Controlling Hydrodeoxygenation of Stearic Acid to n-Heptadecane and n-Octadecane by Adjusting the Chemical Properties of Ni/SiO2–ZrO2 Catalyst

Article abstract of DOI:10.1002/cctc.201601162

A series of SiO₂–ZrO₂ mixed oxides with varying SiO₂ concentrations were hydrothermally synthesized and used as support for Ni in the hydrodeoxygenation of stearic acid. ZrO₂ provides a relatively low surface area and only Lewis acid sites, and Ni supported on ZrO₂ produces n-heptadecane from stearic acid through hydrogenation and decarbonylation. The SiO₂–ZrO₂ mixed oxides have a higher specific surface area than ZrO₂ as well as an unprecedented spherical and nanolayered morphology. Br?nsted acid sites were created by the incorporation of SiO₂ into ZrO₂, promoting the hydrodeoxygenation activity of Ni and specifically opening a new reaction route to n-octadecane through the dehydration of 1-octadecanol intermediate into 1-octadecene with subsequent hydrogenation.

Full text of DOI:10.1002/cctc.201601162

Accepted Article
Title: Controlling hydrodeoxygenation of stearic acid to n-heptadecane
and n-octadecane via chemical properties of Ni/SiO2-ZrO2
Authors: Sebastian Foraita, Yue Liu, Gary Haller, Eszter Barath, Chen
Zhao, and Johannes Lercher
This manuscript has been accepted after peer review and appears as an
Accepted Article online prior to editing, proofing, and formal publication
of the final Version of Record (VoR). This work is currently citable by
using the Digital Object Identifier (DOI) given below. The VoR will be
published online in Early View as soon as possible and may be different
to this Accepted Article as a result of editing. Readers should obtain
the VoR from the journal website shown below when it is published
to ensure accuracy of information. The authors are responsible for the
content of this Accepted Article.
To be cited as: ChemCatChem 10.1002/cctc.201601162
Link to VoR: http://dx.doi.org/10.1002/cctc.201601162
A Journal of
www.chemcatchem.org

10.1002/cctc.201601162
ChemCatChem
FULL PAPER
Controlling hydrodeoxygenation of stearic acid to n-heptadecane
and n-octadecane via chemical properties of Ni/SiO2-ZrO2
Sebastian Foraita,[a] Yue Liu,[a] Gary L. Haller,[a] Eszter Baráth,*[a] Chen Zhao,†[a] and Johannes A.
Lercher*[a],[b]
Abstract: A series of SiO2-ZrO2 mixed oxide with varying SiO2
concentrations was hydrothermally synthesized and used as support
for Ni in the hydrodeoxygenation of stearic acid. ZrO2 provides a
relatively low surface area and only Lewis acid sites, and Ni
supported on ZrO2 produces n-heptadecane from stearic acid via
hydrogenation and decarbonylation. The SiO2-ZrO2 mixed oxides
have a higher specific surface area as well as a novel spherical and
nano-layer shaped morphology. Brønsted acid sites are created by
incorporation of SiO2 into ZrO2 promoting the hydrodeoxygenation
activity of Ni and specifically opening a new reaction route to
n-octadecane via the dehydration of 1-octadecanol intermediate into
1-octadecene with subsequent hydrogenation.
starts with fast hydrogenolysis into propane and fatty acids
followed by slower hydrodeoxygenation of the fatty acids into
alkanes.[6a] The conversion of fatty acids, e.g., stearic acid, on
Ni/ZrO2 occurs via two pathways, one catalyzed solely by Ni and
one catalyzed synergistically by Ni and the ZrO2 support, both
leading to an alkane with one carbon less than the fatty acid, i.e.,
n-heptadecane (C17) from stearic acid (C18). On Ni, the fatty acid
is hydrogenated to the aldehyde, followed by decarbonylation of
the aldehyde to an alkane. On ZrO2, α-H abstraction and
elimination of H2O from the fatty acid adsorbed on the oxygen
vacancies leads to a ketene intermediate, which is further
hydrogenated to an aldehyde that decarbonylates to an alkane
on Ni.[7]
Generally, ZrO2 is an excellent catalytic support, inter alia due to
its high hydrothermal stability.[8] The relatively low specific
surface area poses some drawbacks, as the sites involved in the
hydrodeoxygenation pathway on ZrO2 contribute markedly to the
overall conversion. The incorporation of SiO2 has been reported
to enhance the specific surface area of ZrO2 [9] through formation
of a mixed oxide phase, and can additionally induce Brønsted
acid sites.[10] It has been shown previously that the presence of
Brønsted acid sites in proximity to Ni in zeolites enhances the
hydrogenation activity.[11]
Therefore, we explored the general applicability of the concept
of rate enhancement by introducing Brønsted acid sites via SiO2-
ZrO2 mixed oxides on the support for Ni with respect to the
hydrodeoxygenation of stearic acid, one of the most abundant
fatty acids from algae oil. It was hypothesized that the
combination of the large pore Brønsted acid support with Ni as
hydrogenation catalyst function may lead to high activity and
high selectivity retaining all carbon atoms in the fatty acid.
Introduction
The high growth rates and oil content, as well as the
independence from arable land make microalgae the ideal basis
for third-generation biofuels.[1] The conversion of algae oil into
hydrocarbon transportation fuel requires removing of oxygen
from triglycerides. This can be achieved using commercially
available sulfide catalysts, e.g., NiMoS/Al2O3, and existing
hydrotreating infrastructure.[2] However, the sulfide catalysts are
not ideal for the conversion of the nearly sulfur-free triglycerides,
because they deactivate via sulfur elimination and contaminate
the product stream with organic sulfides.[3]
Supported noble metal Ru, Pd and Pt catalysts overcome such
disadvantages offering high activity and selectivity for
hydrodeoxygenation of triglycerides and fatty acids, but are
rather expensive.[4] A more economic alternative would be
tungsten carbide based catalysts however, their performance
has not been able to reach the performance of commercial
hydrotreating catalysts (NiMo/Al2O3).[5]
Results and Discussion
We have developed two types of novel sulfur-free Ni based
catalysts to directly convert microalgae oil to diesel-range
hydrocarbons at 260 °C and 40 bar H2.[6] The catalytic process
The catalytic properties of two types of Ni catalysts, prepared by
wet impregnation on hydrothermally synthesized and
impregnated SiO2-ZrO2 supports are investigated. For details of
the preparation procedure please see experimental part.
[a]
S. Foraita, Dr. Y. Liu, Prof. Dr. G. L. Haller, Dr. E. Baráth, Dr. C.
Zhao, Prof. Dr. J. A. Lercher
Department of Chemistry and Catalysis Research Center
Technische Universität München
Catalyst characterization
Lichtenbergstraβe 4, 85747 Garching (Germany)
E-mail: johannes.lercher@ch.tum.de, eszter.barath@tum.de
Prof. Dr. J. A. Lercher
The X-ray powder diffractogram (XRD) of the ZrO2 samples,
prepared by the hydrothermal synthesis (H), are presented in
Figure 1. The diffractogram of unmodified monoclinic ZrO2
(m-ZrO2) with its characteristic diffraction pattern is shown as
well for comparison. It shows the expected diffraction peaks at
24.5, 28.3, 31.6 and 34.5° with a shoulder at 35.3° (JCPDS card
[b]
Institute for Integrated Catalysis
Pacific Northwest National Laboratory
902 Battelle Boulevard, Richland, WA 99352 (USA)
Current address: Shanghai Key Laboratory of Green Chemistry and
Chemical Processes, Department of Chemistry, East China Normal
University, North Zhongshan Rd 3663, Shanghai 200062 (China)
†
Supporting information for this article is given via a link at the end of
the document
This article is protected by copyright. All rights reserved.

10.1002/cctc.201601162
ChemCatChem
FULL PAPER
No. 37-1484).[12] With increasing SiO2-content, the peak intensity
(6 SiO2-ZrO2 (H)) decreased, suggesting lower crystallinity. In
parallel, the crystal phase of ZrO2 changed from monoclinic to a
29 SiO2-ZrO2
(002)m
(111)m
(111)m
(200)m
new phase (27 SiO2-ZrO2 and 37 SiO2-ZrO2 (H)), which has
been assigned to tetragonal ZrO2 in literature
[12c,
12d]. Above
16 SiO2-ZrO2
4 SiO2-ZrO2
40 wt% SiO2, only broad signals characteristic for amorphous
oxides[13] were observed, while diffraction peaks of either
monoclinic or tetragonal ZrO2 were absent, implying an
amorphous structure of the resulting materials[14]. In line with that,
the peak attributed to pure SiO2 was lowered in intensity.
Presumably, this is the result of atomic dispersion in mixed SiO2-
ZrO2 where Zr-O units are alternating with SiO4-tetrahedra. In
contrast, the diffraction patterns remain identical when the ZrO2
is modified by impregnation with SiO2, indicating the crystal
structure of ZrO2 is not affected by SiO2 (Figure 2).
m-ZrO2
20
25
30
35
40
2 Theta [ ]
Figure 2. XRD patterns of ZrO2 modified with increasing amount of SiO2 by
impregnation method (0 – 29 mol%).
A)
High Resolution Scanning Electron Microscopy (HR-SEM)
37 SiO2-ZrO2
(111)t
The highly increased specific surface area of the materials
prepared by the hydrothermal method is also manifested in the
HR-SEM micrographs. While unmodified ZrO2 (Figure 3, upper
left) showed particles with several micrometers in diameter, the
surface of ZrO2-SiO2 is more facetted, forming nano-layers with
increasing content of SiO2. For 37 SiO2-ZrO2, highly organized
structures with a primary particle size of 1 µm are formed. Nano
(002)t
(200)t
27 SiO2-ZrO2
6 SiO2-ZrO2
(111)
m (111)m
(002)m
(200)m
m-ZrO2
layers arrange in
a way that spheres with sponge like
15
20
25
30
35
40
morphologies are formed. Similar structures were reported by
Faria et al.[15] The 67 ZrO2-SiO2 had an extraordinary
morphology, in which the excess SiO2 not incorporated into ZrO2
was deposited on the surface of the lamellar structure as SiO2-
nanoparticles with a size of 10 nm (Figure 3, bottom right). In
contrast, the SiO2 impregnated ZrO2 samples did not show such
a change in morphology and were comparable in shape to the
reference material independent of the degree of the SiO2 loading
(Figure 4). The silica deposits are visible on the ZrO2 surface.
2 Theta [ °]
B)
SiO2
67 SiO2-ZrO2
61 SiO2-ZrO2
49 SiO2-ZrO2
15
20
25
30
35
40
2 Theta [ °]
Figure 1. XRD patterns of ZrO2 modified with increasing concentrations of
SiO2 by the hydrothermal method. A) 0 - 37 mol% SiO2. B) 49 - 100 mol%
SiO2.
This article is protected by copyright. All rights reserved.

10.1002/cctc.201601162
ChemCatChem
FULL PAPER
Figure 4. HR-SEM images of untreated ZrO2 (0 mol% SiO2) and ZrO2
impregnated with SiO2 at increasing loadings.
Physicochemical properties
As shown in Table 1, with the increase of SiO2 concentration,
the BET surface areas of the Ni/SiO2-ZrO2, determined by N2
physisorption, increased from 72 m2∙g-1 for Ni/m-ZrO2 to
193 m2∙g-1 for Ni/37 SiO2-ZrO2, significantly higher than reported
before,[16] while it afterwards decreased to 67 m2∙g-1 for
Ni/67 SiO2-ZrO2, which is close to the value for Ni/SiO2. The high
BET surface area for Ni/37 SiO2-ZrO2 (193 m2∙g-1) is due to the
small crystal size, which was only 2.5 nm compared to 7.1 nm of
m-ZrO2 (Table S1). In contrast, the catalysts prepared by the
SiO2-impregnation method only had specific surface areas
between 71 – 97 m2∙g-1 (Table 2).
Figure 3. High resolution scanning electron microscopy (HR-SEM) images of
untreated ZrO2 (0 mol% SiO2), 6 SiO2-ZrO2, 27 SiO2-ZrO2, 37 SiO2-ZrO2,
67 SiO2-ZrO2 prepared by one-pot hydrothermal method.
Table 1. Physicochemical properties of SiO2 modified Ni/ZrO2 catalysts (one-pot hydrothermal).
wt% Ni [b]
D[c]
d[c]
Concentration of
acid sites[d]
Concentration of
basic sites [e]
Catalyst[a]
SBET
[m2∙g-1]
[%]
[%]
[nm]
[mmol∙g-1]
[mmol∙g-1]
Ni/ZrO2
72
122
128
193
141
111
67
9.7
9.4
9.8
10
2.9
2.5
1.8
1.7
1.9
2.1
2.5
3.8
35
41
57
61
52
49
40
27
0.15
0.23
0.34
0.28
0.24
0.19
0.11
0
0.30
0.25
0.23
0.12
0.10
0.09
0.06
0
Ni/6 SiO2-ZrO2
Ni/27 SiO2-ZrO2
Ni/37 SiO2-ZrO2
Ni/49 SiO2-ZrO2
Ni/61 SiO2-ZrO2
Ni/67 SiO2-ZrO2
Ni/SiO2
9.8
9.8
10
75
9.5
[a] Number in the label is mol% SiO2. [b] Determined by Ni-AAS. [c] Dispersion (D) and particle size (d) were
determined by H2-Chemisorption. [d] Determined by TPD of NH3. [e] Determined by TPD of CO2.
This article is protected by copyright. All rights reserved.

10.1002/cctc.201601162
ChemCatChem
FULL PAPER
Table 2. Physicochemical properties of SiO2 impregnated Ni/ZrO2 catalysts.
wt% Ni [b]
D[c]
d[c]
Concentration of
acid sites [d]
Concentration of
basic sites [e]
Catalyst[a]
SBET
[m2∙g-1]
[%]
[%]
[nm]
[mmol∙g-1]
[mmol∙g-1]
Ni/ZrO2
72
71
86
97
9.7
10
2.9
3.0
3.1
3.6
35
33
33
28
0.15
0.16
0.16
0.16
0.30
0.19
0.14
0.10
Ni/4 SiO2-ZrO2
Ni/16 SiO2-ZrO2
Ni/29 SiO2-ZrO2
9.7
9.9
[a] Number in the label is mol% SiO2. [b] Determined by Ni-AAS. [c] Dispersion (D) and particle size (d) were determined
by H2-Chemisorption. [d] Determined by TPD of NH3. [e] Determined by TPD of CO2.
18d, 19]
The concentration of acid sites were always lower for the Ni-
impregnated catalysts than for the parent supports (compare
Table 1 with S1 and Table 2 with S2). The acid site
concentration increased from 0.15 to 0.34 mmol∙g-1 for Ni/ZrO2
to Ni/27 SiO2-ZrO2 (H) and decreased to 0 for Ni/SiO2 (Table 1).
The concentration of acid sites for the Ni-catalysts, modified by
SiO2-impregnation was constant at 0.16 mmol∙g-1 (Table 2) and
was lower than that of the corresponding parent support
(Table S2). This indicates that the ZrO2 surface and its acid sites
are partially blocked by SiO2. With the increase of the SiO2
content, the basic site concentration for the mixed oxides
prepared with the hydrothermal method decreased from 0.25 to
0 mmol∙g-1, and that for the SiO2 impregnated samples
decreased from 0.19 to 0.10 mmol∙g-1, in line with similar studies
difference spectra.[16b,
The band at 3735 cm-1 (37 SiO2-
ZrO2 (H) and 29 SiO2-ZrO2 Imp.) is attributed to isolated SiOH
groups.[18a, 20]
LA
1448
A)
ZrO2
37 SiO2-ZrO2 (H)
29 SiO2-ZrO2 (Imp.)
SiO2
LA
1610
BA
1630
1491
1462
BA
1547
LA
1576
on SiO2-ZrO2 mixed oxides by Yamaguchi et al.[17]
.
IR spectra of adsorbed pyridine
In Figure 5 the IR spectra of adsorbed pyridine are shown for
1700
1650
1600
1550
1500
1450
1400
Wavenumber [cm-1]
unmodified monoclinic ZrO2, SiO2-ZrO2 (37 SiO2-ZrO2, H), SiO2-
impregnated ZrO2 (29 SiO2-ZrO2, Imp.) and
a pure SiO2
B)
reference. The ZrO2 showed the bands of pyridine adsorbed on
Lewis acid sites (LAS) at 1610 and 1448 cm-1 (Figure 5, A).
SiO2-ZrO2 showed emerging peaks at 1630 and 1547 cm-1
attributed to pyridinium ions formed by adsorption on Brønsted
acid sites (BAS). The band at 1462 cm-1 is attributed to pyridine
coordinately adsorbed on Lewis acid sites (LAS), the band at
1491 cm-1 to pyridine adsorbed on both strong LAS and BAS.[18]
Table 3 shows the quantification of BAS and LAS for 27 SiO2-
ZrO2 (H) and 37 SiO2-ZrO2 (H). 27 SiO2-ZrO2 (H) had the highest
total concentration of acid sites (0.93 mmol∙g-1), and 37 SiO2-
ZrO2 (H) has the highest concentration of BAS (0.36 mmol∙g-1).
In contrast, the impregnated material (29 SiO2-ZrO2, Imp.)
showed adsorption on identical sites as on ZrO2, but in lower
concentrations. This is attributed to the fact that ZrO2 is partially
covered by SiO2, leading to fewer accessible Lewis acid sites.
Finally, the pure SiO2 reference did not adsorb significant
concentrations of pyridine after evacuation at 150°C.
3735
3774
3680
3608
ZrO2
37 SiO2-ZrO2 (H)
29 SiO2-ZrO2 (Imp.)
SiO2
3800
3750
3700
3650
3600
3550
3500
Wavenumber [cm-1]
Figure 5. IR spectra of pyridine adsorbed on ZrO2 (black), 37 SiO2-ZrO2 (one-
pot hydrothermal synthesis) in orange, 29 SiO2-ZrO2 (Impregnation) in blue
and SiO2 reference (gray). A) Pyridine vibrations region (1700 – 1400 cm-1) B)
Surface Zr-OH and Si-OH stretching vibration region (3800 – 3500 cm-1).
The broad peaks at 3774 and 3680 cm-1 (Figure 5, B) are
assigned to the stretching vibrations of terminal and bridging
surface OH groups of Zr, respectively, that disappear upon
adsorption of pyridine and are visible as negative peaks in the
This article is protected by copyright. All rights reserved.

10.1002/cctc.201601162
ChemCatChem
FULL PAPER
Table 3. Concentration of Brønsted and Lewis acid sites quantified by IR
spectra of adsorbed pyridine.
LA
1448
ZrO2
A)
6 SiO2-ZrO2
27 SiO2-ZrO2
37 SiO2-ZrO2
49 SiO2-ZrO2
61 SiO2-ZrO2
67 SiO2-ZrO2
SiO2
LA
1610
Support/
modification
Total
concentration
of acid sites
Concentration
of BAS
Concentration
of LAS
BAS/
LAS
BA
1630
[µmol∙g-1]
930
[µmol∙g-1]
136
[µmol∙g-1]
794
1491
LA
1576
1462
BA
1547
Ni/27 SiO2-ZrO2
Ni/37 SiO2-ZrO2
0.17
0.95
730
356
374
1700
1650
1600
1550
1500
1450
1400
Wavenumber [cm-1]
3735
3745
B)
The IR spectra of adsorbed pyridine for all samples prepared by
the one-pot hydrothermal synthesis method with different SiO2-
contents are compared in Figure 6, A. As indicated in the
previous paragraph, the spectrum of bare ZrO2 and 6 SiO2-ZrO2
showed broad bands with low intensities at 3774 and 3680 cm-1
that are attributed to ZrOH groups (Figure 6, B). For higher
contents of SiO2 (27 – 61 mol%), bands at 3745 – 3735 cm-1
appeared that correspond to isolated SiOH groups. Like SiO2,
the mixed oxide with the highest SiO2-content (69 SiO2-ZrO2)
showed negligible adsorption of pyridine. We want to highlight
the peak at 3608 cm-1 that only appeared for 27-SiO2-ZrO2 and
37 SiO2-ZrO2, which also had the highest concentrations of BAS.
This band at 3608 cm-1 is similar in wavenumber to the bridging
OH groups in zeolites[21] responsible for the high Brønsted acid
strength. Brønsted acid sites were suggested to be present in
SiO2-ZrO2 as well (Scheme 1, A).[21c, 22] However, in a classic
substitution model this would require a sufficient number of
Zr3+-cations[23], which are unlikely to be formed under the
conditions employed.[24] Therefore, we tentatively propose a
structure (Scheme 1, B) based on Pauling’s electrostatic
valence rule.[25] The coordination number (CN) of Zr in tetragonal
ZrO2, which is the dominating phase in the presence of SiO2, is
eight, whereas the CN(Si) = 4 in SiO2. The incorporation of SiO2
into the ZrO2 structure and, thus, the formation of a mixed oxide
lead to an under-coordination of the surface oxygen for ZrO2 rich
samples. This is hypothesized to be balanced by a proton,
leading to an OH band at 3608 cm-1 accounting for the Brønsted
acid site.[26] With increasing SiO2-content, the incorporation
cannot be stabilized, resulting in phase segregation and a lower
concentration of BAS.
3774
3680
3608
ZrO2
6 SiO2-ZrO2
27 SiO2-ZrO2
37 SiO2-ZrO2
49 SiO2-ZrO2
61 SiO2-ZrO2
67 SiO2-ZrO2
SiO2
3800
3750
3700
3650
3600
3550
3500
Wavenumber [cm-1]
Figure 6. IR spectra of pyridine adsorbed on SiO2-ZrO2 (one-pot hydrothermal
synthesis) with varying mol% SiO2. A) Pyridine vibrations region (1700 –
1400 cm-1) B) Surface Zr-OH and Si-OH stretching vibration region (3800 –
3500 cm-1).
The model is derived from the considerations of Tanabe[10b]
,
taking into account the coordination numbers of both cations and
anions. According to this model, all oxygen anions are assumed
to maintain the coordination number of the major oxide
component. In contrast to that, the metal cations may retain the
coordination number of their pure metal oxides for both major
and minor component. This leads to an excess charge in a
model structure. If the excess charge is negative, it has to be
balanced by a proton generating a BAS. Accordingly, a positive
excess charge leads to the introduction of an oxygen vacancy,
and hence to a LAS. The simultaneous occurrence of BAS and
LAS, like here, may point to the existence of domains with
varying concentrations of the constituents.[27] Note that such a
model is in agreement with the Sanderson electronegativity
A) Bridging Si-O(H)-Zr
B) Terminal Zr-OH in SiO2-ZrO2
concept[28] and the mixing rule[29]
.
29Si-NMR Spectroscopy
The SiO2-modified sample (Figure 7) prepared by the one-pot
hydrothermal method (e.g. 37 SiO2-ZrO2 (H)) shows two peaks
with chemical shifts of -83 ppm and -96 ppm, that represent a 2-
fold (Q2) and 3-fold (Q3) coordination of Si-atoms as in
Si(OSi)2(OZr)2 and Si(OSi)3(OZr)1 or Si(OSi)2(OH)2 and
Si(OSi)3(OH)1, respectively.[14, 30] Si-O-H and Si-O-Zr bonds are
Scheme 1. Schematic representation of bridging OH and terminal OH group of
Si-O-Zr in mixed oxide SiO2-ZrO2.
This article is protected by copyright. All rights reserved.

10.1002/cctc.201601162
ChemCatChem
FULL PAPER
not distinguishable in 29Si-NMR.[22a] This allows us to conclude
that SiO2 and ZrO2 exist in dispersed form in a mixed oxide. In
contrast, the spectrum of the 29 SiO2-ZrO2 (Imp.) showed a
broad signal at -114 ppm corresponding to Q4, the 4-fold
coordination of siloxane bonds Si(OSi)4. This points to the fact
that the SiO2 phase and the ZrO2 phase are partially segregated.
Thus, we conclude that SiO2 forms a mixed oxide phase with
ZrO2 through a hydrothermal synthesis, whereas it is only
deposited onto the ZrO2 support by the impregnation method.
With increasing SiO2 concentration these peaks are shifted
towards lower field, due to the coordination of Si with Si
increases (Figure S1).
-114 ppm
29 SiO2-ZrO2
(LUDOX Imp.)
0.05
-83 ppm
-96 ppm
37 SiO2-ZrO2
(one-pot LUDOX)
ZrO2
-50
-60
-70
-80
-90 -100 -110 -120 -130 -140 -150
d(29Si) [ppm]
Figure 7. 29Si-MAS-NMR spectra of ZrO2, 37 SiO2-ZrO2 (one-pot
hydrothermal) and 29 SiO2-ZrO2 (Impregnation).
Hydrodeoxygenation of stearic acid
100
80
Stearic acid
C18
60
Ester
40
20
0
C17
C18-OH
0
4
8
12
16
20
24
Time of reaction [h]
Scheme 2. Proposed reaction network for the hydrodeoxygenation of stearic
acid, showing the decarbonylation route towards n-heptadecane (C17),
dehydration/hydrogenation to n-octadecane (C18) and reversible esterification
towards stearyl stearate.[6b, 7, 31]
Figure 8. Product distribution for the hydrodeoxygenation of stearic acid over
10 wt% Ni/37 SiO2-ZrO2 (H) as function of time, stearic acid (●),
a
1-octadecanol (▲), n-heptadecane (♦), n-octadecane (■) and stearyl stearate
(×). Reaction conditions: stearic acid (0.5 g), 0.05 g 10 wt% Ni/37 SiO2-ZrO2
(H), dodecane (100 mL), 260 °C, p(H2) = 40 bar, stirring at 600 rpm, 8 h.
Catalytic hydrodeoxygenation of stearic acid was carried out on
the Ni/SiO2-SiO2 catalysts. As shown in Figure 8, the initial
conversion of stearic acid on Ni/37 SiO2-ZrO2 (H) resulted in
1-octadecanol as primary product, formed by the hydrogenation
of the fatty acid (Figure 9, B).[6a] Further conversion led to the
appearance of secondary product, stearyl stearate ester,
n-heptadecane (C17) and n-octadecane (C18). Stearyl stearate
Figure 10 shows the Turnover frequency (TOF) of stearic acid
and the concentration of BAS as a function of SiO2-content for
Ni/ZrO2–SiO2 (H) catalysts. Ni/ZrO2 has a TOF of 64 (conversion
rate of 3.2 mmol∙gcat-1∙h-1). With increasing SiO2-content, the
TOF increased. The TOF of 297 (conversion rate of
8.6 mmol∙gcat-1∙h-1) for Ni/37 SiO2-ZrO2 (H) was the highest TOF
(Figure 9, A and Figure 10), decreasing with further increasing
SiO2 content (Table S3). This trend is in line with the variation of
BAS concentrations and the specific surface area of the
catalysts. The conversion rate of stearic acid on Ni follows
approximately the concentration of BAS from the SiO2-ZrO2
support (Figure 10), indicating a promotion of hydrogenation
activity of Ni by close BAS. Similar observations were made for
hydrodeoxygenation of phenolic substrates by Song et al.[11]
Because the conversion of stearic acid can be synergistically
was formed through esterification of 1-octadecanol with stearic
32]
acid.[6b,
This reaction is reversible and stearyl stearate
reached a maximum at 8 h and decayed afterwards until
depletion after 20 h. Only alkane products, n-heptadecane and
n-octadecane, remained after 24 h. n-Heptadecane was formed
via dehydrogenation of the 1-octadecanol intermediate to
1-octadecanal
with
subsequent
decarbonylation,
and
n-octadecane was formed via dehydration of 1-octadecanol to
1-octadecene with subsequent hydrogenation (Scheme 2).
This article is protected by copyright. All rights reserved.

10.1002/cctc.201601162
ChemCatChem
FULL PAPER
enhanced by ZrO2,[7] the markedly higher specific surface area
may also contribute to the activity (Figure S2). In contrast,
hydrodeoxygenation of stearic acid over SiO2-impregnated
Ni/ZrO2 catalysts showed a decrease of conversion rate with
increasing SiO2-content from 3.2 mmol∙gcat-1∙h-1 for Ni/ZrO2 to
1.4 mmol∙gcat-1∙h-1 for Ni/29 SiO2-ZrO2 (Imp.) (Figure S3, A and
Table S4). The products evolving with increasing stearic acid
conversion is similar to that on Ni/ZrO2. The decrease in activity
is attributed to the SiO2 partly covering ZrO2, reducing so the
accessible ZrO2 surface.[6a, 7]
50
A) one-pot hydrothermal
Figure 10. Turnover frequency (TOF) for the hydrodeoxygenation of stearic
acid and concentration of Brønsted acid sites as a function of SiO2-content in
the Ni/SiO2-ZrO2 catalyst prepared by the hydrothermal method. Reaction
conditions: stearic acid (0.5 g), Ni/SiO2-ZrO2 catalyst (10 wt% Ni, 0.05 g),
dodecane (100 mL), 260 °C, p(H2) = 40 bar, stirring at 600 rpm, 2 h.
40
X
30
20
10
0
It is noticeable that on Ni/ZrO2 catalyst, n-heptadecane was the
dominant hydrocarbon product at full conversion and the
n-octadecane yield was negligible,[31] while on Ni/37 SiO2-ZrO2
(H), octadecane had a yield as high as 60%. Bare ZrO2 only
possesses LAS, whereas the presence of BAS in (H) catalysts
enhanced the rate of 1-octadecanol dehydration, causing a shift
in selectivity towards n-octadecane. This shift in product
0
20
40
60
80
100
120
140
Reaction time t [min]
distribution from
n-heptadecane
to
n-octadecane
is
In
33]
advantageous from a carbon-economy point of view.[6a,
25
20
15
10
5
B) Ni/37 SiO2-ZrO2
Figure 11 the rate constants for the dehydration of
1-octadecanol leading to C18 and esterification of stearic acid
with C18-OH leading to stearyl stearate are shown. The rate
constants for both reactions have a positive correlation with the
BAS concentrations on the catalysts, indicating Brønsted acidic
proton as the active site. Obviously, the conversion of stearic
acid over Ni/37 SiO2-ZrO2 has the highest yield of n-octadecane,
because it has the highest concentration of Brønsted acid sites.
(one-pot hydrothermal)
C18-OH
Ester
Y
C17
C18
0
0
10
20
30
40
50
Conversion X [%]
Figure 9. A) Conversion of stearic acid as a function of time. B) Yields of
1-octadecanol, stearyl stearate, n-heptadecane and n-octadecane over
Ni/37 SiO2-ZrO2 (one-pot hydrothermal) as
a function of stearic acid
conversion. 1-octadecanol (▲), n-heptadecane (♦), n-octadecane (■) and
stearyl stearate (×). Reaction conditions: stearic acid (0.5 g), Ni/SiO2-ZrO2
catalyst (10 wt% Ni, 0.05 g), dodecane (100 mL), 260 °C, p(H2) = 40 bar,
stirring at 600 rpm, 2 h.
Figure 11. Rate constant for the dehydration of 1-octadecanol (■) and
esterification of stearic acid and 1-octadecanol (×) normalized to catalyst
weight as
a function of concentration of BAS on Ni/SiO2-ZrO2 catalyst.
Reaction conditions: stearic acid (0.5 g), Ni/SiO2-ZrO2 catalyst (10 wt% Ni,
0.05 g), dodecane (100 mL), 260 °C, p(H2) = 40 bar, stirring at 600 rpm, 2 h.
This article is protected by copyright. All rights reserved.

10.1002/cctc.201601162
ChemCatChem
FULL PAPER
Conclusions
Table 4. Overview of all SiO2-ZrO2 supports prepared by two
different methods.
Hydrothermal synthesis of SiO2-ZrO2 mixed oxides led to
materials with a maximum in Brønsted acid site concentration at
approximately 40 mol% of SiO2 and 60 mol% ZrO2. Brønsted
acid sites are concluded to be induced by the substitution in
oxide lattices differing in the coordination of the cations, Si4+ and
Zr4+. Differences in morphology resulted in high specific surface
areas of these mixed oxides, having a spherical morphology with
agglomerates of nano-layered materials. The higher
concentration of Brønsted acid sites and higher specific surface
area led to a maximum in the catalytic activity for stearic acid
deoxygenation for Ni/37 SiO2-ZrO2. Remarkably, an increase in
the rates of hydrogenation reactions by neighboring Brønsted
acid sites and Ni particles was observed. While the high
Brønsted acid site concentration facilitates the dehydration of
1-octadecanol intermediate, which leads to an enhanced
n-octadecane formation.
Catalyst[a]
mol%
SiO2
mol%
Si
mol%
ZrO2
mol%
Zr
ZrO2
<1
<1
100
33
6 SiO2-ZrO2 (H)
27 SiO2-ZrO2 (H)
37 SiO2-ZrO2 (H)
49 SiO2-ZrO2 (H)
61 SiO2-ZrO2 (H)
67 SiO2-ZrO2 (H)
SiO2
6
2.1
9.0
13
94
73
63
51
39
33
<1
96
83
71
31
24
21
17
13
11
<1
32
28
24
27
37
49
61
67
99
4
16
20
22
33
4 SiO2-ZrO2 (Imp.)
16 SiO2-ZrO2 (Imp.)
29 SiO2-ZrO2 (Imp.)
1.4
5.5
9.7
16
29
[a] Number in the label is mol% SiO2. (H) - one-pot hydrothermal
synthesis method; Imp. - Impregnation method
Experimental Section – Materials and Methods
For the second route, monoclinic ZrO2 was impregnated with LUDOX
TM-40 to prepare a mixed oxide enriched at the surface with SiO2. For
Chemicals:
All
chemicals
were
purchased
commercially:
[12a, 31]
this, monoclinic ZrO2 was prepared as shown previously
and
ZrO(NO3)2 × x H2O (Sigma-Aldrich, 99%), urea (Sigma-Aldrich ACS
reagent, 99.0-100.5%), LUDOX TM-40 (40 wt% SiO2-suspension, Sigma-
Aldrich), Ni(NO3)2∙6 H2O (Acros Organics, ≥98.5%), stearic acid (Sigma-
Aldrich, ≥99.5% analytical standard), 1-octadecanol (Sigma-Aldrich,
LUDOX was added dropwise onto the powdered ZrO2 with various
amounts as shown in Table S6. Subsequently, the SiO2 impregnated
ZrO2 was suspended with water, stirred for 3 h at ambient temperature
and dried overnight at 110 °C. This is called Impregnation method (Imp.).
≥99.5%
SelectophoreTM),
n-octadecane
(Sigma-Aldrich,
99%),
n-heptadecane (Sigma-Aldrich, 99%), dodecane (Sigma-Aldrich, ≥99%,
ReagentPlus).
The 10 wt% supported Ni catalysts were prepared by the wet
impregnation technique. The Ni metal precursor, Ni(NO3)2∙6 H2O (3.30 g),
was dissolved in deionized H2O, and the resultant solution was added
dropwise into 6.0 g of the powdered support with stirring in ambient air.
The slurry was further stirred for 4 h, followed by drying at 110 °C
overnight. Subsequently, the ground solid was calcined in synthetic air
(flow rate: 100 mL∙min-1) at 450 °C for 4 h (heating rate: 4 C∙min-1) and
reduced in H2 flow (flow rate: 100 mL∙min-1) at 500 °C for 4 h (heating
rate: 4 C∙min-1).
Catalyst preparation: Silica modified ZrO2 supports with various SiO2-
content were prepared by two different methods (Table 4). For the first
pathway a hydrothermal synthesis route in the presence of ZrO2 and a
SiO2 precursor was chosen. Various amount of LUDOX TM-40 (colloidal
SiO2-suspension), 44.4 g ZrO(NO3)2 • x H2O and urea were dissolved in
bi-distilled water according to Table S5 (see Supporting Information).
The solution was transferred to a stainless steel autoclave with a Teflon®
liner. Herein, at 180 °C and autogenous pressure a precipitate was
formed after 24 h. Therefore, this procedure is called one-pot
hydrothermal method (H). After washing the precipitate with H2O five
times, it was dried overnight at 110 °C and then ground and calcined in
synthetic air at 400 °C for 4 h at a heating rate of 2 C∙min-1 (flow rate:
100 mL∙min-1). The labeling of both catalysts as well as supports
corresponds to the mol% of SiO2, derived from Si elemental analysis by
ICP-OES.
Catalyst characterization
X-Ray powder diffraction (XRD) was performed on a Philips X’Pert Pro
System equipped with a Cu K radiation source (40 kV/45 mA) with 1.08°
min-1 in the 2  range of 5−70 . The crystal size of ZrO2 was determined
via Scherrer equation from full width at half maximum of the (111)
diffraction peak of ZrO2.[34]
N2-sorption. The BET surface area was determined by adsorption-
desorption with N2 at -196 °C using the Sorptomatic 1990 series
instrument. The sample was activated in vacuum at 250 °C for 2 h before
measurement. In order to measure H2-chemisorption in Thermo
Scientific’s Surfer instrument, the Ni based catalysts were reduced in H2-
flow at 450 °C for 1 h and then evacuated at 300 °C for 1 h. The H2
adsorption isotherms accounting for both chemisorption and
physisorption were measured at a pressure ranging from 9 to 400 mbar
at 25 °C. Afterwards, the system was evacuated for 20 min to remove
physisorbed H2 and to obtain chemisorbed H2 after subtraction. The
concentration of chemisorbed hydrogen on the metal was determined by
extrapolating the isotherm to zero H2 pressure. The Ni dispersion was
deduced by assuming an average surface Ni to H ratio of 1.
This article is protected by copyright. All rights reserved.

10.1002/cctc.201601162
ChemCatChem
FULL PAPER
Temperature programmed desorption (TPD) of ammonia and carbon
dioxide was carried out in a 6-fold parallel reactor system. The pressed
samples (500 - 710 µm) were first activated in He at 500 °C for 1 h and
loaded with the adsorbent NH3 or CO2 at a partial pressure of 1 mbar and
100 °C or 40 °C, respectively. The samples were then purged with He for
1 h in order to remove physisorbed species. After activation, the six
samples were heated from 100 - 770 °C with a rate of 10 C∙min-1 to
desorb NH3 and from 40 to 700 °C to remove CO2, and the signals were
detected by a Balzers QME 200 mass spectrometer.
equipped with a flame ionization detector (FID) and Agilent 5977 MS
detector, using a HP-5 capillary column (30 m, 0.32 mm inner diameter,
0.25 µm film). Reproducibility of the rates was better than ±5% for all
experiments.
Conversion = (weight of converted reactant / weight of the starting
reactant) × 100%. Yield (C%) = (C atoms in each product / C atoms in
the starting reactant) × 100%. Selectivity (C%) = (C atoms in each
product/sum of C atoms in all the products) × 100%. Turnover frequency
(TOF) is the reaction rate normalized by accessible surface Ni atoms,
which were determined by chemisorption of hydrogen or concentration of
BAS, which was determined by py-IR (where applicable). TOF = mole of
converted reactant / mole of accessible Ni on the catalyst’s surface or
mole of converted reactant / concentration of BAS. Rate of dehydration =
Atomic absorption spectroscopy (AAS) was used to determine the Ni
content of the catalysts with a UNICAM 939 AA-Spectrometer. Prior to Ni
determination, the catalysts were dissolved in boiling concentrated
sulfuric acid. Si-content of the supports was obtained by Inductively
Coupled Plasma Optical Emission Spectrometry (ICP-OES) using a
HORIBA Jobin Yvon Ultima II spectrometer. In order to prepare the
sample for measurement, the finely ground powder was digested in
Merck‘s Spectromelt A14 (Li2B4O7, LiBO2).
Δ yield of C18
/ Δ time). Rate constant of dehydration = rate of
dehydration / concentration of 1-octadecanol.
High Resolution Scanning Electron Microscopy (HR-SEM) of the
SiO2 modified supports was performed with a JOEL JSM-7500F SEM.
The finely ground samples were mounted on a multi-sample-holder by
standard preparation technique and measured with a secondary electron
ionization detector (SEI).
Acknowledgements
Financial support in the framework of AlgenFlugKraft (FKZ
LaBay74) project, supported by Bavarian Ministry of Economic
Affairs and Media, Energy and Technology (“Bayerisches
Staatsministerium für Wirtschaft und Medien, Energie und
Technologie”) and Bavarian State Ministry of Education, Science
and the Arts (“Bayerisches Staatsministerium für Bildung und
Kultus, Wissenschaft und Kunst”) is highly appreciated. We
thank Franz-Xaver Hecht for N2-sorption and H2-Chemisorption,
Martin Neukamm for AAS measurements, Tommy Hofmann,
Thomas Gronauer and Julia Tšeglakova for the catalyst
synthesis. The fruitful discussions with Dipl.-Min. Katia
Rodewald, Dr. Gabriele Raudaschl-Sieber and Dr.-Ing. Christian
A. Gärtner are highly appreciated. J.A.L. acknowledges support
for his contribution by the U.S. Department of Energy (DOE),
Office of Science, Office of Basic Energy Sciences, Division of
Chemical Sciences, Geosciences & Biosciences for exploring
alternative oxidic supports for deoxygenation reactions.
IR spectroscopy of adsorbed pyridine (py-IR) was performed on a
Thermo Fisher Nicolet 5700 IR spectrometer at a resolution of 4 cm-1 with
120 scans in the range of 1000 - 4000 cm-1 equipped with CaF2 windows.
For the adsorption measurements, the samples of ZrO2 with various
content of SiO2 were pressed into a self-supporting disc (wafer) and
mounted on the sample holder. The samples were activated under
vacuum (p = 10-6 mbar) at 450 °C for 1 h (heating ramp: 10 K∙min-1). As
soon as the sample cooled to 150 °C, a spectrum of the activated sample
was taken. Subsequently, adsorption of pyridine was performed at
0.1 mbar for 30 min until saturation/equilibration of the surface was
reached and the peak area of the IR signal remained constant. After
physisorbed pyridine was removed by evacuation (p = 10-6 mbar) at
150 °C, another spectrum was recorded. Finally, a spectrum was taken
after desorption at 450 °C for 30 min (p = 10-6 mbar). The IR spectra of
adsorbed pyridine were obtained by subtracting the spectrum of the
activated sample, and then were normalized by the weight of the sample
wafer. For quantification, the spectra were analyzed according to the
procedure described earlier, using molar integral extinction coefficients of
0.73 cm·µmol-1 (BAS) and 0.96 cm·µmol-1 (LAS).[35]
Keywords: decarbonylation • SEM • hydrodeoxygenation • IR
spectroscopy • SiO2-ZrO2 mixed oxide
Solid state 29Si MAS NMR spectroscopy measurements (29Si-NMR)
of SiO2-ZrO2 samples were obtained using a Bruker Advance 300 MHz
multinuclear FT spectrometer (B = 7.05 T) at the corresponding 29Si
resonance frequency of 59.6 MHz. The powdered samples were fully
hydrated before packing them into a 4 mm ZrO2 pencil type rotor.
Spinning at a speed of 10 kHz, 7000 – 8000 scans were recorded using
a single-pulse technique with a pulse length of 6 µs and a repetition time
of 10 s. The external standard Si[Si(CH3)3]4 with a chemical shift of
9.8 ppm for 29Si (versus TMS) was used.
[1]
[2]
G. W. Huber, S. Iborra, A. Corma, Chem. Rev. 2006, 106, 4044-4098.
J. Jakkula, V. Niemi, J. Nikkonen, V.-M. Purola, J. Myllyoja, P. Aalto, J.
Lehtonen, V. Alopaeus, Fortum Oyj, Finland; Neste Oil Oyj . 2004, p. 12
pp.
[3]
[4]
a) C. Zhao, T. Bruck, J. A. Lercher, Green Chem. 2013, 15, 1720-1739;
b) E. Furimsky, Catal. Rev. 1983, 25, 421-458.
a) M. Snåre, I. Kubičková, P. Mäki-Arvela, K. Eränen, D. Y. Murzin, Ind.
Eng. Chem. Res. 2006, 45, 5708-5715; b) M. Snåre, I. Kubičková, P.
Mäki-Arvela, D. Chichova, K. Eränen, D. Y. Murzin, Fuel 2008, 87, 933-
945; c) J. G. Immer, M. J. Kelly, H. H. Lamb, Appl. Catal. A: Gen. 2010,
375, 134-139.
Measurement of the catalytic activity
[5]
[6]
[7]
a) R. W. Gosselink, D. R. Stellwagen, J. H. Bitter, Angew. Chem. Int.
Ed. 2013, 52, 5089-5092; b) S. A. W. Hollak, R. W. Gosselink, D. S.
van Es, J. H. Bitter, ACS Catal. 2013, 3, 2837-2844.
In order to test the described catalyst systems, stearic acid (0.5 g) and
the corresponding catalyst (0.05 g) were first loaded into the autoclave
reactor (Parr, 300 mL) with dodecane (100 mL), and then purged three
times with H2. The reaction was carried out at 260 °C under 40 bar of H2
for 2 h at a stirring speed of 600 rpm. In situ samples were drawn after 20,
40, 60, 90 and 120 min, and were analyzed by Agilent 7890B GC system,
a) B. Peng, X. Yuan, C. Zhao, J. A. Lercher, J. Am. Chem. Soc. 2012,
134, 9400-9405; b) B. Peng, Y. Yao, C. Zhao, J. A. Lercher, Angew.
Chem. Int. Ed. 2012, 51, 2072-2075.
B. Peng, C. Zhao, S. Kasakov, S. Foraita, J. A. Lercher, Chem. Eur. J.
2013, 19, 4732-4741.
This article is protected by copyright. All rights reserved.

10.1002/cctc.201601162
ChemCatChem
FULL PAPER
[8]
[9]
J. Xu, A. Zheng, J. Yang, Y. Su, J. Wang, D. Zeng, M. Zhang, C. Ye, F.
[21] a) P. A. Jacobs, R. Von Ballmoos, J. Phys. Chem. 1982, 86, 3050-
3052; b) M. Boronat, A. Corma, Catal. Lett. 2015, 145, 162-172; c) H.
Knözinger, S. Huber, J. Chem. Soc. Faraday Trans. 1998, 94, 2047-
2059.
Deng, J. Phys. Chem. B 2006, 110, 10662-10671.
a) Q. Zhao, W. H. Shih, H. L. Chang, P. Andersen, Appl. Catal. A: Gen.
2004, 262, 215-221; b) J. Chandradass, K.-S. Han, D.-s. Bae, J. Mater.
Process. Technol. 2008, 206, 315-321; c) S.-G. Chen, Y.-S. Yin, D.-P.
Wang, J. Am. Ceram. Soc. 2005, 88, 1041-1045; d) S. Lecarpentier, J.
van Gestel, K. Thomas, J.-P. Gilson, M. Houalla, Appl. Catal. A: Gen.
2010, 374, 137-141.
[22] a) X. Gao, I. E. Wachs, Catal. Today 1999, 51, 233-254; b) M. Galan-
Fereres, L. J. Alemany, R. Mariscal, M. A. Banares, J. A. Anderson, J.
L. G. Fierro, Chem. Mater. 1995, 7, 1342-1348.
[23] K. A. Pokrovski, A. T. Bell, J. Catal. 2006, 244, 43-51.
[24] a) H. Hattori, M. Itoh, K. Tanabe, J. Catal. 1975, 38, 172-178; b) C.
Gionco, M. C. Paganini, E. Giamello, R. Burgess, C. Di Valentin, G.
Pacchioni, Chem. Mater. 2013, 25, 2243-2253.
[10] a) H. H. Kung, J. Solid State Chem. 1984, 52, 191-196; b) K. Tanabe, T.
Sumiyoshi, K. Shibata, T. Kiyoura, J. Kitagawa, Bull. Chem. Soc. Jpn.
1974, 47, 1064-1066.
[11] W. Song, Y. Liu, E. Baráth, C. Zhao, J. A. Lercher, Green Chem. 2015,
17, 1204-1218.
[25] T. Kataoka, J. A. Dumesic, J. Catal. 1988, 112, 66-79.
[26] Z. F. Liu, J. Tabora, R. J. Davis, J. Catal. 1994, 149, 117-126.
[27] Y. Shen, RSC Adv. 2012, 2, 5957-5960.
[12] a) W. Li, H. Huang, H. Li, W. Zhang, H. Liu, Langmuir 2008, 24, 8358-
8366; b) H. K. Schmid, J. Am. Ceram. Soc. 1987, 70, 367-376. c) F. del
Monte, W. Larsen, J. D. Mackenzie, J. Am. Ceram. Soc. 2000, 83, 628-
634. d) J.-B. Ko, S. W. Lee, D. E. Kim, Y. U. Kim, G. Li, S. G. Lee, T.-S.
Chang, D. Kim, Y. L. Joo, J. Porous Mater. 2006, 13, 325-330.
[13] C. Guimon, A. Auroux, E. Romero, A. Monzon, Appl. Catal. A: Gen.
2003, 251, 199-214.
[28] a) K. Tanabe, M. Misono, Y. Ono, H. Hattori, New Solid Acids and
Bases, Vol. 51, Kodansha and Elsevier, Tokyo and Amsterdam, 1989;
b) R. T. Sanderson, Chemical Bonds and Bond Energy, Vol. 21, 2nd
ed., Academic Press, New York, 1976; c) K. Tanabe, in Catalysis
Science and Technology, Vol. 2 (Eds.: J. R. Anderson, M. Boudart),
Springer, Berlin, 1981, pp. 231-273.
[14] R. G. Rodríguez Avendaño, J. A. de los Reyes, J. A. Montoya, T.
Viveros, J. Sol-Gel Sci. Technol. 2005, 33, 133-138.
[29] a) H. Vinek, H. Noller, M. Ebel, K. Schwarz, J. Chem. Soc. Faraday
Trans. 1 1977, 73, 734-746; b) J. A. Lercher, H. Noller, J. Catal. 1982,
77, 152-158.
[15] E. A. Faria, J. S. Marques, I. M. Dias, R. D. A. Andrade, P. A. Z. Suarez,
A. G. S. Prado, J. Braz. Chem. Soc. 2009, 20, 1732-1737.
[16] a) M. D. Rhodes, A. T. Bell, J. Catal. 2005, 233, 198-209; b) M. D.
Rhodes, K. A. Pokrovski, A. T. Bell, J. Catal. 2005, 233, 210-220.
[17] T. Yamaguchi, T. Morita, T. Salama, K. Tanabe, Catal. Lett. 1990, 4, 1-
6.
[30] a) J. A. Anderson, C. Fergusson, I. Rodríguez-Ramos, A. Guerrero-
Ruiz, J. Catal. 2000, 192, 344-354; b) Z. Wang, Y. Jiang, M. Hunger, A.
Baiker, J. Huang, ChemCatChem 2014, 6, 2970-2975.
[31] S. Foraita, J. L. Fulton, Z. A. Chase, A. Vjunov, P. Xu, E. Baráth, D. M.
Camaioni, C. Zhao, J. A. Lercher, Chem. Eur. J. 2015, 21, 2423-2434.
[32] a) T. A. Nijhuis, A. E. W. Beers, F. Kapteijn, J. A. Moulijn, Chem. Eng.
Sci. 2002, 57, 1627-1632; b) A. Corma, Chem. Rev. 1995, 95, 559-614.
[33] P. Mäki-Arvela, I. Kubickova, M. Snåre, K. Eränen, D. Y. Murzin,
Energy Fuels 2006, 21, 30-41.
[18] a) A. Jentys, N. H. Pham, H. Vinek, J. Chem. Soc., Faraday Trans.
1996, 92, 3287-3291; b) A. Travert, A. Vimont, A. Sahibed-Dine, M.
Daturi, J.-C. Lavalley, Appl. Catal. A: Gen. 2006, 307, 98-107; c) E. P.
Parry, J. Catal. 1963, 2, 371-379; d) F. Ouyang, A. Nakayama, K.
Tabada, E. Suzuki, J. Phys. Chem. B 2000, 104, 2012-2018.
[19] M. I. Zaki, M. A. Hasan, F. A. Al-Sagheer, L. Pasupulety, Colloids Surf.
A 2001, 190, 261-274.
[34] G. Xu, Y.-W. Zhang, C.-S. Liao, C.-H. Yan, Phys. Chem. Chem. Phys.
2004, 6, 5410 - 5418.
[35] S. M. Maier, A. Jentys, J. A. Lercher, J. Phys. Chem. C 2011, 115,
8005-8013.
[20] E. Gallei, D. Eisenbach, J. Catal. 1975, 37, 474-485.
This article is protected by copyright. All rights reserved.

10.1002/cctc.201601162
ChemCatChem
FULL PAPER
FULL PAPER
Sebastian Foraita, Yue Liu, Gary L.
Haller, Eszter Baráth,* Chen Zhao, and
Johannes A. Lercher*
Page No. – Page No.
Controlling hydrodeoxygenation of
stearic acid to n-heptadecane and n-
octadecane via chemical properties
of Ni/SiO2-ZrO2
Hydrothermally synthesized SiO2-ZrO2 mixed oxide has novel nano-layers
possessing Brønsted acid sites and high specific surface area. Used as supports
for Ni catalyst, they enhanced the activity for fatty acid reduction compared to
Ni/ZrO2.
This article is protected by copyright. All rights reserved.