H5PMo10V2O40 immobilized on functionalized chloromethylated polystyrene by electrostatic interactions: A highly efficient and recyclable heterogeneous catalyst for hydroxylation of benzene

Article abstract of DOI:10.1039/c6cy01270a

H₅PMo₁₀V₂O₄₀ (PMoV₂) was immobilized on N,N-dimethylhexadecylamine functionalized chloromethylated polystyrene (DMA16-CMPS) by electrostatic interaction and used as a catalyst for the direct hydroxylation of benzene to phenol with H₂O₂. The results of FT-IR, XRD and TGA indicated that PMoV₂ was immobilized and finely dispersed on DMA16-CMPS, and the structure was well preserved. UV-vis DRS, EPR and XPS confirmed the presence of V⁴⁺ in the catalyst due to electronic interactions between PMoV₂ and DMA16-CMPS. The textural and morphological properties of the catalyst were characterized by N₂ adsorption-desorption, SEM and TEM. The hydrophobicity of the catalyst was also characterized by contact angle measurement. PMoV₂/DMA16-CMPS exhibited excellent catalytic performance with 22.1% conversion of benzene and a phenol yield of 21.9% at 65°C. The high catalytic performance of PMoV₂/DMA16-CMPS is attributed to high dispersion of PMoV₂ on mesoporous and macroporous DMA16-CMPS, good benzene adsorption and phenol desorption ability, and V⁵⁺/V⁴⁺ redox pairs in the catalyst. Meanwhile, PMoV₂/DMA16-CMPS has the advantages of facile recovery and recycling.

Full text of DOI:10.1039/c6cy01270a

View Article Online
View Journal
Catalysis
Science &
Technology
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: H. Wang, L. Fang,
Y. Yang, L. Zhang and Y. Wang, Catal. Sci. Technol., 2016, DOI: 10.1039/C6CY01270A.
This is an Accepted Manuscript, which has been through the
Royal Society of Chemistry peer review process and has been
accepted for publication.
Accepted Manuscripts are published online shortly after
acceptance, before technical editing, formatting and proof reading.
Using this free service, authors can make their results available
to the community, in citable form, before we publish the edited
article. We will replace this Accepted Manuscript with the edited
and formatted Advance Article as soon as it is available.
You can find more information about Accepted Manuscripts in the
Information for Authors.
Please note that technical editing may introduce minor changes
to the text and/or graphics, which may alter content. The journal’s
standard Terms & Conditions and the Ethical guidelines still
apply. In no event shall the Royal Society of Chemistry be held
responsible for any errors or omissions in this Accepted Manuscript
or any consequences arising from the use of any information it
contains.
www.rsc.org/catalysis

Please do not adjust margins
Catalysis Science & Technology
Page 1 of 23
View Article Online
DOI: 10.1039/C6CY01270A
Journal Name
ARTICLE
H5PMo10V2O40 immobilized on functionalized chloromethylated polystyrene
by electrostatic interactions: a highly efficient and recyclable heterogeneous
catalyst for hydroxylation of benzene
Hefang Wanga, Luping Fanga, Yongfang Yanga,*, Li Zhanga, Yanji Wanga,*
H5PMo10V2O40 (PMoV2) was immobilized on N, Nꢀdimethylhexadecylamine functionalized
chloromethylated polystyrene (DMA16ꢀCMPS) by electrostatic interaction and used as
catalyst for the direct hydroxylation of benzene to phenol with H2O2. The results of FTꢀIR,
XRD and TGA indicated that PMoV2 was immobilized and finely dispersed on DMA16ꢀ
CMPS, and the structure was well preserved. UVꢀvis DRS, EPR and XPS confirmed the
presence of V4+ in the catalyst due to electronic interactions between PMoV2 and DMA16ꢀ
CMPS. The textural and morphology property of the catalyst were characterized by N2
adsorptionꢀdesorption, SEM and TEM. The hydrophobicity of the catalyst was also
characterized by contact angle. PMoV2/DMA16ꢀCMPS exhibited excellent catalytic
performance with 22.1% conversion of benzene and 21.9% yield of phenol at 65°C. The high
catalytic performance of PMoV2/DMA16ꢀCMPS is attributed to high dispersion of PMoV2 on
mesoporous and macroporous DMA16ꢀCMPS, good benzene adsorption and phenol
desorption ability and V5+/V4+ redox pair in the catalyst. Meanwhile, PMoV2/DMA16ꢀCMPS
has the advantages of facile recovery and recycling.
Received 00th January 20xx,
Accepted 00th January 20xx
DOI: 10.1039/x0xx00000x
www.rsc.org/
which may lead to the over oxidation of benzene.6 While
using N2O as oxidant can provide high selectivity to
1 Introduction
Phenol, as an important chemical intermediate, is widely
used for the manufacture of resins, pesticides, medicine
and dyestuffs.1 Currently, phenol is mainly produced by
the threeꢀstep cumene process in industry, which suffers
from many disadvantages such as low oneꢀpass yield of
phenol, high energy consumption, low atomic efficiency
and with equimolar of acetone as byꢀproduct.2,3
Therefore, the clean process of direct hydroxylation of
benzene to phenol with O2, N2O or H2O2 has been the
focus of researches in recent years.2,4,5 However, the
conversion of benzene with O2 needs a relatively high
reaction temperature in order to activate the oxidant,
phenol, the complex operational process limits the
industrial application of the process.6,7 Instead, hydrogen
peroxide is recognized as a promising alternative for
hydroxylation of benzene because of its facilitated
handling, high availability, as well as water as byꢀ
product.8,9
Heteropolyacids (HPAs), which are a large family of
transition metal oxygen anion clusters with structural
diversity, strong Brönsted acidity, tunable redox
capability as a result of changing their compositions and
structures at the molecular level,10 have attracted great
attention for organic transformations.11,12 Vanadium
substituted HPAs were used as efficient catalysts for
hydroxylation of benzene with H2O2.13 However, high
solubility of vanadium substituted HPAs in polar solvents
especially in acetic acid medium resulted in difficulty of
catalyst recovery and reuse.
Electronic Supplementary Information (ESI) available: Calculation of carbon
balance (CB) for the oxidation of benzene using various catalysts and
catalysis mechanism.
See DOI: 10.1039/x0xx00000x
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 1
Please do not adjust margins

Please do not adjust margins
Catalysis Science & Technology
Page 2 of 23
View Article Online
DOI: 10.1039/C6CY01270A
ARTICLE
Combination HPAs with functionalized cations,8,14ꢀ20
Journal Name
PMoV2/DMA16ꢀCMPS has the advantages of facile
recovery and recycling.
direct dispersion of HPAs on supports such as silica,21,22
active carbon,23 encapsulation HPAs into the metalꢀ
organic framework MOFꢀ199,24 and binding HPAs on the
surface of support through acidꢀbase interaction, such as
amine functionalized SBAꢀ1525 and aminated monolithic
poly(divinylbenzeneꢀcoꢀvinylbenzyl chloride) copolyꢀ
mer,26 were proved to be effective methods to
heterogenize the HPAs. Nevertheless, catalysts prepared
by the above mentioned methods still suffered from
several drawbacks, such as nonhomogeneous dispersion
of HPAs and pores blocked by HPAs aggregates as well
as leaking of active sites, low catalytic activity and low
catalyst recovery rate.
2. Experimental
2.1 Materials
All solvents and reagents were analytical grade and used
as received. Benzene was purchased from Tianjin Funing
Fine Chemical Co. Ltd. 30% H2O2 aqueous solution,
acetonitrile and acetic acid were obtained from Tianjin
Bodi Chemical Co. Ltd. nꢀC16H33N(CH3)2 was purchased
from
Shanghai
Hansi
Chemical
Co.
Ltd.
Chloromethylated polystyrene (CMPS, containing 4.8
mmol Cl/g of resin and 7% crossꢀlinked divinybenzene)
was obtained from Tianjin Xingnan Yunneng Polymer
Technology Co. Ltd. The average diameter of the
spherical solid CMPS was about 0.15 mm.
According to the previous reports, hydrophobic
catalyst surface was beneficial to the adsorption of nonꢀ
polar benzene and desorption of polar phenol, leading to
an improvement in selectivity and yield of phenol.
Mesoporous carbon2, silylated mesocellular siliceous
foam (MCF)27, silylated SBAꢀ1528 and CuꢀVꢀHMS29
were efficient supports or catalysts for their affinity.
Chloromethylated polystyrene (CMPS) as fascinating and
promising materials have attracted considerable attention
due to their structural characteristics, such as unique
2.2. Catalyst preparation
DMA16ꢀCMPS and PMoV2 were prepared according to
the previous reports.30,31 PMoV2/DMA16ꢀCMPS was
prepared according to the following procedures. PMoV2
(0.6 mmol), H2O (15 mL), and DMA16ꢀCMPS (2.0 g)
were placed into a round bottom flask fitted with stirrer
and reflux condenser, heated at 333 K for 8 h. The
product was extracted with acetonitrile in Soxhlet
extractor and then washed with water, subsequently dried
at 353 K for 12 h. The total loading of PMoV2 was
determined by ICPꢀAES (0.16 mmol/g).
For comparison, a similar weight percentage of
PMoV2 supported on CMPS without quaternization was
prepared via impregnation method. 0.57 g PMoV2
dissolved in water and then 1.5 g CMPS was added and
the resulting suspension stood for 24 h at 298 K.
Subsequently, the suspension was evaporated and dried at
353 K for 12 h.
microenvironment
hydrophobicity),
(macro
and
mesoꢀpores,
facile separation, commercially
availability, considerable organic compatibility, and
extraordinary stability. Functional groups can be
introduced on the CMPS through the quaternization of
chloromethyl groups and Na7PW11O39 (PW11) was
immobilized on DMA16/CMPS by electrostatic
interactions according to our recent works. The obtained
PW11ꢀDMA16/CMPS showed a similar catalytic activity
to that of homogeneous PW11.30
Therefore, it is highly demanding as well as
challenging for the development of highly efficient and
stable vanadium substituted HPAs heterogeneous
catalysts for direct hydroxylation of benzene to phenol
with H2O2. Herein, we synthesized the HPAsꢀbased
2.3 Catalyst characterization
Fourier transform infrared spectroscopy (FTꢀIR) spectra
were collected on Bruker Vector 22 using the KBr pellet
technique. Xꢀray diffraction (XRD) was performed on a
D8 FOCUS diffractometer operated at 40 kV and 40 mA,
using CuKα radiation in a scanning range of 5ꢀ60° (2
Theta). The UVꢀvis diffuse reflectance spectra (DRS)
were recorded on Varian Cary300 in the range of 200ꢀ800
nm, and BaSO4 was used as a background. Electron
paramagnetic resonance (EPR) spectra were recorded on
a Bruker A300 spectrometer at Xꢀband at room temperatꢀ
ure. Xꢀray photoelectron spectroscopy (XPS) was carried
polymer
catalyst
(PMoV2/DMA16ꢀCMPS)
by
immobilization of H5PMo10V2O40 (PMoV2) on N, Nꢀ
dimethylhexadecylamine functionalized CMPS (DMA16ꢀ
CMPS). PMoV2/DMA16ꢀCMPS exhibited a relatively
high catalytic activity and considerable stability in the
hydroxylation of benzene with H2O2. High dispersion of
PMoV2 on mesoporous and macroporous DMA16ꢀ
CMPS, good benzene adsorption and phenol desorption
ability and V5+/V4+ redox pair in the catalyst are
responsible for the high activity. Meanwhile,
2 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
Catalysis Science & Technology
Page 3 of 23
View Article Online
DOI: 10.1039/C6CY01270A
Journal Name ARTICLE
out on a PHIꢀ5000 Versaprobe spectrometer. Thermo
gravimetric analyzer (TGA) measurements were carried
out on a SDT/Q600 with 10 °C/min heating rate under
nitrogen atmosphere. N2 adsorptionꢀdesorption isotherms
were performed on Micromeritics ASAP2020M+C. Pore
size distributions were obtained by the BarrettꢀJoynerꢀ
Halenda (BJH) method. Inductively coupled plasmaꢀ
atomic emission spectrometry (ICPꢀAES) was carried out
on Opfima 7300V. Scanning electron microscope (SEM)
was performed on FEI Nova Nano SEM450.
Transmission electron microscope (TEM) and scanning
transmission electron microscope (STEM) were
performed on a FEI Tecnai G2 F20 XꢀTwin microscope
at an extraction voltage of 3950 V, gun lens 1 and spot
size 1. The water contact angles at the sample surfaces
were analyzed using the Kruss DAS30 at room
temperature by the sessile drop method. A water droplet
of 10 ꢁL was carefully dropped onto the samples and the
images were taken after 30 s. 31P nuclear magnetic
resonance (31P NMR) was obtained on Avavce 400, and
chemical shifts were referenced to 85% H3PO4 aqueous
solution.
Phenol selectivity (%) = [moles of phenol/(moles of
benzene added ꢀ moles of unconverted benzene)]*100
TOF: mmol phenol/(mmol heteropolyanion in
catalyst*reaction time)
3 Results and discussion
3.1 Compositional and structural information
The composition and structure of CMPS, DMA16ꢀCMPS,
PMoV2/DMA16ꢀCMPS are characterized by FTꢀIR,
XRD, UVꢀvis DRS, EPR, XPS and TGA.
Fig. 1 shows the FTꢀIR spectra of CMPS, DMA16ꢀ
CMPS, PMoV2 and PMoV2/DMA16ꢀCMPS. CMPS
shows two peaks at 1264 and 674 cm−1, which are
assigned to the symmetric and antisymmetric stretching
vibrations of CꢀCl.32 The bands at 3424, 2923, 2852,
1610 cm−1 are also observed, corresponding to HꢀOH,
CH2, CꢀH, C=C (benzene ring) stretching of CMPS,
respectively (Fig. 1a).26 For DMA16ꢀCMPS, the
disappearance of the band at 1264 and 674 cm−1 with the
simultaneous appearance of the new band at 1466 cm−1
(CꢀN+ vibration) confirms the successful quaternization
of DMA16 with CMPS (Fig. 1b).26,33 The FTꢀIR
spectrum of PMoV2 exhibits four characteristic bands
assigned to a Kegginꢀstructured heteropolyacid at 1060
cmꢀ1, 959 cmꢀ1, 864 cmꢀ1 and 786 cmꢀ1 (Fig. 1c), which
are attributed to Vas(PꢀOa), Vas(Mo=Od) (terminal
2.4 Adsorption and catalytic tests
Adsorption tests of benzene and phenol were investigated
according to the previous reports of He.28,29 Different
amount of benzene (4.5, 5.6, 7.9, 9.0 and 11.3 mmol) or
phenol (1, 2, 3, 4 and 5mmol), acetic acid and acetonitrile
(volume ratio 1:1) were mixed to obtain a series of 6 mL
solution. Then 0.1 g of catalyst was added into each
solution and the mixture was stirred at 298 K for 24 h.
The initial and equilibrium concentrations of benzene or
phenol were analyzed by GC.
Benzene (11.3 mmol), acetonitrile (1.5 mL), acetic
acid (1.5 mL), and PMoV2/DMA16ꢀCMPS (0.1 g) were
added to a threeꢀnecked flask equipped with a reflux
condenser, a magnetic stirrer and a thermometer. Then,
30% aqueous hydrogen peroxide (39.2 mmol) was dropꢀ
wise added to the reactor within 30 min, the solution was
conducted for 9 h at 338 K. After reaction, the products
were identified by 7890Bꢀ5977A gas chromatographꢀ
mass spectrometer. The products were analyzed by a SPꢀ
3420A GC equipped with a KBꢀWax column (30 m, 0.32
mm id, 0.25 ꢁm film thickness) with 1,4ꢀdioxane as
internal standard.
oxygen),
Vas(MoꢀObꢀMo),
Vas(MoꢀOcꢀMo),
respectively.21 In addition, the bands at 3423 and 1633
cmꢀ1 are also observed, corresponding to the
crystallization and constitution water, respectively.34 For
PMoV2/DMA16ꢀCMPS, the characteristic bands of
PMoV2 are observed (Fig.1d), indicating that PMoV2 is
successfully immobilized on DMA16ꢀCMPS and the
Kegginꢀstructure of PMoV2 is well preserved.8 However,
the band for PꢀOa (1060 cmꢀ1) is branched into two bands
at 1094 and 1056 cmꢀ1, which is ascribed to the distortion
of the Keggin HPAs framework resulting from the
extension of the conjugated electrons of functionalized
CMPS cations to heteropolyanions, which is consistent
with the results previously reported.16 Moreover, the
slight band shifts at Mo=Od, MoꢀObꢀMo, MoꢀOcꢀMo
compared with those of PMoV2 are assigned to the strong
electrostatic interaction owing to the negatively charged
PMoV2 Keggin unit and the positively charged surface of
DMA16ꢀCMPS. Similar results were observed in the
cases of immobilization of PMoV2 on poly(1ꢀvinylꢀ3ꢀ
propane carboxylation imidazolium]Br), the synthesis of
Benzene conversion (%) = [(moles of benzene added ꢀ
moles of unconverted benzene)/mole benzene
added]*100
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 3
Please do not adjust margins

Please do not adjust margins
Catalysis Science & Technology
Page 4 of 23
View Article Online
DOI: 10.1039/C6CY01270A
ARTICLE
Journal Name
acidꢀbase
bifunctional
heteropolyacids
(HPAs)
the large broad absorption band at 600ꢀ800 nm is
assigned to the charge transfer of V5+→V4+. Similar
phenomenon was obtained by the anionꢀexchange of
PMoV2 with polymeric ionic liquid (PIL)
poly(divinylbenzeneꢀ3ꢀnꢀbutylꢀ1ꢀvinylimidazolium)ꢀBr.15
However, the large broad absorption band at 600ꢀ800 nm
is not obvious, which is attributed to the small amount of
V4+ in the catalyst, which is also confirmed by XPS
analysis.
nanocatalyst and 12ꢀphosphotungstic acid immobilized
on activatedꢀbentonite.19,35,36
Fig. 2 shows the XRD patterns of PMoV2, DMA16ꢀ
CMPS, PMoV2/DMA16ꢀCMPS and PMoV2ꢀCMPS
obtained by impregnation method. The XRD pattern of
PMoV2 presents diffraction peaks of the typical crystal
structure of HPA anions with Keggin structure at 2θ of 8ꢀ
11°, 18ꢀ22°, 24ꢀ30°, 33ꢀ40° (Fig. 2a), as described by
early work.37,38 The XRD pattern of DMA16ꢀCMPS
displays an obvious broadened peak at 2θ of 20° due to
its amorphous texture (Fig. 2b).26,39 For PMoV2/DMA16ꢀ
CMPS, the XRD pattern is similar to that of DMA16ꢀ
CMPS and no characteristic diffraction peaks of PMoV2
were detected (Fig. 2c). FTꢀIR spectrum of
PMoV2/DMA16ꢀCMPS confirmed the presence of
characteristic bands featured for PMoV2 (Fig. 1d),
indicating that PMoV2 is homogeneously dispersed on
DMA16ꢀCMPS, which is too small to be observed by
The existence of V4+ can be further confirmed by EPR
analysis. The EPR signal is observed at 3000ꢀ4000 G for
fresh PMoV2/DMA16ꢀCMPS (Fig. 4a), indicating the
presence of V4+ in the catalyst. This might be ascribed to
the strong electronic interaction between heteropolyanion
and DMA16ꢀCMPS. Similar phenomenon was also
observed in the case of interaction between organic
cations and inorganic heteropolyanion.18,37 Moreover, the
EPR signal is also observed for recovered
PMoV2/DMA16ꢀCMPS, with the intensities following the
XRD. Similar results were obtained in the cases of the
order: recovered PMoV2/DMA16ꢀCMPS
>
fresh
34
immobilization
H3+xPMo12ꢀxVxO40 on HMS
and
PMoV2/DMA16ꢀCMPS (Fig. 4b), suggesting that fresh
PMoV2/DMA16ꢀCMPS possesses small amount of V4+,
which is consistent with the previous report of Wang.17
The XPS spectra of DMA16ꢀCMPS and
PMoV2/DMA16ꢀCMPS are shown in Fig. 5. For
H3PW12O40 on aminated monolithic poly(divinylbenzeneꢀ
coꢀvinylbenzyl chloride) copolymer.26 Moreover,
PMoV2ꢀCMPS shows the characteristic diffraction peaks
of PMoV2, suggesting aggregates of PMoV2 over CMPS.
The UVꢀvis DR spectra were used to study the nature
of PMoV2 species present on the DMA16ꢀCMPS (Fig. 3).
The UVꢀvis DR spectrum of DMA16ꢀCMPS exhibits
characteristic absorption peaks at 228 nm and 264 nm
(Fig. 3a). The UVꢀvis DR spectrum of PMoV2 consists of
two absorption peaks, assigned to the charge transfer of
O→Mo and O2ꢀ→V5+ in Keggin HPAꢀanion (Fig. 3c),
respectively, which is similar to the results reported
previously.15,40,41 These absorption peaks are also
detected in the UVꢀvis DR spectrum of PMoV2/DMA16ꢀ
CMPS (Fig. 3b). The O2ꢀ→V5+ shifts to 320 nm, and a
blue shift in the UVꢀvis DR spectra is observed along
with changes in the intensity of the bands, which reflects
electrostatic interactions between the PMoV2 and the
cationically modified surface. Similar conclusion was
obtained in case of the immobilization of [PMoV2]5ꢀ on
modified mesoporous MCMꢀ41.42 The result indicates
that PMoV2 has been immobilized on the DMA16ꢀ
CMPS.43 Moreover, the absorption peaks of PMoV2 are
also detected in the UVꢀvis DR spectrum of Rꢀ
PMoV2/DMA16ꢀCMPS and PMoV2ꢀCMPS (Fig. 3d and
e). The FTꢀIR, XRD and UVꢀvis DRS analyses indicate
that the Keggin structure of PMoV2 preserves well after
the immobilization of PMoV2 on the support. In addition,
DMA16ꢀCMPS, the
C
1s spectrum shows two
components at the BEs of 284.5 and 286.0 eV (Fig. 5b),
corresponding to the CꢀC/CꢀH, CꢀN+ (ammonium ions),
respectively.44 The peak at 401.8 eV observed in N 1s
spectrum is attributed to the CꢀN+ (Fig. 5c), as described
by early work of Qiu.45 The binding energy at 197.4 eV
in Cl 2p spectrum is assigned to chloride ion (Fig. 5d),32
indicating the occurrence of quaternarization between
DMA16 and CMPS. The XPS spectrum of
PMoV2/DMA16ꢀCMPS clearly shows the existence of
PMoV2 on DMA16ꢀCMPS (Fig. 5a), proved by the
detection of V 2p and Mo 3d. These results indicate the
presence of electrostatic interactions between PMoV2 and
quaternary ammonium salt groups on DMA16ꢀCMPS.45
The XPS peaks of P 2p, Mo 3d and V 2p are shown in
Fig. 5eꢀg. The peak at 133.8 eV observed in P 2p
spectrum suggests that phosphorus remains to be in the 5+
state (Fig. 5e).34 The Mo 3d spectrum displays
characteristic peaks at 232.4 eV and 235.6 eV, attributed
to Mo6+ (3d5/2) and Mo6+ (3d3/2) (Fig. 5f), respectively,
which is in agreement with the results reported
previously.34,46,47 The
V
2p XPS spectrum of
PMoV2/DMA16ꢀCMPS is deconvoluted into two peaks at
516.7 eV and 515.4 eV (Fig. 5g). The peak at 516.7 eV is
4 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
Catalysis Science & Technology
Page 5 of 23
View Article Online
DOI: 10.1039/C6CY01270A
Journal Name ARTICLE
attributed to the V5+ species, while the peak at 515.4 eV
corresponds to the V4+ species. Similar results were
obtained in case of vanadia supported on mesoporous
carbon nitride.7 The area ratio of [V5+]:[V4+] is about 3.3,
demonstrating V5+ species is predominant in the
PMoV2/DMA16ꢀCMPS. UVꢀvis DRS and EPR also
confirm the presence of a small amount of V4+,
suggesting that the strong electronic interaction between
PMoV2 and electronꢀrich DMA16ꢀCMPS leads
predominantly to the surface reduction of V5+.48
According to the previous work, the reversible redox
process via V5+/V4+ redox pair was the active sites for
Halenda (BJH) desorption branches, the pore size
distribution curves of DMA16ꢀCMPS and
PMoV2/DMA16ꢀCMPS also show pore structure of
mesopores and macropores. After the immobilization of
PMoV2, the
nitrogen
volumes
adsorbed
by
PMoV2/DMA16ꢀCMPS are smaller than those by
DMA16ꢀCMPS. However, no obvious change is observed
for the shape of adsorptionꢀdesorption isotherms as well
as the pore size distribution for both DMA16ꢀCMPS and
PMoV2/DMA16ꢀCMPS (Fig. 7), indicating that the pore
structure is preserved after the immobilization of
PMoV2.7 The pore structure parameters of DMA16ꢀ
CMPS and PMoV2/DMA16ꢀCMPS are listed in Table 1.
The larger surface area and the smaller pore size and
volume of PMoV2/DMA16ꢀCMPS compared with the
ones of DMA16ꢀCMPS are attributed to the
immobilization of PMoV2 on DMA16ꢀCMPS. Similar
results were obtained by supporting PW11 on neutral
alumina (Al2O3)55 and the preparation of antimicrobial
polymeric resin with Nꢀhalamine and quaternary
ammonium salt groups.32
SEM and TEM were employed to characterize the
porous structure of catalyst (Fig. 8). The SEM and TEM
images of DMA16ꢀCMPS exhibit an irregular porous
structure (Fig. 8a, b), which is consistent with the results
obtained by N2 adsorptionꢀdesorption (Fig. 7b). The
STEM image of PMoV2/DMA16ꢀCMPS is lighter in
comparison with that of DMA16ꢀCMPS, suggesting
PMoV2 is immobilized on DMA16ꢀCMPS.
14,15,37,48ꢀ52
hydroxylation of benzene with H2O2.
Therefore, more V5+/V4+ redox pairs is in favor of
accelerating this hydroxylation reaction.
The TGA curves of PMoV2, DMA16ꢀCMPS and
PMoV2/DMA16ꢀCMPS were performed under N2
atmosphere (Fig. 6). The weight loss of PMoV2 is about
13.8% from 30 °C to 450 °C (Fig. 6a), which is due to the
loss of adsorbed water and crystal water.46 For DMA16ꢀ
CMPS (Fig. 6b), the slight weight loss (5.8%) before 150
°C is attributed to the loss of surfaceꢀadsorbed water, and
a gradual weight loss (29.8%) in the range of 200 °Cꢀ250
°C resulted from the decomposition of the quaternaryꢀ
ammonium groups.33 The further weight loss (59.3%)
from 400 ℃ to 700 ℃ is due to the thermal
decomposition of polymer backbone of CMPS.53 The
TGA curve of PMoV2/DMA16ꢀCMPS is similar to that of
DMA16ꢀCMPS (Fig. 6c), and the final residual amount is
27.5%. Therefore, the loading of PMoV2 on the surface of
the DMA16ꢀCMPS is about 27.5% based on the method
described by Zhu,54 which is similar to the result obtained
by ICPꢀAES.
3.3 Benzene adsorption
The adsorption test results of benzene and phenol on
PMoV2, DMA16ꢀCMPS and PMoV2/DMA16ꢀCMPS are
shown in Fig. 9. The equilibrium concentration of
benzene changes only marginally compared with that of
the initial one on PMoV2 (Fig. 9a). However, both
DMA16ꢀCMPS and PMoV2/DMA16ꢀCMPS show a
lower equilibrium concentration of benzene than the
initial one, and the equilibrium concentration of
PMoV2/DMA16ꢀCMPS is lower than that of DMA16ꢀ
CMPS, suggesting a stronger benzene adsorption on
PMoV2/DMA16ꢀCMPS than that on DMA16ꢀCMPS. The
equilibrium concentration of phenol changes only
marginally compared with that of the initial one on all
samples (Fig. 9b), indicating that phenol is hardly
3.2 Textural and Morphology property
The nitrogen adsorptionꢀdesorption isotherms and BJH
pore size distributions of DMA16ꢀCMPS and
PMoV2/DMA16ꢀCMPS are shown in Fig. 7. The nitrogen
adsorptionꢀdesorption isotherms of DMA16ꢀCMPS and
PMoV2/DMA16ꢀCMPS (Fig. 7a) have the characteristic
feature of the type IV isotherm with an H3 hysteresis loop
at relative pressures of 0.8ꢀ0.95, indicating the existence
of mesopores in both the DMA16ꢀCMPS and
PMoV2/DMA16ꢀCMPS. In addition, an abrupt rise in
nitrogen volume adsorbed appears at higher relative
pressure (p/p0>0.95), suggesting both DMA16ꢀCMPS and
PMoV2/DMA16ꢀCMPS also have macroporous structures
besides mesopores, which is in agreement with the results
reported previously.7,26,46 Based on the BarrettꢀJoynerꢀ
adsorbed
on
PMoV2,
DMA16ꢀCMPS
and
PMoV2/DMA16ꢀCMPS. Similar adsorption phenomenon
was obtained in case of silylated SBAꢀ1528 as support or
CuxꢀVꢀHMS as catalysts.29 Moreover, the surface
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 5
Please do not adjust margins

Please do not adjust margins
Catalysis Science & Technology
Page 6 of 23
View Article Online
DOI: 10.1039/C6CY01270A
ARTICLE
Journal Name
hydrophobicity of catalysts can influence the benzene
adsorption and phenol desorption. Contact angle was
measured to evaluate the hydrophobicity of
PMoV2/DMA16ꢀCMPS. The contact angle of
PMoV2/DMA16ꢀCMPS is 163° (Fig. 9c), indicating the
catalyst is hydrophobic, which is beneficial to benzene
adsorption and phenol desorption. Benzene adsorption
ability increased with the increase of contact angle of the
catalyst, leading to further improvement of the catalytic
performance.27,28 Thus, good benzene adsorption and
phenol desorption ability are responsible for excellent
catalytic performance of PMoV2/DMA16ꢀCMPS for the
hydroxylation of benzene.
PMoV2 occurred over PMoV2ꢀCMPS. PMoV2/DMA16ꢀ
CMPS proves to be an efficient catalyst in hydroxylation
of benzene. Carbon balance for the oxidation of benzene
was calculated in detail (Table S1 in ESI).
Table 3 summarizes the catalytic performance of
various PMoV2ꢀbased catalysts previously reported in
hydroxylation of benzene. PMoV2/DMA16ꢀCMPS
exhibits higher catalytic activity (Table 3, entry 7) than
Py1ꢀPMoV2, CufpdꢀPMoV2, C3N4ꢀPMoV2, Pꢀ[DVBꢀ
VBIM]5PMoV2 and PMoV2@SiO2 (Table 3, entries 1ꢀ5).
The TOF of HPMoV/NH2ꢀSBAꢀ15 is higher than that of
PMoV2/DMA16ꢀCMPS (Table 3, entry 6). However, the
preparation of the catalyst suffered from the drawbacks of
high cost, tedious synthetic steps. Thus, PMoV2/DMA16ꢀ
CMPS is a good and efficient catalyst for benzene
hydroxylation.
4 Catalytic activity
Catalytic activity of PMoV2/DMA16ꢀCMPS was
investigated in hydroxylation of benzene to phenol with
mixture of acetonitrile and acetic acid as the solvent and
hydrogen peroxide as the oxidant. Under the investigated
reaction conditions, no phenol is formed in the absence of
catalyst or in the presence of DMA16ꢀCMPS (Table 2,
entries 1 and 2). PMoV2 is an efficient catalyst for
hydroxylation of benzene to phenol in comparison with
V2O5 in terms of conversion of benzene and yield of
phenol (Table 2, entry 3). However, PMoV2 and V2O5
completely dissolve in reaction medium, leading to
difficulty of catalyst recovery and recycling.
PMoV2/DMA16ꢀCMPS afforded a selectivity of 99.3% to
phenol with a benzene conversion of 22.1% (Table 2,
entry 5). The catalytic activity of PMoV2/DMA16ꢀCMPS
slightly decreased compared to that of PMoV2, but
PMoV2/DMA16ꢀCMPS has the advantages of facile
catalyst recovery and recycling. The high activity of
PMoV2/DMA16ꢀCMPS is attributed to the high
dispersion of PMoV2 on mesoporous and macroporous
DMA16ꢀCMPS, good benzene adsorption and phenol
desorption ability and the presence of V4+ in the catalyst.
For comparison, CMPS without quanterization was used
as support for PMoV2 via impregnation method. The
obtained PMoV2ꢀCMPS exhibited a catalytic activity
similar to that of PMoV2/DMA16ꢀCMPS for the first
time. However, the color of the recovered catalyst
changed from orange to white after the first run. When
the recovered PMoV2ꢀCMPS was reused for the second
time, no phenol was formed. Additionally, leaking of the
P in the filtrate was detected after removing catalysts
according to the 31P NMR data (about 81.6% of P leaking
from PMoV2ꢀCMPS). Combined with the results of the
color change, recovery test and 31P NMR, the leaking of
Direct oxidation of benzene derivatives was
investigated (Table 4). PMoV2/DMA16ꢀCMPS was
active for the oxidation of benzene derivatives. Toluene is
oxidized to derivatives of phenol with 6.19% yield and
73.5% selectivity to derivatives of phenol (entry 1).
Benzoic acid was detected as main byꢀproduct. In the
case of naphthalene, only 2.19% yield of naphthol was
obtained (entry 2), which was due to poor dissolution of
naphthalene in the reaction medium. The catalyst shows
higher activity in the oxidation of ethylbenzene than that
of toluene. Benzyl position was very active and easy to be
attacked by reactive oxygen species, the activity of the
reaction was therefore quite high even with the steric
hindrance of the ethyl groups, which is in agreement with
the previous report of Ma.6 The results indicate
PMoV2/DMA16ꢀCMPS has potential prospects in the
oxidation of benzene derivatives.
5 Catalyst stability
The reusability of catalyst was investigated by a fourꢀrun
test under the optimized conditions (Fig. 10a). As shown
in Fig. 10a, the yield of phenol was 21.5% after the 4th
run and has only slight decrease in comparison with that
in the first run. The TOF value for the four runs was 17.4,
17.1, 17.1 and 17.0, respectively. Meantime, the XRD,
FTꢀIR and UVꢀvis DRS of the recovered
PMoV2/DMA16ꢀCMPS after the 4th cycle was further
investigated. The characteristic bands for PMoV2 are
observed in the FTꢀIR spectrum of PMoV2/DMA16ꢀ
CMPS (Fig. 1e) and the XRD patterns and UVꢀvis DR
spectrum of PMoV2/DMA16ꢀCMPS are similar to those
of the fresh one (Fig. 2e and Fig. 3d), indicating the good
structural durability of the catalyst in this reaction.
6 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
Catalysis Science & Technology
Page 7 of 23
View Article Online
DOI: 10.1039/C6CY01270A
Journal Name ARTICLE
Moreover, the leaking test of PMoV2 from
PMoV2/DMA16ꢀCMPS was also investigated (Fig. 10b),
and the process was carried out based on the
methodology reported by R.A.Sheldon.56 After 4 h,
12.9% conversion of benzene and 96.8% selectivity to
phenol were obtained. Then, the catalyst was filtrated and
the reaction mixture without catalyst reacted for further 5
h, and no changes in the conversion of benzene and
selectivity to phenol are observed (Fig. 10b).
Additionally, no leaking of the P occurred in the filtrates
after removing catalysts according to the result of 31P
NMR. According to the results of catalytic performance
of the reused catalyst, leaking test, FTꢀIR, XRD and UVꢀ
vis DRS, PMoV2/DMA16ꢀCMPS has the advantages of
facile recovery and recycling. Moreover, a possible
reaction mechanism for hydroxylation of benzene with
H2O2 over PMoV2/DMA16ꢀCMPS was shown in ESI.
4 Z. Long, Y. Zhou, G. Chen, W. Ge and J. Wang, Sci.
Rep., 2014, 4, 3651.
5 A.J.J. Koekkoek, W. Kim, V. Degirmenci, H. Xin, R.
Ryoo and E.J.M. Hensen, J. Catal., 2013, 299, 81ꢀ89.
6 J.ꢀH. Yang, G. Sun, Y. Gao, H. Zhao, P. Tang, J. Tan,
A.ꢀH. Lu and D. Ma, Energy Environ. Sci., 2013, 6,
793ꢀ798.
7 J. Xu, Q. Jiang, T. Chen, F. Wu and Y.ꢀX. Li,
Catal.Sci. Technol., 2015, 5, 1504ꢀ1513.
8 Y. Leng, J. Wang, D. Zhu, L. Shen, P. Zhao and M.
Zhang, Chem. Eng. J., 2011, 173, 620ꢀ626.
9. Yuan, X. Gao, Z. Pan, X. Li and Z. Tan, Catal.
Commun., 2015, 58, 215ꢀ218.
10 Y. Zhou, Z. Guo, W. Hou, Q. Wang and J. Wang,
Catal. Sci. Technol., 2015, 5, 4324ꢀ4335.
11 N. Mizuno and K. Kamata, Coord. Chem. Rev., 2011,
255, 2358ꢀ2370.
12 Y. Leng, J. Wang, D. Zhu, M. Zhang, P. Zhao, Z.
Long and J. Huang, Green Chem., 2011, 13, 1636ꢀ
1639.
13 J. Zhang, Y. Tang, G. Li and C. Hu, Appl. Catal. A:
Gen., 2005, 278, 251ꢀ261.
14 L. Chen, Y. Xiang and T. Feng, Appl. Organomet.
Chem., 2012, 26, 108ꢀ113.
15 P. Zhao, Y. Leng and J. Wang, Chem. Eng. J., 2012,
204ꢀ206, 72ꢀ78.
16 P. Zhao, J. Wang, G. Chen, Y.Zhou and J. Huang,
Catal. Sci. Technol., 2013, 3, 1394ꢀ1404.
17 Z. Long, Y. Zhou, W. Ge, G. Chen, J. Xie, Q. Wang
and J. Wang, ChemPlusChem, 2014, 79, 1590ꢀ1596.
18 Z. Long, Y. Zhou, G. Chen, P. Zhao and J. Wang,
Chem. Eng. J., 2014, 239, 19ꢀ25.
6. Conclusions
The catalyst (PMoV2/DMA16ꢀCMPS) was successfully
prepared by immobilization of PMoV2 on functionalized
CMPS and used for direct hydroxylation of benzene to
phenol. PMoV2/DMA16ꢀCMPS exhibited excellent
catalytic performance with 21.9% yield of phenol at
65°C. High dispersion of PMoV2 on mesoporous and
macroporous DMA16ꢀCMPS, good benzene adsorption
and phenol desorption ability and V5+/V4+ redox pair in
the catalyst are responsible for the high catalytic
performance of PMoV2/DMA16ꢀCMPS. Meanwhile,
PMoV2/DMA16ꢀCMPS has the advantages of facile
catalyst recovery and recycling.
19 Y. Leng, J. Liu, P. Jiang and J. Wang, Catal.
Commun., 2013, 40, 84ꢀ87.
Acknowledgements
This work was financially supported by the National
Natural Sciences Foundation of China (Nos. 2090618 and
21236001) and the Natural Sciences Foundation of Hebei
province. (No. B2010000027, B2015202262). We thank
to Prof. J. Zhao for helpful comments.
20 Y. Leng, H. Ge, C. Zhou and J. Wang, Chem. Engin.
J., 2008, 145, 335ꢀ339.
21 Y. Li, Z. Wang, R. Chen, Y. Wang,W. Xing, J.Wang
and J. Huang, Catal. Commun., 2014, 55, 34ꢀ37.
22 H. Yang, J. Li, H. Zhang, Y. Lv and S. Gao,
Microporous and Mesoporous Mater., 2014, 195, 87ꢀ
91.
Notes and references
23 A.S. Badday, A.Z. Abdullah and K.ꢀT. Lee, Renew.
Energy, 2014, 62, 10ꢀ17.
24 H. Yang, J. Li, L. Wang, W. Dai, Y. Lv and S. Gao,
Catal. Commun., 2013, 35, 101ꢀ104.
25 A.N. Kharat, S. Moosavikia, B.T. Jahromi and A.
Badiei, J. Mol. Catal. A: Chem., 2011, 348, 14ꢀ19.
26 M.A. Betiha, H.M.A. Hassan, E.A. ElꢀSharkawy,
1 S.S. Acharyya, S. Ghosh, S. Adak, T. Sasaki and R.
Bal, Catal. Sci. Technol., 2014, 4, 4232ꢀ4241.
2 L. Hu, C. Wang, L. Ye, Y. Wu, B. Yue, X. Chen and
H. He, Appl. Catal. A: Gen., 2015, 504, 440ꢀ447.
3 X. Wang, X. Tan, B. Meng, X.Zhang, Q. Liang, H.
Pan and S. Liu, Catal. Sci. Technol., 2013, 3, 2380ꢀ
2391.
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 7
Please do not adjust margins

Please do not adjust margins
Catalysis Science & Technology
Page 8 of 23
View Article Online
DOI: 10.1039/C6CY01270A
ARTICLE
A.M. AlꢀSabagh, M.F. Menoufy and HꢀE.M.
Abdelmoniem, Appl. Catal. B: Environ., 2016, 182,
15ꢀ25.
27 G. Zhang, J. Yi, J. Shim, J. Lee and W. Choi, Appl.
Catal. B: Environ., 2011, 102, 132ꢀ139.
28 L. Hu, B. Yue, C. Wang, X. Chen and H. He, Appl.
Catal. A: Gen., 2014, 477, 141ꢀ146.
29 L. Hu, B. Yue, X. Chen and H. He, Catal. Commun.,
2014, 43, 179ꢀ183.
30 H. Wang, L. Fang, Y. Yang, R. Hu and Y. Wang,
Appl. Catal. A: Gen., 2016, 520, 35ꢀ43.
31 G.A. Tsigdinos and C.J. Hallada, Inorg. Chem., 1968,
7, 437ꢀ441.
Journal Name
41 J. Zhuang, B. Hu, J. Tan and X. Jin, Transition Met
Chem., 2014, 39, 213ꢀ220.
42 D. Kumar and C.C. Landry, Microporous and
Mesoporous Mater., 2007, 98, 309ꢀ316.
43 R. AlꢀOweini, S. Aghyarian and H. ElꢀRassy, J. Sol-
Gel. Sci. Technol., 2012, 61, 541ꢀ550.
44 Z. Cheng, X. Zhu, Z.L. Shi, K.G. Neoh and E.T.
Kang, Ind. Eng. Chem. Res., 2005, 44, 7098ꢀ7104.
45 J. Qiu, X. Zhou, Q. Mo, F. Liu and L. Jiang, RSC Adv.,
2014, 4, 48931ꢀ48937.
46 S. Benadji, P. Eloy, A. Leonard, B.L. Su, K. Bachari,
C. Rabia and E.M. Gaigneaux, Microporous and
Mesoporous Mater., 2010, 130, 103ꢀ114.
32 Z. Jie, X. Yan, L. Zhao, S.D. Worley and J. Liang,
RSC Adv., 2014, 4, 6048ꢀ6054.
33 L. Hua, J. Chen, C. Chen, W. Zhu, Y. Yu, R. Zhang,
L. Guo, B. Song, H. Gan and Z. Hou, New J. Chem.,
2014, 38, 3953ꢀ3959.
34 S. Benadji, P. Eloy, A. Leonard, B.ꢀL. Su, C. Rabia
and E.M. Gaigneaux, Microporous and Mesoporous
Mater., 2012, 154, 153ꢀ163.
47 Z. Wang, Y. Ma, R. Zhang, D. Xua, H. Fu and J. Yao,
J. Solid State Chem., 2009, 182, 983ꢀ988.
48 P. Borah, A. Datta, K.T. Nguyen and Y. Zhao, Green
Chem., 2016, 18, 397ꢀ401.
49 W. Ge, Z. Long, X. Cai, Q. Wang, Y. Zhou, Y. Xu and
J. Wang, RSC Adv., 2014, 4, 45816ꢀ45822.
50 D. Xu, L. Jia and X. Guo, Catal. Lett., 2012, 142,
1251ꢀ1261.
35 Q. Zhao, H. Wang, H. Zheng, Z. Sun, W. Shi, S.
Wang, X. Wang and Z. Jiang, Catal. Sci. Technol.,
2013, 3, 2204ꢀ2209.
36 R. Liu, X. Xia, X. Niu, G. Zhang, Y. Lu, R. Jiang and
S. He, Appl. Clay Sci., 2015, 105ꢀ106, 71ꢀ77.
37 Y. Leng, J. Liu, P. Jiang and J. Wang, Chem. Eng. J.,
2014, 239, 1ꢀ7.
38 S. Farhadic, R. Zareisahamieh and M. Zaidi, J. Braz.
Chem. Soc., 2011, 22, 1323ꢀ1332.
39 H. Kim, J.C. Jung, S.H. Yeom and K.ꢀY. Lee, In Kyu
Song, J. Mol. Catal. A: Chem., 2006, 248, 21ꢀ25.
40 S. Boudjema, A. ChoukchouꢀBraham and R. Bachir,
Adv. Mater. Res., 2015, 1064, 71ꢀ76.
51 D. Xu, L. Jia and X. Guo, Chin. J. Catal., 2013, 34,
341ꢀ350.
52 W. Wang, G. Ding, T. Jiang, P. Zhang, T. Wu and B.
Han, Green Chem., 2013, 15, 1150ꢀ1154.
53 Z. Weng, J. Wang, S. Zhang, C. Yan and X. Jian,
Catal. Commun., 2008, 10, 125ꢀ128.
54 Y. Zhu, M. Zhu, L. Kang, .Yu and B. Dai, Ind. Eng.
Chem. Res., 2015, 54, 2040ꢀ2047.
55 P. A. Shringarpure and A. Patel, Chem. Eng. J., 2011,
173, 612ꢀ619.
56 R.A. Sheldon, M. Wallau, I.W.C.E. Arends and U.
Schuchardt, Acc. Chem. Res., 1998, 31, 485ꢀ493.
8 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Page 9 of 23
Catalysis Science & Technology
View Article Online
DOI: 10.1039/C6CY01270A
Fig. 1 FT-IR spectra of (a) CMPS, (b) DMA16-CMPS, (c) PMoV2, (d) PMoV2/DMA16-CMPS and (e) R-PMoV2/DMA16-CMPS

Catalysis Science & Technology
Page 10 of 23
View Article Online
DOI: 10.1039/C6CY01270A
Fig. 2 XRD patterns of (a) PMoV2 (b) DMA16-CMPS, (c) PMoV2/DMA16-CMPS, (d) PMoV2-CMPS prepared by impregnation
method and (e) R-PMoV2/DMA16-CMPS

Page 11 of 23
Catalysis Science & Technology
View Article Online
DOI: 10.1039/C6CY01270A
Fig. 3 UV-vis DR spectra of (a) DMA16-CMPS, (b) PMoV2/DMA16-CMPS, (c) PMoV2, (d) R-PMoV2/DMA16-CMPS and (e)
PMoV2 -CMPS

Catalysis Science & Technology
Page 12 of 23
View Article Online
DOI: 10.1039/C6CY01270A
Fig. 4 EPR spectra of PMoV2/DMA16-CMPS and (b) R-PMoV2/DMA16-CMPS

Page 13 of 23
Catalysis Science & Technology
View Article Online
DOI: 10.1039/C6CY01270A
Fig. 5 XPS spectra of (a) XPS wide scan spectra of DMA16-CMPS and PMoV2/DMA16-CMPS, (b-d) C 1s, N 1s and Cl 2p XPS
spectra of DMA16-CMPS and (e-g) P 2p, Mo 3d and V 2p XPS spectra of PMoV2/DMA16-CMPS

Catalysis Science & Technology
Page 14 of 23
View Article Online
DOI: 10.1039/C6CY01270A
Fig. 6 TGA analysis of different samples: (a) PMoV2, (b) DMA16-CMPS and (c) PMoV2/DMA16-CMPS

Page 15 of 23
Catalysis Science & Technology
View Article Online
DOI: 10.1039/C6CY01270A
Fig. 7 (a) N2 adsorption-desorption isotherms and (b) BJH pore size distributions of DMA16-CMPS and PMoV2/DMA16-CMPS

Catalysis Science & Technology
Page 16 of 23
View Article Online
DOI: 10.1039/C6CY01270A
Fig. 8 (a) SEM image of DMA16-CMPS, (b) TEM image of DMA16-CMPS, and STEM images of (c) DMA16-CMPS and (d)
PMoV2/DMA16-CMPS

Page 17 of 23
Catalysis Science & Technology
View Article Online
DOI: 10.1039/C6CY01270A
Fig. 9 The adsorption tests of benzene (a) and phenol (b) on PMoV2, DMA16-CMPS and PMoV2/DMA16-CMPS and contact angle of
PMoV2/DMA16-CMPS (c).

Catalysis Science & Technology
Page 18 of 23
View Article Online
DOI: 10.1039/C6CY01270A
Fig. 10 The reusability test of PMoV2/DMA16-CMPS (a) and the leaking test of PMoV2 from
PMoV2/DMA16-CMPS (b) for benzene hydroxylation (reaction conditions as in Table 2)

Page 19 of 23
Catalysis Science & Technology
View Article Online
DOI: 10.1039/C6CY01270A
Table 1 Surface area, pore size and pore volume of DMA16-CMPS and PMoV2/DMA16-CMPS
Surface area
(m2/g)
Pore size
(nm)
Pore volume
(cm3/g)
Samples
DMA16-CMPS
22.2
30.0
44.5
26.3
0.247
0.197
PMoV2/DMA16-CMPS

Catalysis Science & Technology
Page 20 of 23
View Article Online
DOI: 10.1039/C6CY01270A
Table 2 Catalytic activity of different catalysts for benzene hydroxylationa
Entry
Catalyst
Conv.b (%)
Sel.c (%)
Yield (%)
CBd (%)
1
2
No catalyst
DMA16-CMPS
V2O5
0
0
0
99.7
99.3
99.7
99.6
99.8
99.4
98.8
0
0
0
3
18.6
25.8
22.1
21.4
0
97.5
96.1
99.3
97.8
0
18.2
24.8
21.9
20.9
0
4
PMoV2
5
PMoV2/DMA16-CMPS
PMoV2-CMPS
PMoV2-CMPS
6e
7f
a
Reaction conditions: benzene:V=350:1 (mole), hydrogen peroxide/benzene=3.5:1, solvent of acetonitrile and acetic acid (3 mL,
volume ratio 1:1), 65℃, 9h.
b Conv.: conversion of benzene.
c Sel.: selectivity to phenol.
d CB: carbon balance; Table S1 in ESI shows the calculation details for the carbon balance.
e Prepared by impregnation method.
f The reused catalyst prepared by impregnation method for the second time.

Page 21 of 23
Catalysis Science & Technology
View Article Online
DOI: 10.1039/C6CY01270A
Table 3 Comparison of catalytic performance of various PMoV2-based catalysts for hydroxylation of benzene
Vbenzene
(mL)
1.0
V
H2O2
Wcatal.
(g)
Entry
Catalyst
T (℃) t (h) Yield (%)
TOF (h-1)
(mL)
3.5
2.0
-
1
2
3
4
5
6
7
Py1-PMoV2 (ref. 20)
Cufpd-PMoV2 (ref. 14)
C3N4- PMoV2a (ref. 4)
0.2
80
65
5
6
20.5
24.5
13.6
23.7
21.6
19.0
21.9
4.2
4.6
1.0
0.2
4.0
0.5
130
55
4.5
6
5.9
P-[DVB-VBIM]5PMoV2 (ref.15)
PMoV2@SiO2 (ref. 21)
0.9
3.1
3.0
3.0
4.0
0.1
14.1
13.5
62.2
17.4
1.0
0.15
0.1
60
6
HPMoV/NH2-SBA-15 (ref. 25)
PMoV2/DMA16-CMPS
1.0
60
6
1.0
0.1
65
9
a Using O2 (2 MPa) as an oxidant

Catalysis Science & Technology
Page 22 of 23
View Article Online
DOI: 10.1039/C6CY01270A
Table 4 Direct oxidation of benzene derivatives and naphthalene over PMoV2/DMA16-CMPS
Entry
Substrate
t (h)
Product
Yield (%)
2.79
Sel. (%)
33.1
CH3
OH
CH3
HO
2.89
0.51
2.08
0.38
1.81
5.88
4.46
1.27
21.9
34.3
6.1
CH3
1
9
CH3
OH
COOH
24.7
17.1
81.3
49.8
37.8
10.8
99.3
OH
11
2
OH
CH2CH3
HO
CH2CH3
COOH
3
4
9
9
CHO
OH
Reaction conditions as in Table 3

Page 23 of 23
Catalysis Science & Technology
View Article Online
DOI: 10.1039/C6CY01270A
Table of Contents Entry
H5PMo10V2O40 immobilized on functionalized chloromethylated polystyrene by electrostatic
interactions: a highly efficient and recyclable heterogeneous catalyst for hydroxylation of benzene
Hefang Wanga, Luping Fanga, Yongfang Yanga,*, Li Zhanga, Yanji Wanga,*
a
School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin
300130, China.
*
Corresponding author.
H5PMo10V2O40 immobilized on functionalized chloromethylated polystyrene was used as a
highly efficient and recyclable heterogeneous catalyst for hydroxylation of benzene.