydrogen pressure of 55 bar. Prior
To clarify the nature of the Al in the KIT-6 matrix 27Al NMR
1
3+
to the reaction, the catalyst was sulfided ex-situ with an H
2
/H
S, flow rate 60 mL min ) from 150 °C up to
00 °C (heating rate of 4 °C) and kept at this temperature for 2 h. After
purging with the inert gas to eliminate the excess of H S, the sample
2
S gas
measurements help us to elucidated the coordination sphere of Al
ions. The obtained spectra for the γ-Al and Al(10) KIT-6 are showed
in Fig. 3. The spectrum corresponding to γ-Al O revealed the multiple
−1
mixture (15 vol% H
2
2 3
O
4
2
3
2
Al environments, including the octahedral Al(6) centered at 4.9 ppm,
the pentahedral Al(5) centered at 43.5 ppm, and the tetrahedral Al(4)
centered at 65 ppm. As expected, the relative proportions of Al(4), Al(5)
and Al(6) obtained by integration of the spectra confirm that in the γ-
was transferred to the reactor under Ar atmosphere. The reactor was
charged with 0.2 g of sulfided catalyst (particle size between 80 and
1
dissolved in 100 mL of n-hexadecane. Every reaction product was
analyzed by GC in an Agilent 7890 instrument, using an Agilent 30 m
HP-5 capillary column. The initial reaction rate was obtained from the
plot of Ca (500 ppm S) versus time and normalized by the reaction
volume, and the sulfided catalyst mass used. Catalytic activity was
expressed by the initial reaction rate (mol DBT transformed per second
and gram of catalyst) [9].
00 mesh) and 100 mL of the feed composition, DBT (500 ppm of S)
2 3
Al O
around 5.6% of the Al3+ ions are in tetrahedral coordination
while 14.2% and 80.2% resulted in pentahedral and octahedral
coordination respectively. These peaks are commonly obtained for
disordered γ-Al O phase [25,26]. For the spectrum correspondent to
0
0
2
3
3+
the Al(10)KIT-6, only two environments for the Al
ions were
detected. In this case, the octahedral Al(6) was observed at
−1.7 ppm and that signal related to tetrahedral Al(4) species was
observed at 52.7 ppm. As seen, the relative quantities resulted very
differently, almost showing an inverse behavior to that seen in the γ-
3
. Results and discussion
2 3
Al O
spectrum. Only 18.8% of the Al3+ ions were detected in
3
.1. Characterization of supports and catalysts
octahedral coordination, while 81.2% resulted in tetrahedral coordina-
tion. This variation in the Al3+ ions coordination observed for the Al
(10)KIT-6 material indicated that the aluminum is preferable as a part
The textural properties of supports and catalysts were studied by N
2
adsorption–desorption analysis. The textural analysis of γ-Al
port showed an H4 hysteresis loop with a small slope in the capillary
condensation regime, indicating broad pore size distribution
Fig. 1A–a) [23] The general profile of the adsorption–desorption
isotherm for the CoMo/γ-Al catalyst resulted quite similar to that
support. This suggests that the alumina
2
O
3
sup-
2 3
of the tetrahedral silica matrix and not as isolated or segregated Al O
over the surface of the KIT-6. Also, the formation of –Si-O-Al and O-Al-
OH surface chemical environment can lead to the shift observed to
lower ppm values of the 27Al signal. These results are in line with the
reduced intensity observed in the XRD Al(10)KIT-6 pattern; both effects
confirm the incorporation of aluminum into the silica matrix.
a
(
2 3
O
2 3
obtained for the γ-Al O
textural properties resulted barely affected by the incorporation of
the metals and the subsequent thermal treatment. The isotherms of KIT-
High-resolution TEM is a valuable and informative technique to
identify the morphology of the catalytically active phase via monitoring
6
(Fig. 1A–b) and Al (10) KIT-6 (Fig. 1A–c) display a typical type IV
the MoS
2
slabs on the support matrix [27]. Fig. 4 shows selected
isotherm with two sharp inflections in the relative pressure range of
HRTEM micrographs for the different CoMo sulfided catalysts. In all of
2

C. Suresh et al.
Catalysis Today xxx (xxxx) xxx–xxx
Fig. 1. Adsorption-desorption isotherms (A, B) and pore size distribution (C, D) of a) Al
2
3
O , b) KIT‐6, C) Al (10) KIT-6 supports and d) Al
2
O
3
, e) KIT-6, f) Al (10) KIT-6 CoMo catalysts.
Table 1
Textural properties for calcined supports and CoMo catalysts.
Sample
S
BET (m2 g−1
)
Vp (cm3 g−1
)
Dp (nm)
γ-Al
KIT-6
Al(10)KIT-6
CoMo/γ-Al
CoMo/KIT-6
CoMo/Al(10)KIT-6
2
O
3
226
818
627
177
502
323
0.62
0.88
0.70
0.46
0.60
0.45
8.5
4.9
5.0
8.0
5.1
5.3
2 3
O
Fig. 3. 27Al NMR spectra for commercial γ-Al
O and Al(10)-KIT-6 samples.
2 3
Fig. 2. Low (A) and high angle (B) XRD patterns for supports and CoMo catalysts. In A: a)
KIT-6 b) Al (10) KIT-6, c) CoMo/KIT-6, d) CoMo/Al (10) KIT-6. In B CoMo catalysts
supported on a) γ-Al O , b) KIT-6, and c) Al (10) KIT-6.
2 3
and CoMo/Al(10)KIT-6 catalysts respectively. These analyses are in
agreement with observations previously reported with similar materials
[
28].
UV–vis diffuse reflectance spectroscopy was used to determine the
them, a large quantity of MoS
and stacking nature. To make quantitative comparisons, the length and
layer number of MoS slabs were measured by statistical analysis
Fig. 5). For this analysis, about 25 micrographs including a minimum
of 200 slabs were taken from different parts of each catalyst. The
catalyst prepared using Al (10) KIT-6 support displayed MoS predo-
minantly in the form of two stacked slabs with a small particle size
∼2 nm) in comparison with KIT-6 and commercial γ-Al supported
and KIT-6 supported CoMo
2
was observed varying the particle size
symmetry of Co and Mo species in the CoMo samples. The correspond-
ing electronic spectra of the calcined CoMo/KIT-6, CoMo/Al (10) KIT-6,
2
(
and CoMo/γ-Al
2 3
O oxide catalyst are shown in Fig. 6. The band
appearing around 220–270 and 300–330 nm are assigned to charge
2−
transfer transitions in isolated tetrahedral MoO
4
and octahedral
2
6+
Mo
appears around 400 nm and can be attributed to octahedral Co
species, respectively [29]. In all three catalysts, a small hump
2
+
(
2 3
O
CoMo catalyst. The commercial γ-Al
2
O
3
species [30]. T. A. Zepeda et al. [14] discussed in detail about the
various possible energy level spectra of CoMo catalyst on pure silica,
catalyst forms about the 3–4 stacking of MoS2, and the length of the
former is longer than the later. The size and stacking number of the
and Ti modified HMS supports. From these studies, the bands appearing
at 400 and 700 nm can be attributed to Co2+ and Co
3+
while the
MoS
average slab length for the samples resulted in 4.5, 4.1 and 3.6 nm for
CoMo/γ-Al , CoMo/KIT-6 and CoMo/Al(10)KIT‐6 catalysts respec-
tively. In the case of the average stacking number of the MoS resulted
as follows, 3.88, 3.75 and 3.21 slabs for CoMo/γ-Al , CoMo/KIT-6
2
are expected to reflect in the activity results of the catalysts. The
broadband appearing around 650 nm might be assigned to the presence
of tetrahedral Co2+ species [31]. However, as our XRD results
2 3
O
indicated, the possible presence of the CoMoO
4
was pointed out, this
2
2 3
O
inverse spinel could lead to the formation of octahedral Co complexes
3

C. Suresh et al.
Catalysis Today xxx (xxxx) xxx–xxx
2 3
Fig. 4. Selected HRTEM micrographs for A) CoMo/γ-Al O , B) CoMo/KIT-6 and C) CoMo/Al (10) KIT-6 catalysts.
catalysts as a function of time. The conversion profile follows the same
behavior indicating the same reaction kinetic order for all catalysts
tested. However, a significant variation was observed within the three
catalysts since the loading mass of each material in their respective
reaction was strictly the same. Taking the former into account and
when comparing only the conversion at 180 min of reaction time, the
catalyst prepared using commercial γ-Al
2 3
O as support has 40%
conversion. The KIT-6 supported catalyst showed 75% and the Al
(
(
10) KIT-6 supported catalyst displayed around 95% conversion. The Al
10) KIT-6 supported CoMo catalyst completely converted all the DBT
molecule at a period of 240 min.
Regardless the support, the reaction products observed were
biphenyl (main product), tetrahydrodibenzothiophene (traces), cyclo-
hexyl benzene (CHB) and dicyclohexyl (DCH). Many literature reports
explain the possible HDS reaction mechanism of DBT; it occurs through
two main pathways: hydrogenation (HYD) and direct desulfurization
(DDS) [32]. Fig. 7B shows the selectivity achieved at 30% DBT
Fig. 5. Statistical analysis of the HRTEM micrographs for the a) CoMo/γ-Al
2 3
O , b) CoMo/
KIT-6 and c) CoMo/Al (10) KIT-6 catalysts, A) stacking number B) slab length.
2 3
conversion for the three catalysts. The γ-Al O supported CoMo catalyst
demonstrated a selectivity of 50% throughout the DDS pathway, while
the value of DDS selectivity increased to about 80% and 90% for the
KIT-6 supported catalyst and Al (10) KIT-6 supported catalyst respec-
tively. So the trend in the DDS route of the catalyst resulted in the
following order: CoMo/Al (10) KIT-6 > CoMo/KIT-6 > CoMo/γ-
2 3
Al O . The preferential formation of biphenyl in KIT-6 and Al (10)
KIT-6 supported CoMo catalysts indicates that the DDS route was more
favorable than the HYD route.
The initial reaction rates as a function of different catalyst are
shown in Fig. 7C and two important points appear: (I) CoMo/KIT-6
2 3
catalyst show a higher activity than the commercial γ-Al O supported
catalyst, and (II) the activity of the CoMo-KIT 6 catalyst was increased
due to the aluminum heteroatom deposition. The relative order of
catalytic activity was: CoMo/Al (10) KIT-6 > CoMo/KIT-6 > CoMo/
2 3
γ-Al O . This is similar to the DDS selectivity trend indicating that more
active sites responsible for DDS reaction were created on CoMo/KIT-6
and CoMo/Al (10) KIT-6.
Fig. 6. DR-UV Vis spectroscopy study for a) CoMo/γ-Al
Al (10) KIT‐6 catalysts.
2 3
O , b) CoMo/KIT-6 and c) CoMo/
4. Conclusions
associated with d–d transitions, and therefore the broadband at 650 nm
2
+
could be rather assigned to Co ions occupying octahedral sites [30].
The shift of peaks towards a higher wavelength region (indicated by an
arrow) of the catalysts varied significantly even with the same quantity
of active metals. This implies that the support matrix impacts the
dispersion and formation of different domain sizes of the active
catalytic species. DRS-UV spectra imply that the shift of bands towards
a higher wavelength region (marked with an arrow) indicates a
formation of a large domain size of the active species.
In this work, CoMo HDS catalysts were prepared as a function of the
support and aluminum heteroatom deposition in the support matrix.
The CoMo catalyst prepared on KIT-6 support showed higher activity
than the commercial γ-Al O supported catalyst, whereas the highest
2 3
activity was observed for the catalyst prepared using the Al (10) KIT-6
as a support. The improved activity was explained in the following way:
(
I) The high surface area and interconnected pore nature of KIT-6
support may allow large quantities of active Co and Mo species in a fine
dispersion, forming nanosized (< 4 nm) active MoS species. (II) The
aluminum deposition on KIT-6 creates mild acidity on the support,
which facilitates the formation of nanosized MoS . Therefore, this study
2
3.2. Hydrodesulfurization activity
2
The activity for the ex-situ sulfided catalysts was evaluated in the
HDS reaction of DBT in a batch reactor at 320 °C under a total hydrogen
pressure of 55 bar. Fig. 7. A represents the conversion of the different
concludes that Al(10)KIT-6 support is a suitable material for supported
CoMo hydrodesulfurization catalysts with high selectivity for the DDS
pathway.
4

C. Suresh et al.
Catalysis Today xxx (xxxx) xxx–xxx
Fig. 7. Catalytic activity results for the HDS of DBT A) DBT conversion, B) % selectivity, C) Initial reaction rate for a) CoMo/γ-Al
test conditions: 500 ppm of S from DBT, 320 °C, 800 psi of H and 700 RPM.
2
2
3
O , b) CoMo/KIT-6 and c) CoMo/Al (10) KIT-6. Catalytic
[
[
[
[
14] T.A. Zepeda, T. Halachev, B. Pawelec, R. Nava, T. Klimova, G.A. Fuentes,
Acknowledgments
J.L.G. Fierro, Catal. Commun. 7 (2006) 33–41.
15] R. Huirache-Acuña, R. Nava, C.L. Peza-Ledesma, J. Lara-Romero, G. Alonso-Núñez,
B.E.M. Pawelec Rivera-Muñoz, Materials 6 (2013) 4139–4167.
16] Z.D. Huang, W. Bensch, A. Lotnyk, L. Kienle, S. Fuentes, J. Bocarando, G. Alonso,
C. Ornela, J. Mol. Catal. A: Chem. 323 (2010) 45–51.
17] K. Soni, B.S. Rana, A.K. Sinha, A. Bhaumik, M. Nandi, M. Kumar, G.M. Dhar, Appl.
Catal. B: Environ. 90 (2009) 55–63.
CONACYT supported this work under grant No. 155388, 174689,
and SENER-CONACyT1-117373, (CeMIE-Sol P28) and PAPIIT project:
IN 104714. The authors are also thankful to M. Martinez, I. Gradilla, E.
Aparicio, E. Flores and F. Ruiz for their technical support. G.A-N Thanks
to CONACyT (259931) and, DGAPA-UNAM by sabbatical support at
IRCELYON, Lyon, France.
[18] A. Duan, Ti. Li, Z. Zhao, B. Liu, X. Zhou, G. Jiang, J. Liu, Y. Wei, H. Pan, Appl. Catal.
B: Environ. 165 (2015) 763–773.
[
[
19] H. Wu, A. Duan, Z. Zhao, T. Li, R. Prins, X. Zhou, J. Catal. 317 (2014) 303–317.
20] C. Suresh, D. Santhanaraj, M. Gurulakshmi, G. Deepa, M. Selvaraj, N.R. Sasirekha,
K. Shanthi, ACS Catal. 2 (2012) 127–134.
21] F. Kleitz, S.H. Choi, R. Ryoo, Chem. Commun. 213 (2003) 6–2137.
22] G. Karthikeyan, A. Pandurangan, J. Mol. Catal. A: Chem. 361–362 (2012) 58–67.
23] D. Zhang, A. Duan, Z. Zhao, C. Xu, J. Catal. 274 (2010) 273–286.
24] T.W. Kim, F. Kleitz, B. Paul, R. Ryoo, J. Am. Chem. Soc. 127 (2005) 7601–7610.
25] J.Z. Hu, S. Xu, J.H. Kwak, M.Y. Hu, C. Wan, Z. Zhao, J. Szanyi, X. Bao, X. Han,
Y. Wang, C.H.F. Peden, J. Catal. 336 (2016) 85–93.
References
[
[
[
[
[
[1] K.G. Knudsen, B.H. Cooper, H. Topsøe, Appl. Catal. A 189 (1999) 205–215.
[2] F. Trejo, M.S. Rana, J. Ancheyta, S. Chávez, Fuel 138 (2014) 104–110.
[3] A.I. Dugulan, J.A.R. van Veen, E.J.M. Hensen, Appl. Catal. B: Environ. 142–143
(
2013) 178–186.
4] A. Ionescu, A. Allouche, J.P. Aycard, M. Rajzmann, J. Phys. Chem. B 107 (33)
2003) 8490–8497.
[
[
[
[
[
26] L.A. O’Dell, S.L.P. Savin, A.V. Chadwick, M.E. Smith, Solid State Nucl. Magn. Reson.
(
3
1 (2007) 169–173.
[
[
[
5] S. Texier, G. Berhault, G. Pérot, F. Diehl, Appl. Catal. A: Gen. 293 (2005) 105–119.
6] T.M. Stewart, Top. Catal. 13 (2000) 99–108.
7] A. Borgna, E.J.M. Hensen, L. Coulier, M.H.J.M. de Croon, J.C. Schouten, J.A.R. van
Veen, J.W. Niemantsverdriet, Catal. Lett. 90 (2003) 117–122.
27] G. Berhault, M.P. De la Rosa, A. Mehta, M.J. Yácaman, R.R. Chianelli Appl, Catal. A:
Gen. 345 (2008) 80–88.
28] A. Duana, Ti. Li, Z. Zhao, B. Liu, X. Zhou, G. Jiang, J. Liu, Y. Wei, H. Pan, Appl.
Catal. B: Environ. 165 (2015) 763–773.
29] A. Hernández, J. Escobar, J.G. Pacheco, J.A. de los Reyes, M.C. Barrera, Rev. Soc.
Quím. Méx. 48 (2004) 260–268.
30] J.E. Herrera, D.E. Resasco, J. Catal. 221 (2004) 354–364.
31] T.A. Zepeda, T. Halachev, B. Pawelec, R. Nava, T. Klimova, G.A. Fuentes,
J.L.G. Fierro, Catal. Commun. 7 (2006) 33–41.
32] A. Infantes-Molina, A. Romero-Pérez, D. Eliche-Quesada, J. Mérida-Robles,
A. Jiménez-López, E. Rodríguez-Castellón, Transition Metal Sulfide Catalysts for
Petroleum Upgrading – Hydrodesulfurization Reactions, Intech Open Science, 2017,
http://dx.doi.org/10.5772/45629 Chapter 9.
[8] Al. A. Pimerzin, P.A. Nikul’shin, A.V. Mozhaev, A.A. Pimerzin, Pet. Chem. 53 (2013)
2
45–254.
[9] J.N. Díaz de León, Appl. Catal. B: Environ. 181 (2016) 524–533.
[
[
[10] S.K. Maity, L. Flores, J. Ancheyta, H. Fukuyama, Ind. Eng. Chem. Res. 48 (2009)
1
190–1195.
[11] U.T. Turaga, C. Song, Catal. Today 86 (2003) 129–140.
[
[12] P.J. Kooyman, P. Waller, A.D. van Langeveld, C. Song, K.M. Reddy, J.A.R. van Veen,
Catal. Lett. 90 (2003) 131–135.
[13] T. Chiranjeevi, G. Muthu Kumaran, J.K. Gupta, G. Murali Dhar, Catal. Commun. 6
(2005) 101–106.
5