Selective amination of 1,2-propanediol over Co/La3O4 catalyst prepared by liquid-phase reduction

Article abstract of DOI:10.1016/j.mcat.2019.110539

The catalytic coupling of alcohol and ammonia is an environmentally friendly process. Cobalt-based catalysts, modified by supports (including CeO₂, Fe₃O₄, Nb₂O₅, La₃O₄ and Al₂O₃), and prepared by the liquid-phase reduction, were used for the amination of 1,2-propanediol. The screened nano-Co/La₃O₄ catalyst exhibited an excellent catalytic performance of 68% conversion and 89% selectivity toward 2-amino-1-propanol under optimal conditions. The characterizations of the catalyst was performed by XRD, XPS, BET, TEM, TG, and CO₂-TPD, revealing a relatively large specific surface area, strongly alkaline sites and a Co-La-O transition phase, which were responsible for the selective catalysis of 1,2-propanediol. The efficient construction of cobalt-based catalysts on the basis of the active species is key to improving the efficiency of the reaction process.

Full text of DOI:10.1016/j.mcat.2019.110539

Molecular Catalysis 477 (2019) 110539
Contents lists available at ScienceDirect
Molecular Catalysis
journal homepage: www.elsevier.com/locate/mcat
Selective amination of 1,2-propanediol over Co/La O catalyst prepared by
3
4
liquid-phase reduction
⁎
Chuan-Jun Yue , Kai Di, Li-Ping Gu, Zhen-Wei Zhang, Lin-Lin Ding
School of Chemical Engineering and Material, Changzhou Institute of Technology, Changzhou 213022, PR China
A R T I C L E I N F O
A B S T R A C T
Keywords:
The catalytic coupling of alcohol and ammonia is an environmentally friendly process. Cobalt-based catalysts,
Catalytic amination
Biomass alcohol
Co-based catalyst
CeN bond construction
modified by supports (including CeO , Fe O , Nb O , La O and Al O ), and prepared by the liquid-phase re-
2
3
4
2
5
3
4
2 3
duction, were used for the amination of 1,2-propanediol. The screened nano-Co/La
excellent catalytic performance of 68% conversion and 89% selectivity toward 2-amino-1-propanol under op-
timal conditions. The characterizations of the catalyst was performed by XRD, XPS, BET, TEM, TG, and CO -TPD,
3 4
O catalyst exhibited an
2
revealing a relatively large specific surface area, strongly alkaline sites and a Co-La-O transition phase, which
were responsible for the selective catalysis of 1,2-propanediol. The efficient construction of cobalt-based cata-
lysts on the basis of the active species is key to improving the efficiency of the reaction process.
1. Introduction
alcohols. However, the improvement of the conversion and selectivity
of the reaction remains an issue [12]. Through this work, the efficient
Organic compounds containing Ce bonds are often important
construction of a catalyst is the core means of addressing this problem.
Catalyzing the amination of alcohols requires designing an effective
catalyst for matching the reaction process to the substrate. As an ex-
ample, it is known that the catalytic amination of mono alcohols pro-
ceeds through the homogeneous catalytic system represented by the
[Ir] and [Ru] complexes [13,14] and the heterogeneous catalytic
system represented by nickel- and ruthenium-based catalysts [15–17]
and bimetallic catalytic systems [18,19]. The tuning of the support or
ligand to the metal center is one of the strategies for effective catalyst
functional molecules; hence they are not only found as the structural
components of active compounds such as vitamins, hormones, alka-
loids, neurotransmitters, and natural toxicants, but are also widely used
in fine chemicals such as agrochemicals, pharmaceuticals, detergents,
dyes, food additives, and lubricants [1,2]. Among all amines, primary
amines are usually precursor molecules for the synthesis of secondary
amines, tertiary amines, and quaternary ammonium salts.
To date, there are more than ten types of synthetic methods for the
preparation of primary amines, including the nucleophilic substitution
of halogenated hydrocarbons [3], the catalytic hydrogenation of nitrile
and nitro compounds [4], the conversion of carbonyl compounds [5],
the catalytic addition of olefins [6], and the catalytic coupling of al-
cohols and ammonia [7]. From the view of green chemical, especially
when concerning non-toxic and sustainable raw materials, catalytic
coupling by the aforementioned methods are promising route for the
green synthesis of primary amines, for there are a large number of al-
cohols in the biomass, which can safely and sustainably substitute the
petrochemical feed stock in chemical industry [8]. Glycerol is a typical
biomass that has garnered widespread attention, and can be converted
to all kinds of fine chemicals, such as 1,2-propanediol, propanol, and
glycol, providing alternative materials for the chemical processes
2 3
design. For nickel-based catalysts, Ni/Al O catalyst by two preparation
methods exhibited good catalytic amination activity for secondary al-
cohols [20] and selectivity for nitrile product [21], respectively, nickel
with the highly alkaline support LaAlSiO contributed to the selective
catalytic amination of isopropanol [22], and an Al-Ce support enhanced
the catalytic activity of Ni for the amination of 1-octadecyl alcohol
[23]. These studies improved the understanding of the catalytic process
and revealed that the active center of the catalyst possessed an excellent
dehydrogenation and hydrogenation nature. On the other hand, it was
found that the catalytic amination of glycerol by Ru/C exhibited higher
activity but the poor selectivity with respect to the same reaction
conditions with polyols [24]. It is well known that there are many
primary and secondary hydroxyl groups present in biomass, and 1,2-
propanediol is suitable as a model polyol for the fundamental research
in the catalytic amination, as it contains only a primary and a secondary
[
9–11]. Theoretically, primary amines are attainable by the removal of
water from the reaction between affordable ammonia and biomass
⁎
Corresponding author.
E-mail address: ywangjung@163.com (C.-J. Yue).
https://doi.org/10.1016/j.mcat.2019.110539
Received 5 May 2019; Received in revised form 29 July 2019; Accepted 29 July 2019
2468-8231/ © 2019 Elsevier B.V. All rights reserved.

C.-J. Yue, et al.
Molecular Catalysis 477 (2019) 110539
hydroxyl group. In addition, the 2-aminpropanol product obtained from
Table 1
Effect of support on the reaction of 1,2-propanediol.
1,2-propanediol is an important intermediate for the pharmaceutical
Levofloxacin. Nevertheless related reports are few although cobalt-
based and ruthenium-based catalytic systems had an effect on the cat-
alytic amination of 1,2-propanediol [25,26], with high activity and
selectivity under the mild reaction conditions. Fortunately, cobalt-
based catalysts exhibited the potential to efficiently catalyze the ami-
nation reaction under relatively mild conditions, and the controlled
cobalt-based catalyst could also catalyze the dehydrogenation of inert
alkanes [27,28]. Thus it is necessary to prepare a highly efficient cobalt-
based catalyst to be applied for the amination of 1,2-propanediol.
The liquid reduction method is one simple and effective ways to
prepare the active components of the heterogeneous catalyst [29,30]. In
this paper, cobalt-based catalysts with different textures were prepared
by this method and used in the catalytic amination of 1,2-propanediol.
Support
Conversion/%
Selectivity/%
2A1H
1A2H
1A2A
Others
none
< 1
3.1
24.7
36.7
39.9
49.7
n.d.
n.d.
n.d.
10.8
15.3
13.5
3.0
100
18.7
5.1
10.7
4.2
CeO
Fe O
2
43.8
49.2
39.9
75.0
53.7
26.7
30.4
35.9
17.8
20.6
3
4
Nb
La
Al
2
O
5
3
O
4
2
O
3
12.7
13.0
Reaction conditions: 0.1 g catalyst with 10% Co loading, 2 mL 1,2-propanediol,
8 mL aqueous ammonia, 6 h, 160 °C. 2A1H: 2-amino-1-propanol, 1A2H:1-
Amino-2-propanol, 1A2A: 1, 2-diamino propane,others:propylene glycol ether
etc.
1
2. Experimental
2-aminopropanol by the quantitative method using isopropanol as an
internal standard.
2.1. Materials
All the reagents used were analytical grade and without further
3. Results and discussion
purification before use, and the purity of nitrogen was 99.999%.
3.1. Screening of catalytic system based on cobalt
2.2. Preparation and characterization of catalysts
The cobalt-based catalyst exhibited activity in the catalytic amina-
Catalyst preparation was based on reported procedure with slight
modification [31]. A total of 1 g of CoCl ·6H O was dissolved in a three-
2 2
necked flask with 20 mL of absolute ethanol, followed by the addition
of a certain amount of the support. A paste containing 3.5 g of NaOH
tion of 1,2-propanediol while the modification of the support to cobalt
contributed to the further improvement of the catalytic efficiency [25].
Table 1 shows that amination results of 1,2-propanediol catalyzed
by cobalt-based catalysts with different supports prepared by liquid-
phase reduction. The catalytic amination of 1,2-propanediol over cobalt
modified by lanthanum and alumina oxide showed excellent selectivity
(75.0%) to 2A1H (2-amino-1-propanol) and conversion (49.7%) while
other modified cobalt catalysts did not present better catalytic effi-
ciency. At the same time, other products like 1A2H (1-Amino-2-pro-
panol) and 1A2A (1,2-diamino propane) were formed in the catalytic
amination by supported cobalt. Obviously, the catalytic activity of
elemental cobalt was poor, revealing a relationship between catalysis
and the support material. The results of XRD analysis of the catalysts
are shown in Fig. 1(a). Cobalt modified by different supports had dif-
fering phase structures; the powdering of alumina was higher while the
crystal face of cerium oxide was relatively complete. In addition, there
were different degrees of acid or base active sites on the supports [32].
From the catalytic selectivity of the product, lanthanum oxide was
found to be a suitable alternative support.
and 3 mL of 80% N
vigorous stirring. After 20 min, 10 mL of ethanol containing 0.001 g
NaBH was added dropwise. After complete reduction, the reaction
2 4 2
H ·H O was added in a dropwise fashion with
4
system was filtered. The filter cake was completely washed with deio-
nized water and ethanol, and was transferred to vacuum chamber at
20 °C for 1 h, and finally calcined at 180 °C for 2 h under a nitrogen
atmosphere. The catalyst powder was obtained by cooling to room
temperature.
The catalysts were characterized by the undermentioned technolo-
gies. X-ray diffraction (XRD) patterns were collected on D/MAX2500 V
Rigaku, Japan) for bulk phase and structure analysis. Specific surface
area measurements (BET method) were carried out by an ASAP 2000
physical adsorption instrument (Micromeritics Instrument Corp.). The
oxidation state and surface composition were recorded using an X-ray
photoelectron spectrometry (XPS) (Kratos Ultra Axis DLD).
Transmission electron microscopy (TEM) images were acquired using a
JEOL JEM-1230 transmission electron microscope. Thermostabilities of
the samples were determined on PerkinElmer’s Pyris 1 TGA device
1
(
The molar ratio of cobalt to lanthanum in Co/La
effect on the catalytic performance. Table 2 shows the results of ami-
nation of 1,2-propanediol catalyzed by Co/La with different Co/La
3 4
O catalysts had an
3 4
O
(
Setsys 170 Thermogravimetric Analyzer, Setaram, France), the ex-
periments were carried out in N atmosphere from room temperature to
00 °C at a ramp rate of 5 °C/ min. Temperature programmed deso-
molar ratio. The variance in Co/La molar ratio did not bring obvious
changes to the catalytic efficiency, inferring that the catalytic efficiency
was closely related to the effective interfacial interaction between co-
2
5
rption (CO
Chem II 2920 apparatus. The CO
2
-TPD) measurement was carried out on Micromeritics Auto
adsorption was performed at 50 °C for
/He mixture gas(volume ratio, 10/90) at a flow
3 4
balt and La O [33]. When Co/La molar ratio increased from 0.14 to
2
0.30, the decreased amplitude of conversion only was 28.6%. The
highest conversion and selectivity to 2A1H at the Co/La molar ratio of
0.14 were 68.6 and 89.3%, respectively,with the lowest selectivity for
30 min by using CO
2
−
1
rate of 25 mL·min
.
9.4% 1A2H, less than 1% 1A2A and 1.3% other products. When Co/La
2
.3. Procedure for catalytic reaction
molar ratio was 0.06, the catalytic efficiency was low due to the support
masking the cobalt thus preventing effective interfacial contact with
1,2-propanediol. XRD showed that each catalyst had a diffraction peak
characteristic of metallic cobalt at the double diffraction angle of 44.5,
51.8 and 76.3. At the Co/La molar ratio of 0.14, the peak of the surface
pointing to the (111) crystal plane at 44.5 disappeared, and it was
presumed that it had a strong interaction with the lanthanum oxide
interface. However, other low diffraction peaks indicated that the
pulverization degree of the catalyst was relatively high. These results
helped to elucidate the structure-activity relationship of catalytic ami-
nation.
The typical procedure for the catalytic amination of alcohol was as
follows. A total of 2 mL of 1,2-propanediol, 18 mL of aqueous ammonia
and a certain amount of cobalt-based catalyst were placed in a nitrogen
atmosphere reactor. The reactor was sealed after nitrogen blowing with
a slight agitation, and then nitrogen gas was charged to 10 atm. The
reaction system was then heated for a certain period of time. After the
completion of the reaction, the catalyst was filtered and the filtrate was
analyzed with a GC or GC–MS (GCQ, Thermo Finnigan) spectrometer to
determine the conversion of 1,2-propanediol and the selectivity toward
2

C.-J. Yue, et al.
Molecular Catalysis 477 (2019) 110539
3 4
Fig. 1. XRD patterns for Cobalt-based catalysts (a) and La O support (b).
Table 2
it could be inferred that the oxygen of CoO was likely derived from the
lanthanum oxide, that is, cobalt and lanthanum oxide worked each
other in the post-processing of preparation, which was consistent with
the results revealed by XRD wherein a Co-La-O transition interface
point was identified in Cat0.
Effect of Co/La molar ration on the reaction of 1,2-propanediol amination.
Co/La (mol)
Conversion/%
Selectivity/%
2
A1H
1A2H
1A2A
Others
Fig. 3 shows the TEM image of Cat0. In general, the particles of the
catalyst were dispersed and the texture was loose. This porosity was not
only manifested as an overall accumulation, but also by the aggregated
of small particles. The degree of partial aggregation of small particles
was relatively low, due to the tendency of the two phases of cobalt and
lanthanum oxide had to disperse to form a uniform phase, while the
formation of CoO prevented the further fusion of the two phases to
some extent [33]. Since the preparation of the catalyst by the above
method did not require high temperature calcination [31]. Based on
statistical calculation, the size of the particles was about 50 nm on
average, although due to the loose aggregation the actual particle size
was below 10 nm. This was reliably the same as the particle size found
by XRD analysis, and the presence of the transient interface exhibited
the above-described catalytic amination performance.
0
0
0
0
.30
.24
.14
.06
40.0
53.9
68.6
11.2
75.0
78.2
89.3
29.1
17.9
15.3
9.4
2.9
2.1
< 1
2.2
4.2
4.4
1.3
48.4
20.3
Reaction conditions: 0.1 g catalyst, 2 mL 1,2-propanediol, 18 mL aqueous am-
monia, 6 h, 160 °C.
3
.2. Characterization of the catalyst
In order to further reveal the structure-activity relationship of cat-
alytic amination, the Co/La
balt loading was characterized by XPS, TEM, BET, CO
3
O
4
(labeled as Cat0) catalyst with 5% co-
-TPD, and TG.
2
Fig. 2 shows the XPS results for Cat0. The general image (outer
figure) indicates that the catalyst contains elements such as lanthanum,
cobalt, and oxygen, which were consistent with the element composi-
tion of the reagents used during catalyst preparation. The bond energy
analysis (internal figure) of cobalt indicates that there were two peaks
near 778 and 792 eV, that the former was attributed to the Co2p bond
energy peaks of Co, and the latter was ascribed to oxidized cobalt and
Co, respectively. From the peak area, the content of the oxidation state
of cobalt was relatively few from estimation based on split peak fitting
Fig. 4 shows the results of nitrogen adsorption and desorption of
Cat0. From the perspective of a loop, it clearly presented that the cat-
alyst had mesoporous characteristics, which were constructed by the
interaction of cobalt and lanthanum oxide, especially the (111) crystal
plane of cobalt. Macroscopically, loose particles accumulate to form
mesopores, as seen in the XRD and TEM results. As a result, a relatively
large specific surface area was obtained with BET and Langmuir surface
2
areas of 5.05 and 30.6 m /g, respectively, which were larger than the
[
34]; thus the liquid-phase reduction method used to prepare the Cat0
usual specific surface area of lanthanum oxide. The large surface area
contributed to the reactive adsorption interface of the molecules.
The surface basicity of Cat0 was characterized by CO -TPD. As
2
shown in Fig. 5, there were two types of basic sites of different strength
catalyst was sufficient to ensure that the cobalt was reduced to a simple
substance. Also, there was almost no possibility that the cobalt was
oxidized during the preparation of the nitrogen atmosphere. Therefore,
on the surface of the catalyst. As the desorption temperature rose to
580.9 and 732.6 °C, the almost equivalent peaks appeared, which cor-
responded to the medium-strength and strong basic position, respec-
tively, originating from the oxygen of the isolated hydroxyl and the
bridging oxygen on the surface of the lanthanum oxide support [32].
The presence of two types of basic sites and the intrinsic Lewis acid sites
of the lanthanum facilitated the adsorption of the substrate for cata-
lysis.
Thermogravimetric analysis of Cat0 was also performed (see sup-
plemental material), primarily reflecting the stability properties of the
catalyst. As temperature increased, only a dehydration process was
seen; no new species or phase formation or transformations were seen,
indicating that the catalyst was relatively thermostable.
Fig. 2. XPS survey spectrum (outside) and Co2p photoelectron spectra from
Co/La O (inside).
3 4
3

C.-J. Yue, et al.
Molecular Catalysis 477 (2019) 110539
Fig. 3. TEM images for Cat0.
Table 3
Effect of reaction temperature on the reaction of 1,2-propanediol amination.
T/ o
C
Conversion/%
Selectivity/%
A1H
2
1A2H
1A2A
Others
1
1
1
2
20
60
80
00
30.8
68.6
70.3
72.1
77.5
89.2
75.4
55.8
15.8
9.6
8.4
5.7
< 1
6.8
6.5
1.0
1.2
9.4
31.8
5.9
Reaction conditions: 0.1 g catalyst with 5% loading, 2 mL 1,2-propanediol,
8 mL aqueous ammonia, 6 h.
1
Table 4
2
Fig. 4. N adsorption-desorption isotherms for Cat0.
Effect of reaction time on the reaction of 1,2-propanediol amination.
t/h
Conversion/%
Selectivity/%
A1H
2
1A2H
1A2A
Others
4
6
8
50.4
68.6
75.3
78.7
56.5
89.4
80.1
75.1
37.4
9.4
10.5
8.3
5.1
< 1
7.2
< 1
1.2
2.6
5.7
1
0
10.9
Reaction conditions: 0.1 g catalyst with 5% loading, 2 mL 1,2-propanediol,
8 mL aqueous ammonia, 160 °C.
1
3.3. Catalytic performance
The efficiency of the amination of the representative polyol 1,2-
propanediol was related to reaction conditions other than the compo-
sition and texture of the catalyst with reaction temperature and time as
the main influencing parameters.
2
Fig. 5. CO -TPD profiles for Cat0.
Table 3 lists the effect of temperature on the reaction. As the reac-
tion temperature increased
from 120 to 200 ℃, the conversion increased from 30.8% to 72.1%.
4

C.-J. Yue, et al.
Molecular Catalysis 477 (2019) 110539
Fig. 6. Schematic diagram of selective amination process for 1,2-propanediol.
When the temperature was higher than 160 ℃, the selectivity toward
A1H decreased from 89.3 to 55.8%, while the 1A2H selectivity was
efficiency.
2
right decreased with the elevated temperature, because the product was
condensed with the feed stock as increased temperatures, resulting in
the consumption of the product. Compared with the reported results
Acknowledgements
The subject was sponsored by Qin Lan Project of the Education
Department of Jiangsu province in China.
[
25], the cobalt-based catalyst applied here showed a relatively high
catalytic efficiency at low temperatures. The method of catalyst pre-
paration led to the specific texture of the catalyst. The Co/La pre-
3
O
4
Appendix A. Supplementary data
pared by liquid-phase reduction method exhibited simple cobalt and a
relatively high specific area, which helped with the catalysis of surface
reactions such as dehydrogenation, condensation and hydrogenation.
The reaction time was an important parameter for evaluating cat-
alytic efficiency (Table 4). As the reaction time increased, conversion
also increased from 50.4 to 78.7% at 4 and 10 h, respectively, though
the selectivity to 2A1H of the reaction decreased from 89.3% due to
further conversion of the desired product to 1A2A. In addition, the
results presented that the catalyst had a distinct catalytic kinetic pro-
cess for 2A1H,1A2H and 1A2A.
Supplementary material related to this article can be found, in the
online version, at doi:https://doi.org/10.1016/j.mcat.2019.110539.
References
[1] S. Bähn, S. Imm, L. Neuber, M. Zhang, H. Neumann, M. Beller, ChemCatChem 3
(2011) 1853–1864.
[
2] S. Thiyagarajan, L. Gootjes, W. Vogelzang, J.V. Haveren, M. Lutz, S.E. Daan,
ChemSusChem 4 (2011) 1823–1829.
[3] J.P. Wolfe, S. Wagaw, J.F. Marcoux, S.L. Buchwald, Acc. Chem. Res. 31 (1998)
05–818.
4] M. Orlandi, D. Brenna, R. Harms, S. Jost, M. Benaglia, Org. Process Res. Dev. 22
2018) 430–445.
8
According to the above test results and the relative process reported
[
[
15–24,35–37], the catalytic dehydrogenation of the hydroxyl group
(
was recognized as the key step prompted by the excellent dehy-
drogenation property of cobalt. However, the single cobalt was unable
to complete the selective amination of 1,2-propanediol. Therefore the
presence of basic lanthanum oxide was required to complete the se-
lectively catalytic reaction (Fig. 6). So, it could be interpreted that the
dehydrogenation process was performed on the Co-La-O interface
where the higher acidity of the secondary hydrogen with respect to the
primary hydrogen resulted in the reaction selectivity based on the ba-
sicity of the catalyst. GCeMS analysis of the product showed no in-
termediate ketone, thus the Co-H species was formed after the catalytic
reaction dehydrogenation on the Co at the interface. This species had
been confirmed through experimentation [38]. After dehydrogenation,
the active intermediate reacted with ammonia to form an imine group
which was then hydrogenated by Co-H to obtain the aminatived pro-
duct.
[5] G. Hibert, O. Lamarzelle, L. Maisonneuve, E. Grau, H. Cramail, Eur. Polym. J. 82
(2016) 114–121.
[
[
[
6] E. Bemooud, C. Leporl, M. Mellah, E. Schulz, J. Hannedouche, Catal. Sci. Technol. 5
(2015) 2017–2037.
7] G.F. Liang, A.Q. Wang, L. Li, G. Xu, N. Yan, T. Zhang, Angew. Chem. Int. Ed. 56
(2017) 3050–3054.
8] W.P. Deng, Y.Z. Wang, S. Zhang, K.M. Gupta, M.J. Hülsey, H. Asakura, L.M. Liu,
Y. Han, E.M. Karp, G.T. Beckham, P.J. Dyson, J.W. Jiang, T. Tanaka, Y. Wang,
N. Yan, Proc. Natl. Acad. Sci. U. S. A. 115 (2018) 5093–5098.
[9] A. Cornejo, B.M. Campoy, J. Lázaro, B. Navarrete, Renew. Sustain. Energy Rev. 79
2017) 1400–1413.
(
[
[
10] B. Katryniok, S. Paul, F. Dumeignil, ACS Catal. 3 (2013) 1819–1834.
11] Y.C. Zhang, F.Z. Sun, H.Y. Zhang, G.H. Ying, J.Q. Zhao, Ind. Eng. Chem. Res. 57
(2018) 4553–4556.
12] Q. Yang, Q.F. Wang, Z.K. Yu, Chem. Soc. Rev. 44 (2015) 2305–2329.
13] D. Pingen, M. Lutz, D. Vogt, Organometallics 33 (2014) 1623–1629.
14] L.L.R. Lorentz-Petersen, L.U. Nordstrϕm, R. Madsen, Eur. J. Org. Chem. 2012
(2012) 6752–6759.
[
[
[
[
[
15] C.R. Ho, V. Defalque, S. Zheng, A.T. Bell, ACS Catal. 9 (2019) 2931–2939.
16] F. Du, X. Jin, W.J. Yan, M. Zhao, P.S. Thapa, R.V. Chaudhari, Catal. Today 302
(
2018) 227–232.
17] G.F. Liang, Y.G. Zhou, J.P. Zhao, A.Y. Khodakov, V.V. Ordomsky, ACS Catal. 8
2018) 11226–11234.
18] M.R. Ball, T.S. Wesley, K.R. Rivera-Dones, G.W. Huber, J.A. Dumesic, Green Chem.
0 (2018) 4695–4709.
19] J. Ibáñez, M. Araque-Marin, S. Paul, M. Pera-Titus, Chem. Eng. J. 358 (2019)
620–1630.
[
[
[
4
. Conclusions
(
2
Cobalt-based catalysts can be prepared by the liquid-phase reduc-
tion, resulting in simple cobalt with dehydrogenation ability and tun-
able catalytic performance based on support modification. Co/La
1
3
O
4
[20] T. Ajay, W. Frédéric, P. Cédric, J.-F. Pau, E. Monflier, M. Pera-Titus, A. Ponche, J.
Catal. 356 (2017) 111–124.
presented an effective catalytic activity for the amination of 1,2-pro-
panediol, indicating that catalytic activity was related to the catalyst
with the special structure derived from the preparation method. The
catalyst prepared by liquid-phase reduction had an efficient active
species for the selective amination of 1,2-propanediol. Compared with
the catalyst prepared by co-precipitation method reported in the lit-
erature [25], not only was the surface area enhanced, but also catalytic
active species were found directly present in the interface of the sup-
port. As a result, the efficiency of the catalytic reaction was improved.
In addition, the reaction conditions were relatively mild. In future
work, the improvement of the catalyst based on its active species will be
key to further enhancement of catalytic dehydration and condensation
[
21] Y.Z. Wang, S.Y. Furukawa, Z. Zhang, L. Torrente-Murciano, S.A. Khan, N. Yan,
Catal. Sci. Technol. 9 (2019) 86–96.
[22] S.Z. Li, M. Wen, H. Chen, Z.L. Ni, J. Xu, J.Y. Shen, J. Catal. 350 (2017) 141–148.
[
[
23] A. Tomer, Z. Yan, A. Ponchel, M. Pera-Titus, J. Catal. 356 (2017) 133–146.
24] F. Du, X. Jin, W.J. Yan, M. Zhao, P.S. Thapa, R.V. Chaudhari, Catal.Today 302
(2018) 227–232.
[25] Y. Ichikawa, Fuchu, E. Yoshisato, K. Nakagawa, US4151204A, 1979.
[
[
26] J. Niemeier, R.V. Engel, M. Rose, Green Chem. 19 (2017) 2839–2845.
27] B. Hu, W.-G. Kim, T.P. Sulmonetti, M.L. Sarazen, S. Tan, J. So, Y.J. Liu, R.S. Dixit,
N.S. Christopher, W. Jones, ChemCatChem 9 (2017) 3330–3331.
[28] F. Niu, S.H. Xie, M. Bahri, O. Ersen, Z. Yan, B.T. Kusema, M. Pera-Titus,
A.Y. Khodakov, ACS Catal. 9 (2019) 5986–5997.
[
29] C.J. Yue, M.M. Gan, L.P. Gu, Y.F. Zhuang, J. Taiwan Inst. Chem. E. 45 (2014)
443–1448.
1
5

C.-J. Yue, et al.
Molecular Catalysis 477 (2019) 110539
[30] C.J. Yue, L.P. Gu, Y. Su, S.P. Zhu, React. Kinet. Mech. Catal. 111 (2014) 633–645.
[31] F. Guo, H.G. Zheng, Z.P. Yang, Y.T. Qian, Mater. Lett. 56 (2002) 906–909.
[32] Z. Li, Y.S. Jin, Q.J. Yan, J. Fuel Chem. Technol. 24 (1996) 191–197.
[33] F. Zhang, Z.Y. Li, S.H. Zhang, N. Akter, R.M. Palomino, D. Vovchok, I. Orozco,
D. Salazar, J.A. Rodriguez, J. Llorca, J. Lee, D. Kim, W.Q. Xu, A.I. Frenkel, Y.Y. Li,
T. Kim, S.D. Senanayake, ACS Catal. 8 (2018) 3550–3560.
[35] T. Takanashi, M. Tamura, Y. Nakagawa, K. Tomishige, RSC Adv. 4 (2014)
28664–28672.
[36] Y. Duan, S.N. Sun, S.B. Xi, X. Ren, Y. Zhou, G.L. Zhang, H.T. Yang, Y.H. Du, Z.J. Xu,
Chem. Mater. 29 (2017) 10534–10541.
[37] S. Song, Y.Z. Wang, N. Yan, Mol. Catal. 454 (2018) 87–93.
[38] R.G. Zhang, W. Huang, B.J. Wang, Chem. J. Chinese U 30 (2009) 2252–2257.
[34] H.M. Liu, G.L. Wei, Z. Xu, P. Liu, Y. Li, Appl. Surf. Sci. 389 (2016) 438–446.
6