This document summarizes a study on dehydrogenation of methylcyclohexane (MCH) over 3 wt% Pt/V2O5 and 3 wt% Pt/Y2O3 catalysts for hydrogen delivery applications. The catalytic activity was tested using a spray-pulse mode reactor, which creates alternating wet and dry conditions on the catalyst surface. 3 wt% Pt/Y2O3 achieved a hydrogen evolution rate of 958 mmol/g/min at 350°C and nearly 100% hydrogen selectivity. 3 wt% Pt/V2O5 achieved 98% MCH conversion at 60 minutes using the spray-pulse reactor. The catalysts were characterized using techniques such as XRD, CO-chemisorption

1. Dehydrogenation of methylcyclohexane over Pt/V2O5
and Pt/Y2O3 for hydrogen delivery applications
Anshu Shukla, Jayshri V. Pande, Rajesh B. Biniwale*
National Environmental Engineering Research Institute (NEERI), Council of Scientific and Industrial Research, Nehru Marg,
Nagpur, Maharashtra 440020, India
a r t i c l e i n f o
Article history:
Received 26 August 2011
Received in revised form
12 November 2011
Accepted 15 November 2011
Available online 16 December 2011
Keywords:
Hydrogen delivery
Methylcyclohexane
Dehydrogenation catalysts
Spray-pulse reactor
Metal oxide support
a b s t r a c t
Dehydrogenation of methylcyclohexane (MCH) for hydrogen transportation and delivery
application was carried out over 3 wt% Pt/V2O5 and 3 wt% Pt/Y2O3 catalyst. The catalytic
activity was tested using a spray-pulse mode of reactor. Effective dehydrogenation of MCH
under spray-pulse mode of reactant injection was observed. In terms of hydrogen evolu-
tion rate at 60 min from start of reaction the activity of 958 mmol/g/min was obtained at
temperature of 350
C. Nearly 100% selectivity toward hydrogen was obtained. A relatively
high conversion of 98% was observed with 3 wt% Pt/Y2O3 at 60 min using an advanced
spray-pulse reactor system. The catalysts were characterized using x-ray diffraction
pattern (XRD), CO-chemisorption metal analysis, scanning electron microscopy (SEM) and
X-ray photoelectron spectroscopy (XPS) analysis.
Copyright ª 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights
reserved.
1. Introduction
Use of cycloalkanes such as cyclohexane, methylcyclohexane
(MCH), decalin, etc. has been reported for efficient hydrogen
storage and transportation [1]. A reaction pair of hydrogena-
tion of aromatics at hydrogen production facility to produce
cycloalkanes and subsequent dehydrogenation of cyclo-
alkanes at fueling station would help in delivering hydrogen to
fuel cell vehicles [2]. Having relatively higher hydrogen storage
capacity of 6e8 % wt and 60e63 kg/m3
in terms of weight and
volume basis is an advantage with cycloalkanes. Besides
a high storage capacity, the reaction of dehydrogenation is
very selective toward hydrogen and aromatics (condensable)
over Pt containing catalysts. The hydrogen delivered using
this method therefore is free from any contaminants
including CO or CO2 [2]. Among the cycloalkanes MCH was
considered as a potential candidate in this study due to two
major reasons. The first was that the dehydrogenated product
of MCH is toluene which is safer in health impact point of view
as compared to benzene a product of cyclohexane dehydro-
genation. The second reason was MCH has relatively higher
capacity of hydrogen storage.
While using Pt as a catalyst for dehydrogenation reactions
a few important aspects need to be considered for the cata-
lyst’s design [3,4]. These include oxidation state of Pt, its
interaction with support and with second metal in case of
bimetallic catalyst [2]. The interaction with support or other
metal is due to hydrogen spillover, reverse spillover or surface
migration [2]. Literature reports metal oxides and perovskites
can be good option for several catalytic reactions [5]. Exploring
the role of support we have earlier reported the dehydroge-
nation of MCH over Pt supported on various metal-oxides
namely, La2O3, Al2O3, CeO2, MnO2, TiO2, Fe2O3 and ZrO2 [3].
Use of metal oxides as support promotes the activity and
* Corresponding author. Tel.: þ91 712 2249885x410, þ91 9822745768 (mobile); fax: þ91 712 2249900.
E-mail address: rb_biniwale@neeri.res.in (R.B. Biniwale).
Available online at www.sciencedirect.com
journal homepage: www.elsevier.com/locate/he
i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 7 ( 2 0 1 2 ) 3 3 5 0 e3 3 5 7
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doi:10.1016/j.ijhydene.2011.11.078

2. selectivity through strong metal support interaction. It has
been reported that hydrogen spillover phenomenon has been
observed in materials such as MoO3 and WO3 [6]. The observed
hydrogen spillover in metal oxides is attributed to the favor-
able thermodynamics and the small energy barriers of H-
migration from catalyst to the substrate and the subsequent
proton diffusion in bulk lattice derived from the massive H-
bonding network intrinsic to these materials. A mechanism
that invokes high proton mobility cannot account for spillover
in carbon based materials because a similar H-bonding envi-
ronment does not exist [6].
The unsteady-state conditions for maintaining a high
temperature of the catalyst’s surface would favor the endo-
thermic reaction of dehydrogenation [7]. Accordingly use of
super-heated film [8] and spray-pulsed reactors [2] have been
reported for creating unsteady-state reaction conditions on
the surface of the catalysts. In this heterogeneous system
wherein a liquid reactant such as MCH is used and the catalyst
is solid the contact between reactant and catalysts is rather
difficult. If the MCH is fed to the reactor in liquid phase in
a packed bed reactor, the catalyst surface temperature is
limited to the boiling point of the reactant under liquid pool
conditions. If the evaporation of reactant occurs and reaches
to the catalyst’s bed in vapor phase, the contact of the reactant
molecule with catalyst surface is limited by the diffusion
through a boundary-layer between the catalysts and gas
phase [7]. Creating alternate wet and dry conditions on the
surface of the catalyst using spray-pulsed injection of the
reactant is reported as a solution for the same [9]. When the
reactant is fed in the form of a pulse of atomized spray over
heated catalysts for a short period generally in the range of
1e10 ms then the reactant gets in contact with surface of the
catalysts and evaporates on the surface. The evaporation of
the reactant on the catalyst’s surface produces a dense vapor
phase in the vicinity to catalyst. A next pulse of reactant is
injected after a definite interval by controlling the injection
frequency in the range of 0.3e1 Hz. This interval before the
arrival of next pulse provide time for complete reaction and
removal of reactant/product from the surface of the catalysts.
The phenomena can be considered as creating alternate wet-
dry conditions on the surface of the catalysts. The wet
condition referred herein is with respect to dense vapor phase
formed near to catalysts surface.
It is well reported that vanadium(v) in V2O5 on exposing to
hydrogen at 400
C reduces to lower oxidation state [10]. V2O5
is an acidic oxide wherein vanadium ions are present in dis-
torted octahedrons. They become oxygen deficient on reduc-
tion with hydrogen and carbon monoxide. Thus, this
phenomenon enhances the removal of oxygen and increases
the hydrogen evolution [10]. Y2O3 is an active catalyst for
dehydrogenation reactions. Considering these aspects, V2O5
and Y2O3 were chosen as supports for Pt catalysts in this
study. We report herewith enhanced hydrogen evolution rates
during dehydrogenation of MCH over Pt/Y2O3 and Pt/V2O5. The
Fig. 1 e Details of experimental setup including a spray-pulsed reactor equipped with injection nozzle, plate type heater,
frequency controller and product separation by condenser.
i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 7 ( 2 0 1 2 ) 3 3 5 0 e3 3 5 7 3351

3. catalysts were characterized using XRD, CO-chemisorption
analysis, SEM and XPS technique.
2. Materials and methods
2.1. Catalysts synthesis and characterization
Commercial V2O5 and Y2O3 obtained from MERCK with 99.95%
purity were used as supports for Pt catalysts. Wet impregnation
method was used for platinum loading. Platinum chloride
solution (HIMEDIA, India) was used as precursor of Pt. The
powder diffraction analysis was carried out using XRD instru-
ment of Rigaku-make, (Model MiniflexII-DD34863) operated at
30 kV and 15 mA with a monochromator and using Cu-Ka
radiation (k ¼ 0.15418 nm). The sample was scanned for 2q
ranges from 5 to 60
. Specific surface area measurement was
done by Quantachrome Autosorb e 1C automated gas adsorp-
tion system. Around 20e30 mg of samples was degassed at
200
C for 10 h in vacuum of 1 Â 10À5
torr and N2 adsorption was
measured at liquid nitrogen temperature of 77 K. Adsorption
isotherms for N2 were measured at this temperature where
BrunauereEmmetteTeller (BET) surface area was measured in
relative pressure range of 0.05 P0 1. The results of BET
surface area were obtained by five point adsorption method.
2.2. Catalytic reactions
In order to improve the catalytic activity a spray-pulse reactor
was employed. Experimental setup for spray-pulse reactor is
depicted in Fig. 1. A glass reactor equipped with plate type
heater was used for the reactions. Catalysts, about 0.3 g each,
were kept on the surface of the plate heater which was posi-
tioned perpendicular to the vertical axis of the reactor. The
Fig. 2 e XRD patterns for (a) 3 wt% Pt/V2O5 and (b) 3 wt% Pt/
Y2O3 catalysts.
Fig. 3 e SEM patterns for (a) and (b) 3 wt% Pt/Y2O3, (c) and (d) 3 wt% Pt/V2O5.
i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 7 ( 2 0 1 2 ) 3 3 5 0 e3 3 5 73352

4. pretreatment of catalyst’s surface was performed using
nitrogen flow at 300
C with flow rate of 20 ml/min Nitrogen
was purged during reaction to maintain an inert atmosphere.
The catalyst activation was performed in the flow of hydrogen
with the flow rate of 30 ml/min All the reactions were per-
formed at an atmospheric pressure. The reaction temperature
was maintained at 350
C. Activity of catalyst was studied by
spray-pulse mode of reactant feed. The reactant was fed
through a fine nozzle fitted at the top of reactor. The injection
frequency and pulse width was controlled by operating nozzle
with a frequency generator. The reactant was fed with the
pulse frequency of 0.3 Hz and pulse width of 10 ms. A
condenser was attached at the outlet of reactor for separation
of product. The gaseous product was continuously examined
by a TCD-GC (SHIMADZU, porapak-Q, 10 m). The condensed
hydrocarbon products were analyzed at the end of the reac-
tion using a FID-GC. The hydrogen evolution rate was calcu-
lated by observing hydrogen concentration in product gas
with respect to time. The % yield and % conversion were
calculated using equations (1) and (2):
% yield of H2 ¼
moles of H2 formed
moles of MCH reacted
(1)
% conversion of MCH ¼
moles of MCH reacted
moles of MCH fed
(2)
3. Results and discussion
3.1. Catalysts characterization
The specific surface area of V2O5 was found to be 6.7 m2
/g. The
X-ray diffraction pattern of 3 wt% Pt/V2O5 as shown in Fig. 2 (a)
confirmed the well crystalline nature of V2O5. XRD patterns
were matched with JCPDS card no. 76-1803 which confirmed
the V2O5 phase. The platinum presence could not be identified
due to relatively lower loading of catalyst over the support.
This can also be attributed to well disperse catalysts over the
support. The dispersion of platinum over the support was
estimated using CO-chemisorption analysis. From metal
surface analysis the dispersion of catalyst was obtained to be
21.5%. The specific surface area of commercial Y2O3 was
estimated ca. 6.37 m2
/g. The crystalline nature of Y2O3 was
confirmed using JCPDS card no. 89-5591 as shown in Fig. 2(b).
The metal dispersion was observed as 31.5%. Although the
surface area values for both the oxides and Pt nominal loading
were in the same range the dispersion of metal estimated by
CO-chemisorption were considerable different with a higher
dispersion in case of Y2O3 as support. This could be due to
either variation in reduction of the Pt over the metal oxides
during activation step before CO-chemisorption or reduction
of some amount of metal oxide under hydrogen atmosphere
conditions and contributing toward metal surface area in
addition to the Pt sites.
The dispersion of Pt over Y2O3 and V2O5 was substantiated
by examination of morphology of reduced Pt/Y2O3 and Pt/V2O5
(reduced under H2 flow rate at 400
C) using SEM. From Fig. 3
(a) and (c), it can be observed that grain size of Pt is smaller
on the surface of Y2O3 than the surface of V2O5. It can also be
observed that the dispersion is more prominent with Y2O3
than V2O5.
3.2. Variation in pulse frequency for dehydrogenation of
MCH
Fig. 4 shows hydrogen evolution rates observed during dehy-
drogenation of MCH with pulse frequency variation for feed.
The pulse width was kept constant as 10 ms. The pulse
frequency was set to 1, 0.33 and 0.2 Hz (with injection intervals
of 1, 3 and 5 s respectively). The hydrogen evolution was ob-
tained as 577, 30 and 5.83 mmol/gmet/min at 6 min respectively
for the set pulse injection frequencies. Among these conditions
0
100
200
300
400
500
600
0 20 40 60 80
Time (min)
H2evolution(mmol/gmet/min)
Pulse Frequency 1 Hz,
Pulse width 10 ms
Pulse Frequency 0.5 Hz,
Pulse width 10 ms
Pulse Frequency 0.3 Hz,
Pulse width 10 ms
Fig. 4 e Hydrogen evolution rates with variation in pulse
width and pulse injection frequency of methylcyclohexane
over 3 wt% Pt/V2O5, the catalysts used was 0.3 g and the
reaction temperature was 350
C.
Fig. 5 e Hydrogen evolution rates for 3 wt% Pt/Y2O3 and
3 wt% Pt/V2O5 at 350
C during dehydrogenation of
methylcyclohexane using spray-pulsed reactor.
i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 7 ( 2 0 1 2 ) 3 3 5 0 e3 3 5 7 3353

5. the highest hydrogen evolution was obtained at 1 Hz pulse
injection frequency, however with the time the activity was
found to be declining to hydrogen evolution rate of 15 mmol/
gmet/min at 90 min. The hydrogen evolution rate with 0.33 Hz
pulse frequency was found to have a linear rise and hydrogen
evolution rate 90 min was obtained as 228.3 mmol/gmet/min.
Hydrogen evolution rate obtained with 0.2 Hz pulse frequency
was 39.8 mmol/gmet/min at 90 min. Therefore, an optimized
pulse frequency was considered to be 0.33 Hz in combination
with pulse width of 10 ms.
The variation in the hydrogen evolution rates at different
feed conditions can be well explained by considering the
amount of liquid reactant received on the catalysts surface
under given conditions. In case of pulse injection frequency of
1.0 Hz the amount of MCH delivered was 0.68 mmol/min. This
was 2 and 3 times higher as compared to the amount delivered
at pulse injection frequency of 0.5 and 0.3 Hz respectively.
Although the pulse width was kept constant at 10 ms the
condition on the surface of the catalyst’s varied with varying
pulse injection frequency.
At higher feed injection frequency of reactant, catalyst’s
surface was enriched with MCH and thus initially results into
a high hydrogen evolution rate. A continuous introduction of
reactant on the surface of the catalyst’s lowers temperature
and this reduces the hydrogen evolution rates. At an opti-
mized feed condition of pulse injection frequency of 0.3 Hz
and pulse width of the catalyst’s activity was rather stable and
was higher than pulse injection frequency of 0.5 Hz. There
could have been possibilities of manipulating the pulse
injection width. However, experience and reported literature
suggest using the higher pulse width. The equipment used in
these experiments was limited to maximum pulse width of
10 ms.
3.3. Role of support: dehydrogenation of MCH over 3 wt
% Pt/Y2O3 and 3 wt% Pt/V2O5
MCH was well dehydrogenated over 3 wt% Pt/Y2O3 and 3 wt%
Pt/V2O5 under optimized reaction conditions mentioned
above. Fig. 5 show hydrogen evolution rate with respect to
time for dehydrogenation of MCH over 3 wt% Pt/V2O5 and 3 wt
% Pt/Y2O3. The hydrogen evolution of 958 mmol/gmet/min and
772 mmol/gmet/min was observed at 60 min and 90 min for
3 wt% Pt/Y2O3. The MCH conversion was obtained as 95.90%
and 68.56%. The hydrogen evolution rate with 3 wt% Pt/V2O5
catalyst at 60 min and 90 min was obtained as 137.35 mmol/
gmet/min and 228.33 mmol/gmet/min respectively. The MCH
conversion for 3 wt% Pt/V2O5 was calculated as 20.3% and
32.06% at 60 min and 90 min respectively.
The hydrogen evolution rate was also observed upto
150 min for both the catalysts. Hydrogen evolution rate of
703 mmol/gmet/min was observed at 114 min which was stable
25000
30000
35000
40000
45000
50000
150 153 156 159 162 165 168
B.E. (eV)
Intensity(a.u.)
Y 3d5/2
40000
45000
50000
55000
60000
65000
525 530 535 540
B.E. (eV)
Intensity(a.u.)
O 1s
162000
163000
164000
165000
166000
167000
168000
169000
68 70 72 74 76 78 80
B.E. (eV)
Intensity(a.u.)
Pt
0 PtO
0 200 400 600 800 1000
B.E. (eV)
Intensity(a.u.)
fresh catalyst
used catalyst
a b
dc
Fig. 6 e XPS spectrum for 3 wt% Pt/Y2O3, (a) Overall spectra for fresh and used catalyst, (b) spectra for Y2O3 in fresh catalyst,
(c) spectra for oxygen in fresh catalyst, (d) spectra for Pt0
and PtO in fresh catalyst.
i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 7 ( 2 0 1 2 ) 3 3 5 0 e3 3 5 73354

6. upto 150 min. With 3 wt% Pt/V2O5 the hydrogen evolution was
in the range of 240e270 mmol/gmet/min from 78 to 102 min
after that it remained stable in the range from 320 to 335
mmol/gmet/min from 120 to 150 min.
Difference in hydrogen evolution rate with the use of
different supports for the platinum can be explained by the
catalyst surface characterization. The CO-chemisorption
results reveal better Pt dispersion over the Y2O3 i.e. about
31.5% than V2O5 i.e. 21.5%. Enhanced selectivity and conver-
sion with 3 wt% Pt/Y2O3 can be attributed to high dispersion
catalyst over the support. Further, the activity of Pt depends
on the interaction with support and resulting oxidation state.
An overall XPS spectra for fresh and used 3 wt% Pt/Y2O3
catalyst is depicted in Fig. 6(a). Whereas Fig. 6(b) shows the
oxidation state for Y2O3 for 3 wt% Pt/Y2O3 catalyst which was
reduced in hydrogen flow under set temperature cycle. The
peak at B.E. of 158.6 eV confirms the presence of Y3d5/2 bands
of Y2O3 [11]. Fig. 6 (c) shows the peak of oxygen in the sample.
It is well reported that peak obtained at approximately
531.5 eV is designated to formation of OH group at the surface
as reported in literature. This can be attributed to the forma-
tion of YeOH group at the surface [12]. The peaks for Pt can be
seen at B.E. of 71.04 eV and 74 eV as shown in Fig. 6 (d). This
confirms the presence of Pt0
(Pt metal) and some amount of
PtO (Pt oxide) on the surface of Y2O3 [13].
After dehydrogenation of MCH over 3 wt% Pt/Y2O3, the
oxidation state for the catalysts were tested. The peak for
Y3d5/2 was obtained at the position of B.E. 158.6 eV thus
resembling its stable oxidation state of Y2O3. Fig. 7 (a) shows O
1s peaks which are deconvulated into two doublets. The peaks
were deconvulated using Gaussian function. The peaks were
obtained at position of 529 eV and 531.7 eV. The peak obtained
at 529 eV can be assigned to Y2O3 according to literature [14].
Also, the peak at 531.7 eV can be assigned to the formation of
YeOH group, which is reported by Gougousi and coworkers
[15]. The PtO was formed over the support and this was also
confirmed with peak at 74 eV Fig. 7 (b) shows high-resolution
background corrected peak for C1s, which shows a peak at
285 eV and tail at 289 eV. The peak at 289 eV may include
contribution of C¼O, as referred in the literature [16]. The ratio
of Pt0
to PtO was ca. 10.3 and 1.1 for fresh and used catalysts
respectively. Thus, lowering of hydrogen evolution rate after
50000
55000
60000
65000
70000
75000
525 527 529 531 533 535
B.E. (eV)
Intensity(a.u.)
Y-OH
Y2O3
36000
38000
40000
42000
44000
279 284 289
B.E. (eV)
Intensity(a.u.)
C 1s
C=O
a
b
Fig. 7 e XPS spectrum for used 3 wt% Pt/Y2O3 catalyst, (a)
spectra for oxygen (O 1s), (b) spectra for carbon (C 1s).
20000
25000
30000
35000
40000
500 510 520 530
B.E. (eV)
V2p3/2
V2p1/2
0 200 400 600 800 1000
B.E. (eV)
Intensity(a.u.)
Intensity(a.u.)
fresh catalyst
used catalyst
a
b
Fig. 8 e XPS spectrum for fresh 3 wt% Pt/V2O5, (a) overall
spectra for fresh and used catalyst, (b) spectra for V2O5.
i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 7 ( 2 0 1 2 ) 3 3 5 0 e3 3 5 7 3355

7. 100 min can be attributed to combined effect of oxidation of
Pt0
to PtO and formation of carbon on the catalysts surface. In
this case formation of PtO may be the prevailing reason for the
loss of activity of the catalyst.
Lower MCH conversion was obtained using 3 wt% Pt/V2O5 i.e.
about ca. 32e33%. No profound effect was obtained in terms of
change in hydrogen evolution rate with the time. The difference
in catalytic activity can be attributed to oxidation state of cata-
lyst before and after the reaction. The catalyst was exposed to
hydrogen using defined temperature cycle and was then tested
for XPS spectrum. Fig. 8 (a) shows an overall spectrum for 3 wt%
Pt/V2O5 catalyst. Fig. 8 (b) explains the XPS spectrum for V2p1/2
andV2p3/2 bands for V2O5. A sharp peakofoxygen(O1s) level was
observed at approximately 530 eV, resembling lattice oxygen of
V2O5 as mentioned in the literature [17]. The peaks for Pt was
observed at 71.2 eV and 74.5 eV, which can be well attributed to
the presence of Pt0
and some amount of PtO at the surface. The
ratio of Pt0
to PtO was ca. 1.7 and 1.5 for fresh and used catalysts
respectively. Formation of PtO even in case of fresh Pt/V2O5
catalyst may be the reason for relatively lower activity. Further,
there was no significant change observed for Pt0
and PtO ratio in
the fresh and used catalysts.
The catalytic activity exhibited by 3 wt% Pt/Y2O3 is excel-
lent when compared to the reported data as listed in Table 1.
The activity is higher than the reported activity for a contin-
uous system.
3.4. Kinetics of reaction
The rate of reaction was calculated by differential equation as
mentioned in Ref. [3]. The dehydrogenation of MCH at 350
C
using spray-pulse reactor with 3 wt% Pt/V2O5 was observed to
be first order reaction with rate constant to be 3.37 per min.
The order of reaction for 3 wt% Pt/Y2O3 is calculated to be first
order with rate constant to be 0.0028 per min.
4. Conclusions
Efficient catalysts based on Pt/Y2O3 and Pt/V2O5 has been re-
ported for their activity toward dehydrogenation of MCH. Role
of metal support interaction has been discussed for different
behavior of these catalysts with respect to activity and
stability. Advantages of using spray-pulsed reactor have been
delineated through a comparative data on dehydrogenation
reaction. A catalyst, 3 wt% Pt/Y2O3 exhibits excellent activity
of ca. 958 mmol/gmet/min of hydrogen evolution rate under
continuous reactor system using spray-pulse reactor.
Acknowledgment
Financial support received from Ministry of New and Renew-
able Energy, New Delhi is acknowledged. The authors Ms.
Anshu Shukla and Ms. Jayshri Pande would like to acknowl-
edge CSIR for their Senior Research fellowship. We also thank
to Indian Institute of Chemical Technology (IICT), Hyderabad
and National Chemical Laboratory (NCL), Pune for CO-
chemisorption analysis and X-ray photoelectron spectros-
copy (XPS) techniques respectively.
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C) H2 Evolution
(mmol/gmet/min)
Ref.
1 3.82 wt % Pt/AC Batch-wise 300 1700 [1]
3 0.1 wt% K þ 0.6 wt% Pt/Al2O3 Fixed-Bed 320 744 [18]
4 3 wt% Pt/Al2O3 Spray-pulse Reactor 350 7.6 [3]
5 3 wt% Pt/V2O5 Spray-pulse Reactor 350 330 This study
6 3wt% Pt/Y2O3 Spray-pulse Reactor 350 966 This study
Spray-pulse Reactor (pulse frequency 0.3 Hz, 10 ms width).
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