Facile synthesis of Cu3(BTC)2/cellulose acetate mixed matrix membranes and their catalytic applications in continuous flow process

Article abstract of DOI:10.1039/c7nj00672a

Metal-organic framework (MOF)-based mixed matrix membranes (MMMs) were fabricated by a combination of Cu₃(BTC)₂ MOF and polymer cellulose acetate. The cellulose acetate in the MMMs served as the matrix and the Cu₃(BTC)₂ MOF as the filler. The as-synthesized MMMs were utilized as a heterogeneous catalyst for aldehyde acetalization. The characterization techniques indicated that the Cu₃(BTC)₂ crystals were uniformly dispersed in the MMMs. The BET surface area of the Cu₃(BTC)₂-based MMM was measured to be 459 m² g^-1 at 60 wt% Cu₃(BTC)₂ loading. Furthermore, the MMMs served as an excellent catalyst under our continuous flow catalytic reaction conditions. The optimal catalytic result of benzaldehyde yield reached 94% with 60 wt% Cu₃(BTC)₂ loading of the MMMs at room temperature and the benzaldehyde diethyl acetal reached 0.59 mmol min^-1 g_Cu-BTC^-1.

Full text of DOI:10.1039/c7nj00672a

NJC
View Article Online
View Journal
PAPER
Facile synthesis of Cu3(BTC)2/cellulose acetate
mixed matrix membranes and their catalytic
applications in continuous flow process†
a
Cite this:DOI: 10.1039/c7nj00672a
Junying Hou,
Yunfeng Lu*b
Yi Luan,a Xiubing Huang,a Hongyi Gao,a Mu Yanga and
Metal–organic framework (MOF)-based mixed matrix membranes (MMMs) were fabricated by a combination
of Cu3(BTC)2 MOF and polymer cellulose acetate. The cellulose acetate in the MMMs served as the matrix
and the Cu3(BTC)2 MOF as the filler. The as-synthesized MMMs were utilized as a heterogeneous catalyst for
aldehyde acetalization. The characterization techniques indicated that the Cu3(BTC)2 crystals were uniformly
dispersed in the MMMs. The BET surface area of the Cu3(BTC)2-based MMM was measured to be 459 m2 gÀ1
at 60 wt% Cu3(BTC)2 loading. Furthermore, the MMMs served as an excellent catalyst under our continuous
flow catalytic reaction conditions. The optimal catalytic result of benzaldehyde yield reached 94% with
60 wt% Cu3(BTC)2 loading of the MMMs at room temperature and the benzaldehyde diethyl acetal reached
Received 26th February 2017,
Accepted 22nd May 2017
DOI: 10.1039/c7nj00672a
À1
À1
rsc.li/njc
0.59 mmol min
g
.
Cu-BTC
Polymer-based membranes have been widely used in con-
tinuous flow systems.15 Although the membranes have high
Introduction
The acetalization of aldehydes with alcohol or diols is a highly fluxes, they generally suffer from short life-time, low stability
practical reaction, which has been widely used to protect the and low selectivity.16 MMMs were proposed by introducing various
carbonyl group of aldehydes or ketones by forming the acetals.1 inorganic or organic fillers to the polymer matrix, which overcome
The reaction can be performed with a variety of homogeneous the drawbacks of using polymer-based membranes.17 MOFs are
acid catalysts such as HCl,2 H2SO43 and p-toluenesulfonic acid,4 increasingly being recognized as promising materials due to their
etc. However, the homogeneous catalysts suffer from some large surface area, high porosity and tunable structures.18–20
drawbacks like tedious purification process, acidic wastes and Recently, incorporating the MOFs into a polymer matrix to
environmental pollution.5 Recently, different types of hetero- fabricate MOF-based MMMs has been investigated for various
geneous catalysts such as montmorillonite,6 Envirocat EPZG7 purposes,21,22 such as gas separation,23 organic solvent nano-
and sulphated zirconia8 have been used for acetalization filtration24 and other potential applications.25
reactions. From the industrial and environmental perspectives,
Various methods have emerged that integrate MOFs with
it would be ideal to utilize heterogeneous acid catalysts, basic binders for the synthesis of MMMs, and the MOF com-
which are less corrosive, easily separated from products and ponents are responsible for the newly introduced functions.26
recyclable.9–11 To date, heterogeneous catalysts have been Most research about MOF-based MMMs focused on their utiliza-
widely used in batch vessels.12 However, the continuous flow tion in gas separations,27 liquid-phase separations or extractions.28
system has special advantages over the conventional hetero- For example, Zornoza et al. prepared the nZIF-11- and ZIF-11-based
geneous batch vessels in saving time and energy.13 Moreover, MMMs for H2/CO2 separation.29 Cohen et al. described a series of
due to the outflow of the products, overreactions in continuous MOF-based MMMs for aqueous dye sequestration.30 Wee et al.
flow systems can be avoided.14
synthesized a PDMS membrane for separating ethanol from
water.31 Said et al. reported multi-walled carbon nanotubes
incorporated in MIL-100(Fe) for water adsorption.32 However,
the MMMs have been rarely reported for catalytic application
under the continuous flow condition.33 Zhang et al. synthesized
an anodized aluminium oxide (AAO) membrane for Knoevenagel
condensation reaction.34
a Beijing Key Laboratory of Function Materials for Molecule & Structure
Construction, School of Materials Science and Engineering, University of Science
and Technology Beijing, Beijing 100083, P. R. China
b Department of Materials Science and Engineering, University of California,
Los Angeles, CA 90034, USA. E-mail: luucla@ucla.edu; Tel: +1 310-794-7238
† Electronic supplementary information (ESI) available: Optical photographs,
SEM, XRD, FT-IR, BET of catalyst. See DOI: 10.1039/c7nj00672a
Among the MOFs reported in literature, Cu3(BTC)2 (BTC =
%
1,3,5-benzenetricarboxylate) possesses the cubic structure Fm3m
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2017
New J. Chem.

View Article Online
Paper
NJC
with the window diameter of 0.9 nm.35,36 Due the advantage of 2.4. Continuous flow system and catalytic tests
their porous structure, Cu3(BTC)2-based MMM catalysts with
System set-up. For our continuous flow experiments, a
system was designed according to the previously described
report.38 Briefly, the experiments have three different configu-
rations, including two injection pumps and one injection
syringe with MMMs as the self-supported catalyst. First, the
MOF-based mixed matrix membrane was immobilized on the
bottom of the injection syringe, and then the aldehyde sub-
strate and absolute ethanol were injected into the column using
two injection pumps (Fig. S1, ESI†). Finally, the products after
the reaction were collected by a collecting flask and analyzed by
GC-MS.
various Cu3(BTC)2 loading amounts were prepared via a simple
solvent evaporation preparation method. The Lewis acidic copper
centres are well distributed in the porous structure of Cu3(BTC)2,
and the voids in MOF offer the channel structure for substrates,
which improve the selectivity of the membranes. Furthermore, the
catalytic efficiency of our synthesized Cu3(BTC)2-based MMM
catalysts was evaluated with benzaldehyde acetalization. The
reaction occurs at room temperature and atmospheric pressure
with 94% yield of benzaldehyde diethyl acetal in our continuous
flow system. The system can produce acetals under continuous flow
conditions, and the reactor allows the processing of products in
sequence without any decrease in catalytic activity within 24 hours.
3. Results and discussion
3.1. Characterization of the Cu3(BTC)2-based mixed matrix
membranes
2. Experimental
2.1 Materials
The morphology and the cross-section of the CA membrane and
the Cu3(BTC)2-0.6 MMM were characterized by SEM, as shown
in Fig. 1. As can be seen, the CA membrane is crack-free and
easily folded (Fig. 1a and Fig. S2, ESI†). It can be observed that
the fibers are twisted in the CA membrane (Fig. 1b). The size of
synthesized Cu3(BTC)2 particles is around 15–20 mm (Fig. 1c),
and the MOF component is uniformly distributed on the CA
membrane (Fig. 1d), which is critical for the uniform growth of
MMMs.39 As the Cu3(BTC)2 loading increased, more significant
aggregation of crystals was observed on the polymer (Fig. S3,
ESI†). SEM images of the Cu3(BTC)2-0.4 MMM, the Cu3(BTC)2-
0.5 MMM and the Cu3(BTC)2-0.6 MMM clearly showed that the
Cu3(BTC)2 crystals were well-dispersed in the CA membrane at
a various loading wt% (40–60%, w/w).
Cupric nitrate trihydrate (Cu(NO3)2Á3H2O) and cellulose acetate
(CA, average Mn = 30 000 with acetyl content of 39.8 wt%) were
supplied by Beijing Chemical Reagent Company. Moreover,
1,3,5-benzenetricarboxylic acid (C9H6O6) was purchased from
Alfa Aesar. All reagents were used without further purification.
2.2 Catalyst preparation
Preparation of the Cu3(BTC)2-based mixed matrix membranes.
Cu3(BTC)2 crystals were synthesized according to the previous
report.37 Typically, 1.87 g cellulose acetate (CA) was dissolved in
acetone (25 g) at room temperature for 12 h. Moreover, 0.05 g
Cu3(BTC)2 was dispersed in acetone, and then 10 g, 6.68 g, and
4.45 g of CA solution were added to the solution by stirring for
12 h. After the solution was degassed, it was cast uniformly onto
the glass substrate, and then the Cu3(BTC)2-based MMMs were
formed by solvent evaporation (Scheme S1, ESI†). Finally, the
membranes were peeled off from the glass substrate and dried for
24 h. The samples were named Cu3(BTC)2-x MMM, in which x is
the initial loading proportion of Cu3(BTC)2 on MMMs.
The crystalline structures of the synthesized CA membrane,
the Cu3(BTC)2, the Cu3(BTC)2-0.4 MMM, the Cu3(BTC)2-0.5 MMM
2.3. Characterization
The morphology and the structure of the MMMs were charac-
terized by scanning electron microscopy (SEM, ZEISS SUPRA55).
The phase composition was investigated by X-ray diffraction
(XRD, M21X, Cu Ka radiation, l = 0.154178 nm). Fourier
transform infrared spectra (FT-IR) were analyzed by a Nicolet
6700 spectrometer. The thermal decomposition behavior of the
MMMs was measured by thermogravimetric (TG) analysis using
a Netzsch STA449F3 instrument from room temperature to
800 1C at a rate of 10 1C minÀ1 under nitrogen flow. The BET
surface area and pore volume of MMMs were investigated by
nitrogen sorption–desorption isotherms at 77 K using an
AUTOSORB-1C analyzer. The products were measured by gas
chromatography-mass spectroscopy (GC-MS, Agilent 7890/5975C-
GC/MSD); nitrobenzene was used as the internal standard, the
HP-5MS column was used in the GC, and helium was used as
the carrier gas.
Fig. 1 SEM images of the CA membrane (a), the cross-section of CA
membrane (b), the Cu3(BTC)2 (c) and the Cu3(BTC)2-0.6 MMM ((d) the
circles are Cu-BTC).
New J. Chem.
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2017

View Article Online
NJC
Paper
peaks from 2700–3600 cmÀ1 can be ascribed to the stretching
modes of the absorbed water molecules in the samples.44 The
band at 2952 cmÀ1 is attributed to the vibration of the C–H
bond.45 The bands at 1750 cmÀ1 and 1643 cmÀ1 are CQO
stretching of the carboxylate group.46,47 Moreover, the bands at
1233 cmÀ1 and 1040 cmÀ1 correspond to the C–O stretching
mode of the ether linkage.48,49 The band at 906 cmÀ1 is
assigned to the stretching vibration of the C–O bond in the
amorphous region,50 whereas 603 cmÀ1 is the structural factor
(Fig. 3a).51 The 1443 and 1375 cmÀ1 peaks are attributed to the
symmetric stretch of the carboxylate group.52 The shift of the
carboxylate group was affected by connecting a group of
the carboxylate group in the CA membrane and the Cu-BTC.53
The band at 938 cmÀ1 is the bending mode of the C–H out-of-
plane, whereas the out-of-plane bending modes of the C–C ring
Fig. 2 XRD patterns of the CA membrane (a), the Cu3(BTC)2 (b), the
Cu3(BTC)2-0.6 MMM (c), and the Cu3(BTC)2-0.6 MMM after reaction (d).
are observed at 728 cm ,
À1 54 and the band at 488 cmÀ1 represents
the vibrational mode of the copper center (Fig. 3b).55 All spectra of
MMMs were similar when the Cu3(BTC)2 was dispersed on the CA
membrane (Fig. 3c and Fig. S4, ESI†). The additional bands in
Cu-BTC MMMs are consistent with the CA membrane (Fig. 3c and
Fig. S5, ESI†). The FT-IR results suggested that both the Cu3(BTC)2
and the CA component are in the MMM composite.
and the Cu3(BTC)2-0.6 MMM were characterized by X-ray diffrac-
tion (XRD). The peaks at 2y = 8.41 and 21.71 originated from the
typical structure of cellulose I (Fig. 2a).40 The XRD pattern of our
as-synthesized Cu3(BTC)2 is in line with that of the reported
Cu3(BTC)2 (Fig. 2b).41 In addition, Cu3(BTC)2-based MMMs with
different MOF loadings have similar crystalline structures (Fig. 2c
and Fig. S4, ESI†). The presence of sharp peaks confirmed that
the structure of Cu3(BTC)2 was intact. However, some wide
diffraction peaks of the MMMs were observed, possibly due to
the presence of polymer.42 The patterns of the Cu3(BTC)2-based
MMMs suggested that the mixture of the MOF component and
the polymer membrane leads to the formation of Cu3(BTC)2
MMMs. In Fig. 2d, there was only one peak appearing at 14.71,
which was assigned to the (331) crystal plane.43 It indicated that
the water molecule connected with Cu2+ carboxylates in Cu-BTC
was removed during the catalysis.
The thermal decomposition behaviors of samples were
further investigated with thermogravimetric analysis (TGA).
The TG curves of the membranes showed that there were two
weight loss steps from 50 to 800 1C (Fig. 4). The weight loss at a
temperature before 300 1C is attributed to the evaporation of
moisture, whereas the weight loss between 300 and 370 1C is
attributed to degradation of the organic group (Fig. 4, black).56
The decomposition of the Cu3(BTC)2 starts at around 220 1C,
and the slow mass loss at 310 1C is assigned to the decomposition
of coordination water molecules and organic ligands (Fig. 4,
red).57 The MMMs with 40, 50, and 60 wt% Cu3(BTC)2 show two
major weight degradation steps, and the decomposition of the
Cu3(BTC)2-based MMMs occurs at about 280 1C, which shows a
higher thermal resistance compared to that of the pure Cu3(BTC)2
in the presence of the CA membrane. Importantly, the MMMs
showed increased thermal stability, which can be attributed to the
The FT-IR spectra of the synthesized CA membrane, the
Cu3(BTC)2, the Cu3(BTC)2-0.4 MMM, the Cu3(BTC)2-0.5 MMM
and the Cu3(BTC)2-0.6 MMM are shown in Fig. 3. The broad
Fig. 3 FT-IR spectra of the CA membrane (a), the Cu3(BTC)2 (b) and the
Fig. 4 TG curves of the Cu3(BTC)2, the Cu3(BTC)2-0.4 MMM, the
Cu3(BTC)2-0.6 MMM (c).
Cu3(BTC)2-0.5 MMM and the Cu3(BTC)2-0.6 MMM.
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2017
New J. Chem.

View Article Online
Paper
NJC
Cu3(BTC)2-0.6 MMM. It was placed in an injection syringe, and
the solution of reactants (benzaldehyde and absolute ethanol)
was passed through the two injection pumps with flow rates of
3.2 mL minÀ1 and 0.1 mL minÀ1, respectively. The benzaldehyde
diethyl acetal was produced constantly, and the product solution
was monitored by GC-MS. Fig. 6 shows that the conversion
reaches 94% with 99% selectivity after 2 h oÀn1 flow, and the
productivity reaches 0.59 mmol minÀ1 gCu-BTC at the steady
state, and the yield is maintained at 94% in 24 hours. With the
increase of the flow rate (benzaldehyde), the yields of benzaldehyde
diethyl acetal increased. The conversion of benzaldehyde was found
to be 79%, 87% and 94% for the flow rates at 0.8 mL minÀ1
,
1.6 mL minÀ1, and 3.2 mL minÀ1, respectively (Fig. S8, ESI†). Our
system achieved a continuous production of benzaldehyde diethyl
acetal using the Cu3(BTC)2-0.6 MMM under mild conditions.
No conversion of benzaldehyde was observed when the CA
membrane was utilized as the catalyst. In the meantime, the
Cu-BTC-0.6 MMM gave 94% conversion of benzaldehyde and
99% selectivity of benzaldehyde diethyl acetal (Table 2, entries
1 and 2). It can be concluded that the Cu3(BTC)2 was respon-
sible for the acetalization of benzaldehyde. The conversion
reaches 78% with 99% selectivity and 99% conversion with
82% selectivity using methanol and ethylene glycol, respectively
(Table 2, entries 3 and 4). The compromised selectivity of
benzaldehyde ethylene glycol acetal was due to the formation
of by-products.59 The Cu3(BTC)2 catalyst shows quite low cata-
lytic activity (Table 4, entry 5). The thermodynamic limitations
in acetalization reaction result in low yield of the products.
Fig. 5 N2 adsorption–desorption isotherms of the Cu3(BTC)2-0.6 MMM.
interaction between cellulose acetate and the MOF.58 The TG
curves show that the weight losses of Cu3(BTC)2 mixed matrix
membranes are 34%, 48%, and 61% (Fig. 4, blue, dark cyan and
cyan, respectively). Comparatively, Cu3(BTC)2 MMMs show higher
thermal resistance than that of the pure Cu3(BTC)2 but lower than
that of the CA membrane. In addition, the Cu3(BTC)2-0.6 MMM
after reaction showed a mass loss of 5% up to the temperature of
220 1C. The weight change confirmed that the water molecule of
the Cu3(BTC)2 structure had been removed (Fig. S5, ESI†).43
The surface area and porosity of the synthesized CA membrane,
the Cu3(BTC)2, the Cu3(BTC)2-0.4 MMM, the Cu3(BTC)2-0.5 MMM
and the Cu3(BTC)2-0.6 MMM were evaluated by the N2 adsorption–
desorption isotherms (Fig. 5 and Fig. S6, ESI†), and the data are
summarized in Table 1.
The results indicated that the BET surface areas and the total
pore volumes of Cu3(BTC)2-x MMM increased as the loading of the
Cu3(BTC)2 increased. The pore size distribution of Cu-BTC-0.6
MMM was calculated using nitrogen adsorption isotherm, following
the method of BJH (Barrett, Joyner and Halenda). The average pore
size of Cu-BTC-0.6 MMM is about 1.64 nm, and there are no nano-
pores in the CA membrane (Fig. 5 and Table 1). The results show that
the existence of nanopores in the Cu3(BTC)2 membrane is related to
the formation of Cu3(BTC)2 MOF inside the CA membrane.
Fig. 6 Acetalization of benzaldehyde with ethanol as a function of time
on the Cu3(BTC)2-0.6 MMM. Triangle: Conversion. Square: Selectivity.
3.2. Catalytic activity and flow reaction system using the
Cu3(BTC)2-based mixed matrix membranes as catalyst
The optimization studies of the acetalization reaction under
continuous flow condition were carried out using as-synthesized
Table 2 The catalytic activity for acetalization of benzaldehyde using
different catalysta
Table 1 Nitrogen adsorption–desorption data for CA membrane, Cu3(BTC)2,
Cu3(BTC)2-0.4 MMM, Cu3(BTC)2-0.5 MMM and Cu3(BTC)2-0.6 MMM
Entry Catalyst
Alcohol
EtOH
Conv.b (%) Sel.b (%)
1
2
3
4
5
CA membrane
Cu-BTC-0.6 MMM EtOH
Cu-BTC-0.6 MMM MeOH
Cu-BTC-0.6 MMM Ethylene glycol
o5
94
78
99
16
0
99
99
82
99
Samples
SBET (m2 gÀ1
)
Vp (cm3 gÀ1
)
CA membrane
Cu3(BTC)2
Cu3(BTC)2-0.4 MMM
Cu3(BTC)2-0.5 MMM
Cu3(BTC)2-0.6 MMM
2.8
1447
137
225
459
—
c
0.56
0.08
0.13
0.18
Cu3(BTC)2
EtOH
a
Reaction conditions: Cu3(BTC)2 mixed matrix membrane catalyst,
b
benzaldehyde (3.2 mL minÀ1) and alcohol (0.1 mL minÀ1), 24 h.
Determined by GC-MS using nitrobenzene as the internal standard.
c
SBET: BET surface area; Vp: total pore volume.
0.05 g Cu3(BTC)2.
New J. Chem.
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2017

View Article Online
NJC
Paper
Table 4 Size and shape selectivity in acetalization of aldehydea
Conv.b (%) Sel.b (%)
The continuous removal of water from the acetalization reaction
through the Cu3(BTC)2 membrane promoted the reaction to the
product side, thus increasing the yield of acetals.60 Therefore, the
optimal acetalization reaction of benzaldehyde with ethanol was
obtained at room temperature and atmospheric pressure using
the Cu-BTC-0.6 MMM at a flow rate of benzaldehyde and ethanol
of 3.2 mL minÀ1 and 0.1 mL minÀ1, respectively, under the
24 hours of reaction time.
With the optimal reaction conditions, various aromatic,
aliphatic aldehydes and ketones were further evaluated using
ethanol as the nucleophile. The catalytic results are summarized in
Table 3. Benzaldehyde was converted to its benzaldehyde diethyl
acetal with 94% conversion and 99% selectivity (Table 3, entry 1).
Electron-rich benzylic aldehyde, such as p-methoxybenzaldehyde
gave low yields (Table 3, entries 2). As expected, the 4-fluoro-
benzaldehyde gave 87% conversion and 99% selectivity of the
desired 1-(diethoxymethyl)-4-fluorobenzene. Furthermore, acetali-
zation of phenylacrolein resulted in 82% conversion and 99%
selectivity without the interference of the CQC double bond
Entry Substrate
Molecular size
1
94
56
18
99
99
99
2
3
a
Reaction conditions: Cu3(BTC)2 mixed matrix membrane catalyst,
(Table 3, entry 4). Furfuraldehyde was tested as a heteroaromatic benzaldehyde (3.2 mL minÀ1) and alcohol (0.1 mL minÀ1), 24 h.
b
Determined by GC-MS using nitrobenzene as the internal standard.
aldehyde, which provided a good yield of the corresponding
2-(diethoxymethyl)furan (Table 3, entry 5). Moreover, 1-octanal
provided a 74% conversion with high selectivity towards the
formation of the important 1,1-diethoxyoctane (Table 3, entry 6).
Moreover, ketone substrate was not compatible with our flow
system, and low activity was observed using ethanol as the nucleo-
phile (Table 3, entry 7).
For the catalytic applications, the well-defined MOF pores
may offer shape- and size-selective catalysis. The shape and the
size selectivity of our synthesized Cu-BTC-0.6 MMM were
investigated in acetalization of aldehyde, as shown in Table 4.
The increase in the size of aromatic rings resulted in decreased
yields of the corresponding acetals.
Because the molecular size of benzaldehyde (0.53 nm and
0.66 nm) is much smaller than the pore size of Cu-BTC-0.6
MMM, the yield could reach up to 94%. By increasing the
number of aromatic rings, 2-naphthaldehyde with a molecular
size of 0.77 nm and 0.66 nm gave a lower yield under the same
conditions. In addition, the 9-anthraldehyde with the biggest
molecular size of 1.03 nm and 0.66 nm gave the lowest yield.
Table
3
Acetalization of various aldehydes with ethanol using the
Cu3(BTC)2-0.6 mixed matrix membrane as catalysta
Entry Substrate
1
Product
Conv.b (%) Sel.b (%)
94
68
99
99
2
4. Conclusions
3
4
87
82
99
99
In summary, the Cu3(BTC)2-based MMMs were successfully pre-
pared by introducing different loading of the Cu3(BTC)2 crystals
inside the cellulose acetate membrane. The resulting composites
were efficient for acetalization of aldehydes in a continuous flow
system. We confirmed that the flow is steady, and the desired
continuous catalytic production was achieved. The results demon-
strated that the MOF-based MMM catalyst with 60 wt% Cu3(BTC)2
loading was the optimal mixed matrix membrane for the
continuous flow catalysis, and the productivity can reach
0.59 mmol minÀ1 gCu-BTCÀ1. Furthermore, the yield of the
Cu-BTC-0.6 MMM catalyst can be maintained at 94% after 24 hours.
5
6
89
74
99
99
7
5
99
Acknowledgements
a
Reaction conditions: aldehyde (3.2 mL minÀ1 l), ethanol (0.1 mL minÀ1),
b
We thank the National Key Research and Development Program
of China (No. 2016YFB0701100) and the Fundamental Research
Cu3(BTC)2 mixed matrix membrane catalyst, 24 h. Determined by GC-MS
using nitrobenzene as the internal standard.
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2017
New J. Chem.

View Article Online
Paper
NJC
24 J. Campbell, G. Szekely, R. P. Davies, D. C. Braddock and
A. G. Livingston, J. Mater. Chem. A, 2014, 2, 9260–9271.
25 B. Zornoza, C. Tellez, J. Coronas, J. Gascon and F. Kapteijn,
Microporous Mesoporous Mater., 2013, 166, 67–78.
26 S. Z. Li and F. W. Huo, Nanoscale, 2015, 7, 7482–7501.
27 C. Casado-Coterillo, A. Fernandez-Barquin, B. Zornoza, C. Tellez,
J. Coronas and A. Irabien, RSC Adv., 2015, 5, 102350–102361.
28 O. de la Iglesia, S. Sorribas, E. Almendro, B. Zornoza,
C. Tellez and J. Coronas, Renewable Energy, 2016, 88, 12–19.
29 J. Sanchez-Lainez, B. Zornoza, C. Tellez and J. Coronas,
J. Mater. Chem. A, 2016, 4, 14334–14341.
30 M. S. Denny and S. M. Cohen, Angew. Chem., Int. Ed., 2015,
54, 9029–9032.
31 P. V. Naik, L. H. Wee, M. Meledina, S. Turner, Y. Li, G. V.
Tendeloo, J. A. Martens and I. F. J. Vankelecom, J. Mater.
Chem. A, 2016, 4, 12790–12798.
Funds for the Central Universities (FRF-BD-16-008A) for financial
support.
Notes and references
1 G. Sartori, R. Ballini, F. Bigi, G. Bosica, R. Maggi and
P. Righi, Chem. Rev., 2004, 104, 199–250.
2 M. B. Guemez, J. Requies, I. Agirre, P. L. Arias, V. L. Barrio
and J. F. Cambra, React. Funct. Polym., 1997, 3, 53–65.
3 F. Frusteri, L. Spadaro, C. Beatrice and C. Guido, Chem. Eng.
Sci., 2007, 134, 239–245.
4 M. B. Guemez, J. Requies, I. Agirre, P. L. Arias, V. L. Barrio
and J. F. Cambra, Chem. Eng. J., 2013, 228, 300–307.
5 M. X. Tan, L. Q. Gu, N. N. Li, J. Y. Ying and Y. G. Zhang,
Green Chem., 2013, 15, 1127–1132.
32 N. U. Qadir, S. A. M. Said, R. B. Mansour, K. Mezghani and
A. UI-Hamid, Dalton Trans., 2016, 45, 15621–15633.
33 E. Gkaniatsou, C. Sicard, R. Ricoux, J. P. Mahy, N. Steunou
and C. Serre, Mater. Horiz., 2017, 4, 55–63.
34 Y. F. Yu, X. J. Wu, M. T. Zhao, Q. L. Ma, J. Z. Chen, B. Chen,
M. Sindoro, J. Yang, S. K. Han, Q. P. Lu and H. Zhang,
Angew. Chem., Int. Ed., 2017, 56, 578–581.
6 Y. Masui, J. C. Wang, K. Teramura, T. Kogure, T. Tanaka and
M. Onaka, Microporous Mesoporous Mater., 2014, 198,
129–138.
7 B. P. Bandgar, M. M. Kulkarni and P. P. Wasgaonkar, Synth.
Commun., 1997, 27, 627–634.
8 P. Sudarsanam, B. Mallesham, A. N. Prasad, P. S. Reddy and
B. M. Reddy, Fuel Process. Technol., 2013, 106, 539–545.
9 Y. Leng, J. W. Zhao, P. P. Jiang and D. Lu, Catal. Sci.
Technol., 2016, 6, 875–881.
35 V. K. Peterson, Y. Liu, C. M. Brown and C. J. Kepert, J. Am.
Chem. Soc., 2006, 128, 15578–15579.
36 S. L. James, Chem. Soc. Rev., 2003, 32, 276–288.
37 K. Schlichte, T. Kratzke and S. Kaskel, Microporous Mesoporous
Mater., 2004, 73, 81–88.
38 C. Ayats, A. H. Henseler and M. A. Pericas, ChemSusChem,
2012, 5, 320–325.
39 M. A. Aroon, A. F. Ismail, T. Matsura and M. M. Montazer-
Rahmati, Sep. Purif. Technol., 2010, 75, 229–242.
40 A. L. Da Roz, F. L. Leite, L. V. Pereiro, P. A. P. Nascente,
V. Zucolotto, O. N. Oliveira, Jr and A. J. F. Carvalho, Carbohydr.
Polym., 2010, 80, 65–70.
10 F. C. Zheng, Q. W. Chen, L. Hu, N. Yan and X. K. Kong,
Dalton Trans., 2014, 43, 1220–1227.
11 F. M. Zhang, J. Shi, Y. Jin, Y. H. Fu, Y. J. Zhong and
W. D. Zhu, Chem. Eng. J., 2015, 259, 183–190.
12 A. M. Ruhul, M. A. Kalam, H. H. Masjuki, I. M. R. Fattah,
S. S. Reham and M. M. Rashed, RSC Adv., 2015, 5,
101023–101044.
13 T. Tsubogo, H. Oyamada and S. Kobayashi, Nature, 2015,
520, 329–332.
14 C. Wiles and P. Watts, Green Chem., 2012, 14, 38–54.
15 E. A. Feijani, H. Mandavi and A. Tavasoli, Chem. Eng. Res.
Des., 2015, 96, 87–102.
41 A. J. Graham, J. C. Tan, D. R. Allan and S. A. Moggach, Chem.
Commun., 2012, 48, 1535–1537.
42 A. F. Bushell, M. P. Attfied, C. R. Mason, P. M. Budd,
Y. Yampolskii, L. Starannikova, A. Rebrow, F. Bazzarelli,
P. Bernardo, J. C. Jansen, M. Lanc, K. Friess, V. Shantarovich,
V. Gustov and V. Isaeva, J. Membr. Sci., 2013, 427, 48–62.
43 K. Schlichte, T. Kratzke and S. Kaskel, Microporous Meso-
porous Mater., 2004, 73, 81–88.
44 H. Y. Gao, G. Wang, Y. Luan, K. Chaikittikul, X. W. Zhang,
M. Yang, W. J. Dong and Z. Shi, CrystEngComm, 2014, 16,
2520–2526.
16 S. L. Qiu, M. Xue and G. S. Zhu, Chem. Soc. Rev., 2014, 43,
6116–6140.
17 B. Seoane, J. Coronas, I. Gascon, M. E. Benavides, O. Karvan,
J. Caro, F. Kapteijn and J. Gascon, Chem. Soc. Rev., 2015, 44,
2421–2454.
18 S. Furukawa, J. Reboul, S. Diring, K. Sumida and S. Kitagawa,
Chem. Soc. Rev., 2014, 43, 5700–5734.
19 H. Furukawa, K. E. Cordova, M. O’Keeffe and O. M. Yaghi,
Science, 2013, 341, 1230444.
20 V. Colombo, S. Galli, H. J. Choi, G. D. Han, A. Maspero, 45 F. Gholamian, G. Nabiyouni, D. Ghanbari, R. Jalajerdi and
G. Palmisano, N. Masciocchi and J. R. Long, Chem. Sci.,
2011, 2, 1311–1319.
21 Z. B. Su, J. H. Chen, X. Sun, Y. H. Huang and X. F. Dong, RSC
Adv., 2015, 5, 99008–99017.
A. Aminifazl, High Temp. Mater. Processes, 2013, 32, 125–132.
46 V. A. Oliveira, T. C. Veloso, V. A. Leao, C. G. dos Santos and
V. R. Botaro, Quim. Nova, 2013, 36, 102–106.
47 Y. L. Yang, L. C. Song, C. Peng, E. H. Liu and H. B. Xie, Green
Chem., 2015, 17, 2758–2763.
22 Z. X. Kang, Y. W. Peng, Z. G. Hu, Y. H. Qian, C. L. Chi,
L. Y. Yeo, L. Tee and D. Zhao, J. Mater. Chem. A, 2015, 3, 48 C. A. Borgo, A. M. Lazarin, Y. V. Kholin, R. Landers and
20801–20810. Y. Gushikem, J. Braz. Chem. Soc., 2004, 15, 50–57.
23 G. X. Dong, H. Y. Li and V. K. Chen, J. Mater. Chem. A, 2013, 49 N. A. Razuki, A. W. Aziz, N. S. A. Satar and N. H. M. Kaus, Int.
1, 4610–4630.
J. Electroactive Mater., 2015, 3, 38–45.
New J. Chem.
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2017

View Article Online
NJC
Paper
50 H. Zhang, J. Wu, J. Zhang and J. S. He, Macromolecules, 56 K. C. Hsu, J. D. Liao, J. R. Yang and Y. S. Fu, CrystEngComm,
2005, 38, 8272–8277. 2013, 15, 4303–4308.
51 R. Delgado-Macuil, M. Rojas-Lopez, V. L. Gayou, A. Orduna- 57 V. R. A. Lucena, L. C. C. de Araujo, M. D. Rodrigues, T. G. da
Diaz and J. Diaz-Reyes, Mater. Charact., 2007, 58, 771–775.
52 N. Drenchev, E. Ivanova, M. Mihaylov and K. Hadjiivanov,
Phys. Chem. Chem. Phys., 2010, 12, 6423–6427.
Silva, V. R. A. Pereira, G. C. G. Militao, D. A. F. Fontes,
P. J. Rolim-Neto, F. F. da Silva and S. C. Nascimento,
Biomed. Pharmacother., 2013, 67, 707–713.
53 T. Noguchi, T. A. Ono and Y. Inoue, BBA, Biochim. Biophys. 58 S. Basu, A. Cano-Odena and I. F. J. Vankelecom, J. Membr.
Acta, Biomembr., 1995, 1232, 59–66. Sci., 2010, 362, 478–487.
54 J. B. DeCoste, G. W. Peterson, B. J. Schindler, K. L. Killops, M. A. 59 A. Dhakshinamoorthy, M. Alvaro and H. Garcia, Adv. Synth.
Browe and J. J. Mahle, J. Mater. Chem. A, 2013, 1, 11922–11932. Catal., 2010, 352, 3022–3030.
55 S. K. Bhardwaj, A. L. Sharma, N. Bhardwaj, M. Kukkar, A. A. S. 60 I. Agirre, M. B. Guemez, H. M. van Veen, A. Motelica,
Gill, K. H. Kim and A. Deep, Sens. Actuators, B, 2017, 240, 10–17. J. F. Vente and P. L. Arias, J. Membr. Sci., 2011, 371, 179–188.
This journal is © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2017
New J. Chem.