Base-free atmospheric O2-mediated oxidation of 5-Hydroxymethylfurfural to 2,5-Furandicarboxylic acid triggered by Mg-bearing MTW zeolite supported Au nanoparticles

Article abstract of DOI:10.1016/j.apcata.2021.118106

Mg-bearing MTW silicalite zeolite, MgSi-ZSM-12, was straightforwardly synthesized by involving an unusual acidic pre-gelation system and engaged as the task-specific support for loading the Au nanoparticles (NPs). The resulting Au/MgSi-ZSM-12 catalyst showed stably excellent activity for the oxidation of HMF into FDCA in the presence of atmospheric dioxygen (O₂) without externally adding any liquid base, affording a yield of 87 % and turnover number (TON) of 331 based on the surface Au sites. Superior basicity was evidenced by embedding Mg species into the all-silica zeolitic skeleton, which enables strong, weak, and near-zero affinity towards aldehyde, alcohol, and carboxyl groups, respectively, thus, allows rapid and high-uptake adsorption of HMF, but negligible adsorption of FDCA. This unique feature of the Mg-bearing all-silica zeolite support together with its synergy with the active sites of Au NPs is revealed to accelerate the production of FDCA under the base-free mild condition.

Full text of DOI:10.1016/j.apcata.2021.118106

Applied Catalysis A, General 616 (2021) 118106
Contents lists available at ScienceDirect
Applied Catalysis A, General
journal homepage: www.elsevier.com/locate/apcata
Base-free atmospheric O2-mediated oxidation of 5-Hydroxymethylfurfural
to 2,5-Furandicarboxylic acid triggered by Mg-bearing MTW zeolite
supported Au nanoparticles
,
,
Lei Chena 1, Wenxia Zhuanga 1, Jingmin Lana, Xiaoling Liua, Shi Jianga, Lei Wangb,
,
,
Yu Zhoua *, Jun Wanga *
a State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing, 211816, China
b School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, 211816, China
A R T I C L E I N F O
A B S T R A C T
Keywords:
Mg-bearing MTW silicalite zeolite, MgSi-ZSM-12, was straightforwardly synthesized by involving an unusual
acidic pre-gelation system and engaged as the task-specific support for loading the Au nanoparticles (NPs). The
resulting Au/MgSi-ZSM-12 catalyst showed stably excellent activity for the oxidation of HMF into FDCA in the
presence of atmospheric dioxygen (O2) without externally adding any liquid base, affording a yield of 87 % and
turnover number (TON) of 331 based on the surface Au sites. Superior basicity was evidenced by embedding Mg
species into the all-silica zeolitic skeleton, which enables strong, weak, and near-zero affinity towards aldehyde,
alcohol, and carboxyl groups, respectively, thus, allows rapid and high-uptake adsorption of HMF, but negligible
adsorption of FDCA. This unique feature of the Mg-bearing all-silica zeolite support together with its synergy
with the active sites of Au NPs is revealed to accelerate the production of FDCA under the base-free mild
condition.
2,5-furandicarboxylic acid
Au/MgSi-ZSM-12
Base-free
Atmospheric di-oxygen
1. Introduction
of mainly three functional groups (hydroxyl, aldehyde and carboxyl
group) in a tandem reaction process [23,24]. Both homogeneous and
With the depletion of fossil resources and the green-house gas
emission resultant environmentally unfriendly effects, growing concerns
have been paid on the production of fuels and chemicals from abundant,
low-cost and renewable biomass [1–6]. In this field, the conversion of
biomass platform molecules provides an important bridge to narrow the
gap between the fossil resource and biomass. 5-hydroxymethyl furfural
(HMF) obtained from carbohydrates is among the most widely investi-
gated platform compounds to produce diverse synthetic drugs and in-
dustrial chemicals [7–11]. Much ink has been spilled about the synthesis
of value-added compounds from HMF via oxidation, hydrogenation, and
so on [12–16]. Among them, the oxidation of HMF yields a valuable
product 2,5-furandicarboxylic acid (FDCA), which is significant for the
production of bio-based polymers as the promising alternative of ter-
ephthalic acid (TPA) [17–22]. However, construction of a highly effec-
tive heterogeneous catalyst for the target oxidation of HMF into FDCA
under mild condition still remains challenges.
heterogeneous catalysts have been developed by using dioxygen (O2) as
the easily available oxidizing agent. Certain homogeneous systems
exhibited high activity under mild condition [25,26]; for example, an
FDCA yield of 95 % was obtained over a homogeneous Pt@PVP catalyst
at 80 ◦C and 1 bar O2 pressure without a liquid base as the additive [25].
As an alternative, heterogeneous catalysts are preferred because of the
facile separation, recovering and operation process [27,28]. Nonethe-
less, the product FDCA is readily adsorbed on the solid surface to
deactivate the catalyst, for which a liquid base is usually added into the
reaction system to increase the solubility of FDCA. Therefore, externally
charging a liquid base additive is a common approach for promoting the
activity of a heterogeneous catalyst, wherein the formation of alkoxide
–
and activation of O H and C–H bonds are accelerated [29,30]. In this
regard, harsh conditions such as high temperature and high pressure
were required in many cases to proceed the conversion smoothly [31,
32]. If in a more difficult base-free system, high pressure of O2 was
normally demanded for the efficient conversion [1,23]. The surface acid
Generally, oxidation of HMF into FDCA involves the transformation
* Corresponding authors.
E-mail addresses: njutzhouyu@njtech.edu.cn (Y. Zhou), junwang@njtech.edu.cn (J. Wang).
1
These authors contributed equally.
https://doi.org/10.1016/j.apcata.2021.118106
Received 24 November 2020; Received in revised form 21 February 2021; Accepted 12 March 2021
Available online 16 March 2021
0926-860X/© 2021 Elsevier B.V. All rights reserved.

L. Chen et al.
Applied Catalysis A, General 616 (2021) 118106
and/or base properties were found to significantly affect the activity by
determining the varied affinities towards the reactant, intermediate and
product in the conversion of HMF into FDCA [33,34]. Solid base mate-
rials were reported as capable carries to support noble metal NPs to
catalyze the base-free synthesis of FDCA from HMF [35–37]. For
instance, N-doped carbon supported Pt catalyst was active in the
oxidation of HMF into FDCA with the N species serving as the moderate
basic sites, which however was only workable under the pressured O2 of
10 bar [36]. Several hydrotalcite (HT) supported Au or Pd NPs allowed
the oxidation of HMF into FDCA with atmospheric O2 under base-free
condition [38], but the inevitable dissolution of HT occurred during
the reaction.
was purchased from Shanghai RongLi Chemical Reagent Co. Ltd.
2.2. Characterization
Powder X-ray diffraction (PXRD) patterns were collected on a
SmartLab diffractometer with Nickel-filtered Cu Kα radiation at a 2θ
range of 5~50◦ (40 kV, 100 mA, 0.2◦/s). High-resolution PXRD patterns
of Si-ZSM-12 and MgSi-ZSM-12 were collected on a SmartLab 9 kW
diffractometer with transmission geometry (capillary: 0.7 mm, angle
range: 5ꢀ 90º, step size: 0.015◦) and applied in the Rietveld refinement,
which was performed by using TOPAS 5.0 Academic suite. Nitrogen
sorption isotherms were recorded on a BEL SORP-MINI analyzer. The
pore size dispersion curves were calculated by using Barrett-Joyner-
Halenda (BJH) and Horvath-Kawazoe (HK) methods. Scanning elec-
tron microscope (SEM) images were taken from a Hitachi S-4800 field-
emission scanning electron microscope. Transmission electron micro-
scope (TEM) images were obtained from a Hitachi JEOL JEM-2100 F
field-emission transmission electron microscope at 200 kV. Fourier
transform infrared spectroscopy (FT-IR) spectra were measured on an
Agilent Cary 660 Infrared spectrometer. Ultraviolet visible (UV–vis)
diffuse reflection spectra were detected on a SHIMADZU UV-2600
spectrometer by using barium sulfate (BaSO4) as the internal standard.
Inductively coupled plasma emission spectrometry (ICP) was performed
on an ICP OPTMA 20,000 V analyzer. X-ray fluorescence (XRF) analysis
was performed by Rigaku ZSX Primus II. A PHI 5000 Versa Probe X-ray
photoelectron spectrometer was used for the X-ray photoelectron spec-
troscopy (XPS) analyses. Carbon monoxide (CO) chemisorption (pulse
titration) and carbon dioxide temperature programmed desorption
(CO2-TPD) measurements were conducted on a JAPAN BELCAT-B
Analyzer instrument. Thermogravimetric analysis (TGA) was carried
out on an STA 409 instrument in air (10 ◦C minꢀ 1).
Zeolites are widely applied supports constructed from TO4 tetra-
hedra (T = Si or Al), due to the ordered and porous crystal structure plus
the high thermal and hydrothermal stability [39–41]. Normally,
aluminosilicate forms of zeolites have been used as solid acid catalysts,
adsorbents, and ion exchangers [42–44]. In 2013, Au nanoclusters were
confined in the supercage of Y zeolite for the oxidation of HMF to FDCA,
yet sodium hydroxide was used as the base additive [45]. Recently, Pd
NPs encapsulated in BEA zeolite offered the high yield and large turn-
over number (TON) in this reaction with the adding of liquid base so-
dium carbonate [46]. Heteroatomic zeolites can extend the intrinsic
physical and chemical properties by combining the feature of the
embedded heteroatoms [47–51]. Previous literatures indicate that
incorporation of alkali earth metal atoms like Mg into zeolite framework
enhanced materials’ basicity that can effectively catalyze Knoevenagel
condensations and CO2 cycloaddition with epoxides [49,52]. However,
none of them has been employed as the supports of noble metals, let
alone their application in the base-free selective oxidation of biomass
platform molecules.
In this work, we illustrate the direct synthesis of Mg-bearing all-silica
ZSM-12 zeolite (shorten as MgSi-ZSM-12), on which the Au NPs were
supported to give the catalyst Au/MgSi-ZSM-12. ZSM-12 is an MTW
topological zeolite with one-dimensional and straight elliptical 12-
membered ring channels [52,53], The task-specific MgSi-ZSM-12 solid
base support herein was hydrothermally synthesized with an unusual
acidic pre-gelation system, in which the Mg and Si sources were
co-hydrolyzed and co-condensed in weak acidic environment to
strengthen the interaction of Mg ions and silica precursor for the purpose
of embodying the Mg species [52]. The resulting Au/MgSi-ZSM-12
showed a stably excellent activity in the synthesis of FDCA from the
oxidation of HMF with atmospheric O2 in the absence of any extra liquid
base. To gain insight into the influence of zeolites’ framework compo-
sition on the activity, the neat all-silica ZSM-12, as well as Mg-/Al--
bearing ZSM-12, were synthesized as the control supports to load the Au
NPs. Apart from the comprehensive characterizations of the supports
and catalysts series, their adsorption behavior of the reactant, in-
termediates and product were systematically investigated, which un-
ravels the unique role of the intrinsic base properties of the supports in
remarkably accelerating the production of FDCA.
2.3. Materials synthesis
Mg-bearing siliceous MTW zeolites (MgSi-ZSM-12) were synthesized
in a one-pot hydrothermal route with Si/Mg molar ratio of 50 (20, or
100) in the gel by referring our previous work [52]. Mg- and
Al-containing ZSM-12 with the SiO2/Al2O3 molar ratio of 600, named as
Mg-ZSM-12(600), was synthesized similarly with the gel composition of
1 SiO2: 0.02 Mg: 0.00125 Al2O3: 0.35 TEAOH: 22.5 H2O.
Pure silica MTW zeolite, termed as Si-ZSM-12, was synthesized in the
absence of Mg species with the similar procedure. After the acid-
hydrolysis step, the water was removed through evaporation to pro-
duce powder that was additionally dried at 100 ◦C for 4 h. The powder
was mixed with 8 g TEAOH and then the mixture was aged at room
temperature for 24 h, with the pH controlled at ~12 by adding NaOH.
The gel with the molar composition of 40 SiO2: 8TEAOH: 320 H2O was
transferred into Teflon-lined stainless-steel autoclave and crystallized at
◦
140 C for 7 d. The as-synthesized sample Si-ZSM-12-as was obtained
with the same procedure as that of MgSi-ZSM-12. Template was
removed similarly to offer the sample Si-ZSM-12.
Au NPs supported samples, named as 1%Au/support (the supports
covered MgSi-ZSM-12, Mg-ZSM-12(600), Si-ZSM-12, SiO2, Al2O3, and
MgO), were prepared through deposition-precipitation (DP) method. 1
mL HAuCl4 aqueous solution containing 0.01 g HAuCl4 was mixed with
0.25 g support, and then NH3⋅H2O solution was added to adjust the pH
(~9), followed by stirring at 60 ◦C for 12 h. The solid was isolated by
centrifugation, washed with water, dried, and then reduced under 10 %
H2/90 %N2 flow.
2. Experimental
2.1. Materials and methods
All chemicals were used directly without further purification. Mag-
nesium nitrate (Mg(NO3)2⋅6H2O, 99 wt%), tetraethylorthosilicate
(TEOS, SiO2 of 28.4 wt%), and sodium hydroxide (NaOH, 96 wt%) were
purchased from Sinopharm Chemical Reagent Co., Ltd. Silicon dioxide
(SiO2, 99 wt%), aluminum oxide (Al2O3, 99 wt%) and magnesium oxide
(MgO, 99 wt%) were purchased from China National Pharmaceutical
Group Corporation. Chloroauric acid (HAuCl4, Au of 23.5~23.8 wt%)
was purchased from Aladdin. 5-hydroxymethyl furfural (HMF, 97 wt%)
was purchased from Energy Chemical. Hydrochloric acid (HCl, 36.5 wt
%) was purchased from Shanghai LingFeng Chemical Reagent Co. Ltd.
Tetraethylammonium hydroxide (TEAOH, 35 wt% aqueous solution)
2.4. Synthesis of FDCA from HMF
The transformation of HMF into FDCA was carried out in a 25 mL
reaction tube equipped with an oxygen (O2) balloon. 0.1 mmol HMF was
added into the tube containing 4 mL water, followed by the addition of
0.1 g catalyst. The reaction mixture was stirred at 90 ◦C for preset time.
2

L. Chen et al.
Applied Catalysis A, General 616 (2021) 118106
After the reaction, the liquid phase was separated by centrifugation and
diluted with water. High performance liquid chromatography (HPLC,
Thermo Scientific UltiMate3000) equipped with Ultraviolet detector
para-nitroaniline (pNA) loaded pure silica ZSM-12 (pNA-ZSM-12) as the
model (a=24.89 Å, b=5.00 Å, c=24.25 Å, β=107◦, space group C12/c1)
[55]. Similar phenomenon was observed in the structure refinement of
previous pure silica ZSM-12, in which there existed a well-ordered
arrangement of tetraethylammonium (TEA) cations in the channel.
The size mismatch between guest TEA molecule (5.5 × 7.3 × 7.3 Å) and
host zeolite unit cell parameter (24.8 × 5.0 × 24.3 Å) resulted in a
super-structure along the b-axis. In Kasunic’s work, many trial structures
were constructed to reach the reasonable arrangement of the TEA
molecules without any short contact distances between each other,
sequentially the space group was lowered from C2/c to Cc with three
times larger b unit cell (~15.1903 Å) to give the initial structure model
[56]. Thus, an improved model was generated in Platon routine with
parameter: a=25.2177 Å, b=15.1903 Å, c=24.4754 Å, and β=108.516◦
in space group Cc was used in the Le Bail fitting, producing good
agreement of the calculated pattern with the observed ones (Rwp: 4.4 %)
(Fig. S4). Accordingly, the reasonable distribution of TEA cations with tt.
tt conformation in our work was located by the simulated annealing
process, showing that eight TEA cations occluded in the super-structure
along b-axis, in line with the empirical formula in Table S1. Rietveld
refinement was performed with the final model to reach the maximum
and Capillary column (Arcus EP-C18, 5 μm, 4.6 × 250 mm) was used to
analyze the composition of the collected liquid phase, with a flowing
phase of 50 % water and 50 % methyl alcohol (0.5 mL minꢀ 1). The
collected catalyst was washed with ethyl alcohol, dried at 60 ◦C and then
charged into the next run to measure the reusability in a five-run test.
Conversion of HMF = (mmol HMF converted)/(mmol HMF initial)×
100. Yield of FDCA = (mmol FDCA)/(mmol initial HMF)×100. The er-
rors in conversion and yield were calculated to be within ± 2%. Turn-
over number (TON)
= (mmol FDCA)/[(mmol Au)×dispersion].
Turnover frequencies (TOF) = (mmol FDCA)/[(mmol Au)×dispersion ×
reaction time].
2.5. Adsorption of different substrates
Adsorption of 5-hydroxymethylfurfural (HMF), 5-hydroxymethyl-2-
furancarboxylic acid (HMFCA) and 5-formyl-2-furancarboxylic acid
(FFCA) and 5-furandicarboxylic acid (FDCA) on different adsorbents
was performed in a 10 mL tube. A mixture of 0.1 g adsorbent, 0.01 mmol
adsorbates and 4 mL water was stirred at room temperature for 24 h.
After that, the liquid phase was isolated by centrifugation and analyzed
by HPLC.
agreement between calculated patterns and the observed ones (Rwp
:
10.9 %). The refined crystal structure of Si-ZSM-12-as is deposited in
Fig. 1A. Owing to the iso-electronic property of Mg and Si, we evenly
distributed Mg at the tetrahedral sites in the structure refinement of
MgSi-ZSM-12-as. The final result derived by Rietveld refinement (Rwp
:
3. Results and discussion
8.7 %) in Fig. 1B shows almost the same structure for MgSi-ZSM-12-as as
that for Si-ZSM-12-as. Specifically, the unique arrangement of TEA in
MgSi-ZSM-12-as and Si-ZSM-12-as suggests the same structure-directing
function of TEA in the hydrothermal crystallization of the two samples.
The unit cell parameters of Si-ZSM-12-as are a = 25.2403(8) Å, b =
15.1670(6) Å, c = 24.4801(8) Å, β = 108.449(6) ◦ (Entry 1, Table S1).
The longer bond of Mg ꢀ O (~2.10 Å) than Si ꢀ O (~1.61 Å) results in
subtle expanded unit cell size of MgSi-ZSM-12 [a = 25.2365(7) Å, b =
15.1691(6) Å, c = 24.4833(8) Å, β = 108.463(3) ◦].
3.1. Construction of Au NPs on MgSi-ZSM-12
Scheme 1 shows the synthetic procedure of Mg-bearing all-silica
ZSM-12 zeolite (MgSi-ZSM-12). For comparison, pure silica ZSM-12 (Si-
ZSM-12) was synthesized following the modified strategy without
involving the Mg source (Scheme S1). The unit cell compositions of Si-
ZSM-12-as and MgSi-ZSM-12-as (Table S1) were calculated from the
combination of XRF and TG analyses (Fig. S1). High-resolution XRD
patterns of Si-ZSM-12-as and MgSi-ZSM-12-as were collected for struc-
ture refinement. When the structure parameters of calcined pure-silica
ZSM-12 in the International Zeolite Association (IZA) structure data-
base were chosen as the initial point for Le Bail fitting [54], it leads to a
large deviation of the fitted patterns from the observed ones (Fig. S2).
Furthermore, these unindexed diffraction peaks disappeared after
calcination (Fig. S3). Such deviation was also found by employing
After the high temperature calcination to remove the template TEA,
the Au NPs were loaded onto MgSi-ZSM-12 through DP method. XRD
patterns of MgSi-ZSM-12 and 1%Au/MgSi-ZSM-12 (Fig. 2A) show that
the diffraction peaks from TEA cations mentioned above disappeared.
No diffraction peak for Au NPs was found, meaning a high dispersion of
Au NPs. As measured by ICP (Table 1), Au content was consistent with
the theoretical value. Fig. 2B shows N2 sorption isotherms of MgSi-ZSM-
Scheme 1. Schematic representation of the synthesis of Au NPs supported on MgSi-ZSM-12.
3

L. Chen et al.
Applied Catalysis A, General 616 (2021) 118106
Fig. 1. Observed (blue), calculated (red), and difference (gray) profiles for the Rietveld refinement of (A) Si-ZSM-12-as and (B) MgSi-ZSM-12-as. The inset is the
arrangement pictures of TEA cations within the channels of Si-ZSM-12-as and MgSi-ZSM-12-as viewing along b-axis (blue: Mg and/or Si, red: O) (For interpretation of
the references to colour in this figure legend, the reader is referred to the web version of this article).
Fig. 2. (A) PXRD patterns and (B) N2 sorption isotherms of MgSi-ZSM-12 and 1%Au/MgSi-ZSM-12.
12 (Fig. 3A) illustrates small tablet-like primary crystals with the size
Table 1
ranging from tens to hundreds of nanometers, which aggregated to form
Textural properties of different catalyst.
secondary particles shaped of the rice grainy and finally highly fused
b
c
Entry
Catalyst
Aua (wt %)
SBET
Vp
into loosely packed particles in tens of micrometers level. The
morphology of 1%Au/MgSi-ZSM-12 resembles its parent support MgSi-
ZSM-12 [52], suggesting that the DP loading process could not affect
zeolite morphology significantly. By contrast, Si-ZSM-12 was composed
of closely packed trigonal prisms with the size of several micrometers
(Figure S8). Uniform distribution of Si, O, Mg, Au was observed on the
corresponding elemental mapping images (Fig. 3C). TEM image
(Fig. 3B) of 1%Au/MgSi-ZSM-12 presents a relatively narrow dispersion
of Au NPs with an average particle size of 3.9 nm. Quantitatively, CO
chemisorption in Table 2 gives the metal dispersion for 1%Au/Mg-
Si-ZSM-12 of 5.1 % (Entry 2), slightly lower than that for 1%
Au/Si-ZSM-12 (8.6 %) (Entry 3).
(m2 gꢀ 1
)
(cm3 gꢀ 1
)
1
2
3
4
5
6
7
MgSi-ZSM-12
–
312
278
289
293
341
176
4
0.41
0.35
0.36
0.44
0.92
0.26
–
1%Au/MgSi-ZSM-12
1%Au/Si-ZSM-12
1%Au/Mg-ZSM-12(600)
1%Au/SiO2
1.02
0.95
0.98
0.85
0.89
0.92
1%Au/Al2O3
1%Au/MgO
a
b
c
Au contents measured by ICP.
Surface area.
Total pore volume. “-” means the pore volume of 1%Au/MgO is negligible.
For these samples, almost the same FT-IR spectra (Figs. S9 and S10)
were observed, showing the absorption bands at 1220, 1070 and 796
cmꢀ 1 for the external asymmetric stretch vibration, internal asymmetric
stretch vibration and external symmetric stretch vibration of tetrahe-
dron, respectively [57]. UV–vis spectra of Au-containing MgSi-ZSM-12
(Figure S11) exhibited a slight absorption between 500 and 600 nm
belonging to the typical plasmon band of Au NPs [58], further revealing
a good dispersion. XPS analysis was performed to figure out the valence
state of Au NPs (Figs. 4A and S12). The survey scan XPS spectrum of
Au/MgSi-ZSM-12 shows the signals at 285 eV, 533 eV, 84 eV, and 104
eV for C1s, O1s, Au4f, and Si2p, respectively. The high-resolution Au4f
12 and 1%Au/MgSi-ZSM-12. Both exhibited an International Union of
Pure and Applied Chemistry (IUPAC) type-I N2 sorption isotherm, sug-
gesting the formation of typical microchannels. Compared with Si-ZSM-
12 (Fig. S5), a small H3 type hysteresis loop was observed in the nitrogen
sorption isotherms of these Mg-containing samples, manifesting the
formation of certain mesopores, mostly due to the packing of the pri-
mary zeolitic crystals. Pore size distribution curves in Figs. S6 and S7
also reveal this variation after the introduction of Mg species. As sum-
marized in Table 1, slight decrease in surface areas and pore volumes
was observed after Au loading, however, these Au-containing zeolites
demonstrated still high surface areas. SEM image of 1%Au/MgSi-ZSM-
4

L. Chen et al.
Applied Catalysis A, General 616 (2021) 118106
Fig. 3. SEM images of (A) 1%Au/MgSi-ZSM-12. (B) TEM image of 1%Au/MgSi-ZSM-12. (C) SEM elemental mapping images of Si, O, Mg, and Au of 1%Au/MgSi-
ZSM-12.
Table 2
Oxidation of HMF into FDCAa.
Basic siteb
(mmol gꢀ 1
Conv.
(%)
Yield (%)
HMFCA
Entry
Catalyst
Au dispersionc(%)
TONd
TON
TOF
Carbon balance (%)
)
FFCA
FDCA
1
MgSi-ZSM-12
1.45
–
8.0
>99
32
4.1
9.2
25
1.3
2.0
4.2
5.9
7.1
3.1
7.9
0.1
5.1
8.6
2.8
2.0
87
0
–
–
–
92.5
98.3
91.3
99.3
89.6
98.5
98.8
99.2
99.2
95.5
89.0
2
1%Au/MgSi-ZSM-12
1%Au/Si-ZSM-12
1%Au/Mg-ZSM-12(600)
1%Au/SiO2
1.24
5.1
8.6
4.7
4.1
3.4
5.2
8.6
8.6
8.6
8.6
17
0
331
0
14
0
3
< 0.1
0.89
4
62
32.7
35
23
0
4.7
0
100
0
4.2
0
5
< 0.1
< 0.1
1.3
47
6
1%Au/Al2O3
20
12.6
78
4.0
7.0
98
76
13
1.0
0.9
1.5
20
16
2.7
0.2
26.5
28.8
237
184
31.4
2.30
1.1
1.2
9.9
7.6
1.3
0.1
7
1%Au/MgO
94
8e
9f
10g
11h
1%Au/Si-ZSM-12
1%Au/Si-ZSM-12
1%Au/Si-ZSM-12
1%Au/Si-ZSM-12
< 0.1
< 0.1
< 0.1
< 0.1
>99
99
1.1
18
98
72
20
14
a
Reaction condition: HMF 0.1 mmol, HMF/metal molar ratio = 20:1, water 4 mL, 90 ◦C, 24 h, O2 balloon.
b
c
d
e
f
The density of basic sites measured by CO2-TPD.
Metal dispersion was estimated by CO chemisorption.
Turnover number (TON)=(mmol FDCA)/(mmol Au).
With the addition of equal molar Mg(OH)2.
With the addition of equal molar MgO.
g
h
With the addition of equal molar Mg(OH)2 and filtrated after 8 h.
With the addition of equal molar Mg(NO3)2. “-” means the value is unavailable.
Fig. 4. (A) Au 4f XPS spectrum of 1%Au/MgSi-ZSM-12. (B) CO2-TPD curves of MgSi-ZSM-12 and 1%Au/MgSi-ZSM-12.
5

L. Chen et al.
Applied Catalysis A, General 616 (2021) 118106
spectrum was fitted with two peaks at 83.8 eV (4f5/2) and 87.5 eV (4f7/2
)
the whole reaction, slight accumulation of FFCA below 20 % was
observed. Nearly complete conversion of HMF was achieved at 8 h and
then HMFCA was gradually converted into FFCA and finally FDCA. This
phenomenon indicates that the oxidation of the first aldehyde group into
carboxyl group is a rapid step while the transformation of the hydroxyl
group into aldehyde group in the oxidation of HMFCA into FFCA ex-
hibits as the rate-determining step. This kinetic process is in line with
that in the presence of a base as the additive the Au NPs facilitates the
oxidation of aldehyde group [62,63]. Therefore, it is rational to reason
that the incorporated Mg species serve as a solid base that promotes the
conversion of HMF into FDCA. To confirm this speculation, MgO and Mg
(OH)2 were employed as the solid base additive in the 1%Au/Si-ZSM-12
catalyzed oxidation of HMF into FDCA. As shown in Table 2, the yield of
FDCA reached 98 % and 76 % in the presence of equal molar Mg(OH)2
and MgO, respectively (Entries 8–9). Normally, the involving of MgO
and Mg(OH)2 in an aqueous solution would inevitably cause the leach-
ing of Mg2+ [38]. The detected Mg content in the liquid phase after
reaction was 9 ppm, suggesting that 37 % of Mg(OH)2 had been dis-
solved. However, the yield dropped to 13 % if the solid part of slurry
mixture was filtrated and allowed the reaction with the addition of fresh
1%Au/Si-ZSM-12 (Entry 10, Table 2). This phenomenon excluded the
contribution of leached Mg species, which is further confirmed by the
inert activity of 1%Au/Si-ZSM-12 in the presence of Mg(NO3)2 (Entry
11, Table 2). All these results indicate that the high activity of 1%
Au/MgSi-ZSM-12 comes from the synergy of Au NPs and internal solid
base property of the support MgSi-ZSM-12.
for the Au0 species, revealing that the Au species existed dominantly in
the form of metallic state [59]. Notably, the signal at 89.6 eV attribut-
able to Mg2s also occurred explicitly (Fig. 4A) [60]. CO2 TPD profiles for
1%Au/MgSi-ZSM-12 and MgSi-ZSM-12 (Fig. 4B) demonstrate
a
◦
desorption peak, though broad from 100 to 250 C, for the moderate
basic sites; by contrast, only negligible desorption peak appeared for
Si-ZSM-12. The comparison implies that the moderate basicity should
have originated from the incorporation of Mg species. The density of
basic sites was calculated and listed in Table 2, showing the considerably
high density of 1.45 and 1.24 mmol gꢀ 1 for MgSi-ZSM-12 and 1%
Au/MgSi-ZSM-12, respectively.
3.2. Synthesis of FDCA from HMF
MgSi-ZSM-12 supported Au NPs were used as the heterogeneous
catalyst for aerobic oxidation of HMF into FDCA by using atmospheric
O2 as the sole oxygen resource under base-free condition (Table 2). The
support MgSi-ZSM-12 alone gave a very low HMF conversion of 8% and
FDCA yield of 2% (Entry 1). After Au loading, the catalyst 1%Au/MgSi-
ZSM-12 could effectively catalyze the synthesis of FDCA with a yield of
87 % and high TON of 331 (average TOF: 14) based on the surface Au
species (Entry 2). The influence of Mg and Au contents was investigated.
By referring our previous work [52], Mg containing MTW zeolite with
the Si/Mg ratio of 100 in the gel was synthesized and used to support Au
NPs, giving the catalyst 1.0 %Au/MgSi-ZSM-12ꢀ 100 with a yield of 18.1
% for FDCA in the oxidation of HMF into FDCA (Entry 1, Table S2).
Notably, the higher Mg concentration such as Si/Mg = 25 in the gel
caused much weak crystallinity [52]. Therefore, Si/Mg = 50 is the
optimized one. Further, different amount of Au NPs was loaded on
MgSi-ZSM-12. The catalysis evaluation indicated that low Au content of
0.5 % led to a low FDCA yield, while high Au content of 1.5 % gave a
comparable yield to that of 1.0 %Au/MgSi-ZSM-12. These results show
that the champion catalyst is 1.0 %Au/MgSi-ZSM-12 with the initial
Si/Mg ratio of 50 and Au loading of 1.0 %. For comparison, several
control catalysts were prepared and evaluated in parallel. With the
Mg-free support Si-ZSM-12, the sample 1%Au/Si-ZSM-12 exhibited a
feeble activity without generation of FDCA (Entry 3). With the similarly
synthesized Mg and Al co-bearing support of Mg-ZSM-12(600) (Si/Mg =
50, SiO2/Al2O3 = 600) (Fig. S13-S16), the resultant counterpart 1%
Au/Mg-ZSM-12(600) showed the lowered base sites (0.89 mmol gꢀ 1), as
well as a drastically decreased FDCA yield (23 %, Entry 4) compared
with 1%Au/MgSi-ZSM-12. Besides, inert or weak activity (Entries 5–7)
was observed over the Au NPs supported on SiO2, Al2O3 and MgO
(Fig. S17-S19). All of these visualize the unique advantageous feature of
1%Au/MgSi-ZSM-12 in catalyzing the base-free oxidation of HMF to
FDCA with atmospheric O2.
After the reaction, 1%Au/MgSi-ZSM-12 was recovered by centrifu-
gation and reused. In a five-run test, no apparent deactivation was
observed, revealing the stable recycling performance (Fig. 5B). XRD
pattern of the spent 1%Au/MgSi-ZSM-12, shorted as 1%Au/MgSi-ZSM-
12-r, displays the maintaining of the MTW topological crystal structure
(Fig. S20A). Nitrogen sorption isotherm of 1%Au/MgSi-ZSM-12-r is
identical to that of the fresh one, suggesting the preservation of the
porosity (Fig. S20B). Its TEM image and particle size distribution curve
(Fig. S21) shows highly dispersive Au NPs with an average particle size
of 4.1 nm, close to the fresh one (3.9 nm). XPS analysis indicates that
these Au NPs remained in the metallic stage (Fig. S22). The Au content
of 1%Au/MgSi-ZSM-12-r was examined to be 0.96 %, only with a
decrease by 0.06 % compared to the fresh one. The Si/Mg molar ratio
changed from 32.0 in the fresh 1%Au/MgSi-ZSM-12 to 32.6 in the spent
one. All of these demonstrate the stable structure of 1%Au/MgSi-ZSM-
12, responsive to the quite steady recyclability. This robust catalytic
behavior also excludes the potential formation of Mg(OH)2 or MgO
species in MgSi-ZSM-12. In terms of yield, TON and stability, Table S3
presents a comprehensive comparison of 1%Au/MgSi-ZSM-12 with
previous homogeneous and heterogeneous catalysts under different
conditions. There were some efficient heterogeneous catalysts exhibit-
ing high yield and TON using atmospheric O2 but with the assistance of
base additives (NaOH or K2CO3, etc.). Also, there were some catalysts
were active in the base-free oxidation of HMF into FDCA but needing the
use of high pressure O2. Compared with those catalysts operated under
harsh conditions, the present 1%Au/MgSi-ZSM-12 exhibited inferior
yield and TON while giving good recyclability. Compared with the
several previous catalysts operated under atmospheric O2 in the absence
of extra base additive [25,26,33,64,65]. 1%Au/MgSi-ZSM-12 showed
comparable yield/TON and superior recycling performance, attributable
to the internal stability of zeolitic catalysts. In short, the presently
constructed 1%Au/MgSi-ZSM-12 acts as a stable heterogeneous catalyst
for the oxidation of HMF into FDCA that turns out to be active under the
base-free atmospheric O2-mediated mild condition.
In the common cognition, the aerobic oxidation of HMF to FDCA
proceeds via two pathways (Scheme 2), in which either 2,5-diformyl-
furan (DFF) or HMFCA acted as the intermediate in the absence or
presence of a liquid base [60,61], respectively. To figure out the
oxidation pathway of HMF over 1%Au/MgSi-ZSM-12, time-dependence
of the reaction was mapped in Fig. 5A. After the reaction at 90 ◦C for 4 h,
the conversion of HMF reached 95 % with the FDCA yield of 19 %, where
HMFCA was accumulated with the yield of 74 %. Prolonging the time
promoted the conversion of HMF and production of FDCA. Throughout
3.3. Understanding of the catalytic behavior
Taking account of the similar dispersion of Au NPs of 1%Au/MgSi-
ZSM-12 to the other control catalysts, its high activity seems associating
with the specific basic property of the support MgSi-ZSM-12. The inert
Scheme 2. The potential pathways for the oxidation of HMF into FDCA over
1%Au/MgSi-ZSM-12.
6

L. Chen et al.
Applied Catalysis A, General 616 (2021) 118106
Fig. 5. (A) Time-resolved and (B) recyclability for the oxidation of HMF into FDCA over 1%Au/MgSi-ZSM-12; Reaction conditions: HMF 0.1 mmol, HMF/metal
molar ratio = 20:1, water 4 mL, 90 ◦C, O2 balloon.
or weak activity was observed by using the neutral supports of Si-ZSM-
12 and SiO2, the acid support of Al2O3 or the common solid base MgO
with weak base property (Fig. S23). This comparison emphasizes the
vital role of the basic property of the supports, which is further revealed
by the declined activity over 1%Au/Mg-ZSM-12(600).
accumulation of this intermediate reflected by kinetic curves. On the
contrary, acidic Al2O3 adsorbed more FDCA than HMF, and basic MgO
effectively adsorbed all of them. Further, SiO2 and Si-ZSM-12 of neutral
supports and Mg-ZSM-12(600) with both inferior basic sites and certain
Al-derived acidic sites also showed unfavorable adsorption perfor-
mance; weak adsorption was demonstrated for all those organic com-
pounds. Consequently, the adsorption behaviors for the versatile control
supports hamper the HMF adsorption and FDCA leaving, and thus
resulting in much lowered activity. Oxidation of HMF into FDCA was
further carried out in the presence of FDCA with the amounts of 0.01 and
0.02 mmol, respectively, by using the catalysts of 1%Au/MgSi-ZSM-12,
1%Au/Mg-ZSM-12(600) and 1%Au/Si-ZSM-12+MgO. As shown in
Fig. S25, declining yield was observable with the increasing dosage of
FDCA, revealing the inhibition effect of the product. A more significant
effect was found over 1%Au/Mg-ZSM-12(600) than 1%Au/Mg-
Si-ZSM-12, corresponding to the higher adsorption amount over the
former than the latter (Fig. 6A). The weakest influence over 1%
Au/Si-ZSM-12+MgO is assignable to preferential adsorption of acidic
FDCA on basic sites of MgO rather than the relavely neutral 1%
Au/Si-ZSM-12, preserving the active Au species on 1%Au/Si-ZSM-12 to
a large degree. The above analysis on the adsorption behavior allows
drawing that, it by virtue of the superior basicity of the heteroatomic
zeolite MgSi-ZSM-12 that the favorable reactant adsorption and product
desorption are achieved, for which the thus supported Au NPs can
smoothly and effectively catalyze the atmospheric O2-mediated oxida-
tion of HMF into FDCA under the base-free mild condition.
Normally, the acid and/or base properties of solid catalysts signifi-
cantly affect their surficial affinity toward reactant, intermediate and
product, and thus would make a crucial contribution in a heterogeneous
catalytic process [33,34]. Having this in mind, we investigated the
adsorption behavior to unravel the affinity of HMF, HMFCA, FFCA, and
FDCA towards different supports. At the beginning, we compared the
adsorption of HMF, HMFCA, FFCA, and FDCA on MgSi-ZSM-12 at 90 ◦C
(the reaction temperature in the oxidation of HMF into FDCA) and the
room temperature of 25 ◦C (Fig. S24), observing quite similar adsorption
amount. Based on these and the convenience for experimental opera-
tion, the adsorption study was carried out at 25 ◦C. The kinetic
adsorption curves of HMF and FDCA on MgSi-ZSM-12 (Fig. 6A and B)
display a high uptake of HMF and rapid adsorption rate; by contrast,
negligible adsorption amount of FDCA was detected even elongating the
adsorption time up to 24 h. This favorable adsorption towards the
reactant HMF, together with near-zero affinity towards the product
FDCA, is particularly important for the smoothly adhesive access of HMF
catalytic active sites and then the generated FDCA product with better
leaving ability. The low adsorption of HMFCA and moderate adsorption
of FFCA were found on MgSi-ZSM-12, indicating the affinity towards
different groups is in the sequence of aldehyde > alcohol > carboxyl.
The inferior adsorption of HMFCA can be attributable to the repulsive
force towards carboxyl groups, responding to the apparent
Fig. 6. (A) Adsorption amount of HMF, HMFCA, FFCA, and FDCA on different solid. Adsorption condition: adsorbate 0.01 mmol, adsorbent 0.1 g, water 4 mL, 25 ◦C,
24 h. (B) Time-resolved adsorption of HMF and FDCA on MgSi-ZSM-12. To show the Time-resolved adsorption amount more significant, we increased the adsorption
concentration. Adsorption condition: adsorbate 0.01 mmol, adsorbent 0.05 g, water 1 mL, 25 ◦C.
7

L. Chen et al.
Applied Catalysis A, General 616 (2021) 118106
[10] X. Tang, J. Wei, N. Ding, Y. Sun, X. Zeng, L. Hu, L. Lin, Renew. Sustain. Energy Rev.
77 (2017) 287–296.
4. Conclusions
[11] L. Hu, A. He, X. Liu, J. Xia, J. Xu, S. Zhou, J. Xu, ACS Sustain.Chem. Eng. 6 (2018)
15915–15935.
MgSi-ZSM-12 heteroatomic zeolite was directly synthesized in a
hydrothermal route, showing same structure-directing effect of the TEA
template as that of the all-silica Si-ZSM-12 itself. After Mg incorporation,
The basicity of MgSi-ZSM-12 was greatly strengthened due to the in situ
embedding of Mg species. With this solid base MgSi-ZSM-12 as the
support, the resultant Au NPs sized ~3.9 nm effectively catalyzed the
oxidation of HMF into FDCA with atmospheric O2 under base-free
condition. The catalyst was conveniently recovered and reused
without apparent deactivation. We clarify that MgSi-ZSM-12 has suffi-
cient affinity to aldehyde group, weak interaction to alcohol group and
repulsive force to carboxyl. Owing to this unique character, the catalyst
reached desirably preferential adsorption of HMF and facile desorption
of FDCA, responsive to the excellent catalytic performance. This work
highlights the potentially promising application of alkaline-earth metal-
bearing heteroatomic zeolites as the multi-functional supports of noble
metal NPs in biomass conversion field.
[12] H. Wang, C. Zhu, D. Li, Q. Liu, J. Tan, C. Wang, L. Ma, Renew. Sustain. Energy Rev.
103 (2019) 227–247.
[13] S. Shunmugavel, P. Pal, ChemSusChem 12 (2019) 145–163.
[14] X. Qi, R. Zhou, H.-J. Ai, X.-F. Wu, J. Catal. 381 (2020) 215–221.
[15] B. Liu, Z. Zhang, ACS Catal. 6 (2015) 326–338.
[16] S. Wang, Z. Zhang, B. Liu, ACS Sustain. Chem. Eng. 3 (2015) 406–412.
[17] D.-H. Nam, B.J. Taitt, K.-S. Choi, ACS Catal. 8 (2018) 1197–1206.
[18] D. Yan, J. Xin, Q. Zhao, K. Gao, X. Lu, G. Wang, S. Zhang, Catal. Sci. Technol. 8
(2018) 164–175.
[19] A.F. Sousa, M. Matos, C.S.R. Freire, A.J.D. Silvestre, J.F.J. Coelho, Polymer 54
(2013) 513–519.
[20] G.Z. Papageorgiou, V. Tsanaktsis, D.N. Bikiaris, Phys. Chem. Chem. Phys. 16
(2014) 7946–7958.
[21] A.H. Motagamwala, W. Won, C. Sener, D.M. Alonso, C.T. Maravelias, J.A. Dumesic,
Sci. Adv. 4 (2018) eaap9722.
[22] A. Tirsoaga, M. El Fergani, N. Nuns, P. Simon, P. Granger, V.I. Parvulescu, S.
M. Coman, Appl. Catal. B 278 (2020), 119309.
[23] Z. Zhang, G.W. Huber, Chem. Soc. Rev. 47 (2018) 1351–1390.
[24] E. Hayashi, Y. Yamaguchi, K. Kamata, N. Tsunoda, Y. Kumagai, F. Oba, M. Hara,
J. Am. Chem. Soc. 141 (2019) 890–900.
[25] S. Siankevich, G. Savoglidis, Z. Fei, G. Laurenczy, D.T.L. Alexander, N. Yan, P.
J. Dyson, J. Catal. 315 (2014) 67–74.
CRediT authorship contribution statement
[26] S. Siankevich, S. Mozzettini, F. Bobbink, S. Ding, Z. Fei, N. Yan, P.J. Dyson,
ChemPlusChem 83 (2017) 19–23.
Lei Chen: Investigation, Formal analysis, Writing - original draft.
Wenxia Zhuang: Data curation, Formal analysis, Writing - review &
editing. Jingmin Lan: Writing - review & editing, Formal analysis.
Xiaoling Liu: Writing - review & editing, Formal analysis. Shi Jiang:
Writing - review & editing, Formal analysis. Lei Wang: Writing - review
& editing, Formal analysis. Yu Zhou: Conceptualization, Investigation,
Methodology, Supervision, Writing - review & editing. Jun Wang:
Conceptualization, Supervision, Writing - review & editing.
[27] S. Verma, M.N. Nadagouda, R.S. Varma, Sci. Rep. 7 (2017) 13596.
[28] X. Han, C. Li, X. Liu, Q. Xia, Y. Wang, Green Chem. 19 (2017) 996–1004.
[29] M. Sajid, X. Zhao, D. Liu, Green Chem. 20 (2018) 5427–5453.
[30] Z. Zhang, K. Deng, ACS Catal. 5 (2015) 6529–6544.
[31] G. Yi, S.P. Teong, Y. Zhang, Green Chem. 18 (2016) 979–983.
[32] Z. Gao, R. Xie, G. Fan, L. Yang, F. Li, ACS Sustain. Chem. Eng. 5 (2017) 5852–5861.
[33] Y.B. Wang, K. Yu, D. Lei, W. Si, Y.J. Feng, L.-L. Lou, S.X. Liu, ACS Sustain. Chem.
Eng. 4 (2016) 4752–4761.
[34] X. Wan, C. Zhou, J. Chen, W. Deng, Q. Zhang, Y. Yang, Y. Wang, ACS Catal. 4
(2014) 2175–2185.
[35] H. Choudhary, K. Ebitani, Chem. Lett. 45 (2016) 613–615.
[36] X.W. Han, C.Q. Li, Y. Guo, X.H. Liu, Y.G. Zhang, Y.Q. Wang, Appl. Catal. A Gen.
526 (2016) 1–8.
Declaration of Competing Interest
[37] X.W. Han, L. Geng, Y. Guo, R. Jia, X.H. Liu, Y.G. Zhang, Y.Q. Wang, Green Chem.
18 (2016) 1597–1604.
[38] C.P. Ferraz, M. Zielinski, M. Pietrowski, S. Heyte, F. Dumeignil, L.M. Rossi,
R. Wojcieszak, ACS Sustain. Chem. Eng. 6 (2018) 16332–16340.
[39] Y. Zhou, Z.P. Ma, J.J. Tang, N. Yan, Y. Du, S. Xi, J. Wang, Nature Comm. 9 (2018)
2931.
The authors declare that they have no known competing financial
interests or personal relationships that could have appeared to influence
the work reported in this paper.
[40] Q. Zhang, J. Yu, A. Corma, Adv. Mater. (2020), 2002927.
[41] R. Ryoo, J. Kim, C. Jo, S.W. Han, J.C. Kim, H. Park, J. Han, H.S. Shin, J.W. Shin,
Nature 585 (2020) 221–224.
Acknowledgments
[42] K. Lu, J. Huang, L. Ren, C. Li, Y.J. Guan, B.W. Hu, H. Xu, J.G. Jiang, Y.H. Ma,
P. Wu, Angew. Chem. Int. Ed. 59 (2020) 6258–6262.
We highly thank the National Natural Science Foundation of China
(Nos. 22072065, U1662107, and 21476109), Six talent peaks project in
Jiangsu Province (JNHB-035), Natural Science Foundation of Jiangsu
Province (BK20200688), China Postdoctoral Science Foundation
(2020M681572), and the Project of Priority Academic Program Devel-
opment of Jiangsu Higher Education Institutions (PAPD).
[43] S.J. Datta, C. Khumnoon, Z.H. Lee, W.K. Moon, S. Docao, T.H. Nguyen, I.C. Hwang,
D. Moon, P. Oleynikov, O. Terasaki, K.B. Yoon, Science 350 (2015) 302–306.
[44] J. Liang, Z.B. Liang, R.Q. Zou, Y.L. Zhao, Adv. Mater. 29 (2017), 1701139.
[45] J. Cai, H. Ma, J.J. Zhang, Q. Song, Z.T. Du, Y.Z. Huang, J. Xu, Chem. A Eur. J. 19
(2013) 14215–14223.
[46] W.X. Zhuang, X.L. Liu, L. Chen, P.W. Liu, H.M. Wen, Y. Zhou, J. Wang, Green
Chem. 22 (2020) 4199–4209.
[47] J. Gu, Y.H. Jin, Y. Zhou, M. Zhang, Y.J. Wu, J. Wang, J. Mater. Chem. A 1 (2013)
2453–2460.
Appendix A. Supplementary data
[48] Y.J. Wu, J. Wang, P. Liu, W. Zhang, J. Gu, X.J. Wang, J. Am. Chem. Soc. 132 (2010)
17989–17991.
[49] Y. Zhou, Y.H. Jin, M. Wang, W. Zhang, J. Xie, J. Gu, L. Peng, Chem. A Eur. J. 21
(2015) 15412–15420.
Supplementary data associated with this article can be found, in the
online version, at https://doi.org/10.1016/j.apcata.2021.118106.
[50] C. Hammond, N. Dimitratos, J.A. Lopez-Sanchez, R.L. Jenkins, G. Whiting, S.
A. Kondrat, M.H. Rahim, M. Forde, A. Thetford, H. Hagen, E. Stangland, J.
A. Moulijn, S.H. Taylor, D. Willock, G.J. Hutchings, ACS Catal. 3 (2013)
1835–1844.
References
[51] Y. Li, S.Y. Huang, Z.Z. Cheng, K. Cai, L.D. Li, E. Milan, J. Lv, Y. Wang, Q. Sun, X.
B. Ma, Appl. Catal. B 256 (2019), 117777.
[1] W. Schutyser, T. Renders, S. Van den Bosch, S.-F. Koelewijn, G.T. Beckham, B.
F. Sels, Chem. Soc. Rev. 47 (2018) 852–908.
[52] H.M. Wen, J.Y. Xie, Y. Zhou, Y. Zhou, J. Wang, Catal. Sci. Technol. 9 (2019)
5725–5735.
´
´
´
[2] L.T. Mika, E. Csefalvay, A. Nemeth, Chem. Rev. 118 (2017) 505–613.
[3] Q. Wang, X.C. Ling, T.T. Ye, Y. Zhou, J. Wang, J. Mater. Chem. A 7 (2019)
19140–19151.
[53] L. Wang, S.C. Zhu, M.K. Shen, H.W. Tian, S.H. Xie, H.B. Zhang, Y.H. Zhang,
Y. Tang, Angew. Chem. Int. Ed. 56 (2017) 11764–11768.
[54] Database of Zeolite Structures, http://www.iza-structure.org/databases/.
[55] I. Kinski, P. Daniels, C. Deroche, B. Marler, H. Gies, Microporous Mesoporous
Mater. 56 (2002) 11–25.
¨
[4] S. Song, J. Zhang, G. Gozaydın, N. Yan, Angew. Chem. Int. Ed. 15 (2019)
4934–4937.
[5] H. Chen, J.S. Shen, K.Q. Chen, Y. Qin, X.Y. Lu, P.K. Ouyang, J. Fu, Appl. Catal. A
Gen. 555 (2018) 98–107.
ˇ
ˇ
ˇ
[56] M. Kasunic, J. Legisa, A. Meden, N.Z. Logar, A.M. Beale, A. Golobic, Microporous
[6] Q. Sun, S. Wang, B. Aguila, X. Meng, S. Ma, F.-S. Xiao, Nature Comm. 9 (2018)
3236–3243.
Mesoporous Mater. 122 (2009) 255–263.
[57] Y.T. Meng, H.C. Genuino, C.-H. Kuo, H. Huang, S.-Y. Chen, L.C. Zhang, A. Rossi, S.
L. Suib, J. Am. Chem. Soc. 135 (2013) 8594–8605.
[7] X. Kong, Y. Zhu, Z. Fang, J.A. Kozinski, I.S. Butler, L. Xu, X. Wei, Green Chem. 20
(2018) 3657–3682.
[58] T. Otto, S.I. Zones, E. Iglesia, J. Catal. 339 (2016) 195–208.
[59] J. Zhang, H. Wang, L. Wang, S. Ali, C.T. Wang, L.X. Wang, X.J. Meng, B. Li, D.S. Su,
F.-S. Xiao, J. Am. Chem. Soc. 141 (2019) 2975–2983.
[8] F.A. Kucherov, L.V. Romashov, K.I. Galkin, V.P. Ananikov, ACS Sustain. Chem.
Eng. 6 (2018) 8064–8092.
[9] D. Bonincontro, A. Lolli, A. Storione, A. Gasparotto, B. Berti, S. Zacchini,
N. Dimitratos, S. Albonetti, Appl. Catal. A Gen. (2019), 117279.
8

L. Chen et al.
Applied Catalysis A, General 616 (2021) 118106
[60] Z. Gao, R.F. Xie, G.L. Fan, L. Yang, F. Li, ACS Sustain. Chem. Eng. 5 (2017)
5852–5861.
[63] W. Naim, O.R. Schade, E. Saraci, D. Wüst, A. Kruse, J.-D. Grunwaldt, ACS Sustain.
Chem. Eng. 8 (2020) 11512–11521.
[61] M. Ventura, F. Nocito, E. de Giglio, S. Cometa, A. Altomare, A. Dibenedetto, Green
Chem. 20 (2018) 3921–3926.
[64] Y.Y. Gorbanev, S. Kegnæs, A. Riisager, Catal. Lett. 141 (2011) 1752–1760.
[65] N.K. Gupta, S. Nishimura, A. Takagaki, K. Ebitani, Green Chem. 13 (2011)
824–827.
[62] D.Y. Zhao, D. Rodriguez-Padron, K.S. Triantafyllidis, Y.T. Wang, R. Luque, C. Len,
ACS Sustain. Chem. Eng. 8 (2020) 3091–3102.
9