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The Keggin‐type P‐Mo‐W polyoxometalate‐based ionic liquids ([VimAm]Br‐POM, POM is PMo6W6O40) were facilely supported on the green fiber (CA) to obtain a kind of bar‐shaped catalyst. The [VimAm]Br‐POM@CA showed an outstanding oxidative desulfurization performance for model oil and real oils with H2O2 as oxidant, mainly due to the dual role of the [VimAm]Br‐POM with the high activity and its excellent dispersion on CA. The dibenzothiophene (DBT) in model oil could be almost completely removed with [VimAm]Br‐POM@CA‐2 in 60 min at 60 °C without adding other extractants, in which [VimAm]Br acts as this role. Meanwhile, the influences of reaction temperature, molar ratio of H2O2/S, catalyst dosage, and different sulfur‐containing compounds were also investigated. Interestingly, the pretty low activation energy (0.1875 kJ/mol) has been achieved, and no significant loss of activity even after being reused for 5 cycles. The combination of IL‐POM and CA is an efficient strategy to obtain a newly kind desulfurization catalyst, with remarkable results on catalytic efficiency and reuse ability at the same time. [ABSTRACT FROM AUTHOR]

• A novel magnetic catalysts was synthesized and characterized. • Different amount of connecting parts exposes the various number of –OCH 3 in catalysts. • Various numbers of exposed groups shows different oxidative desulfurization efficiency. • The catalyst can be easily recovered and reused by external magnet. Magnetic-heteropolyacid mesoporous catalysts have been obtained, in which magnetic Fe 3 O 4 in the center of MCM-41 mesoporous materials and APES (3-aminopropyl-triethoxysilane) used to link heteropolyacid. To noted, for the various molar ratio APES used in the synthesized process, different numbers of –OCH 3 were exposed in the final products (zero, one and two), named Fe@MP-1, Fe@MP-2 and Fe@MP-3, respectively. Interestingly, the three kinds of catalysts exhibited the various DBT removal efficiency during the oxidative desulfurization process, mainly due to their structure variance leading to be the research focus in this work. Among them, under the oxygen in air as oxidant, Fe@MP-1, with no –OCH 3 exposed outside, showed the excellent desulfurization activity with 100% DBT conversion in 90 min and behaved nearly no obvious decrease after at least 8 recycling times. Thus, the certain amount of APES, used to link active components with supporters, is suggested as an effective aspect to increase the oxidative desulfurization efficiency and maybe the different types of linkage also show the various influence, which will be focused on in our further researches. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Transition metal modified heteropolyacid was synthesized and calculated under DFT. • Fibre and MCM-41 were compared to the oxidative desulfurization behavior. • Under O 2 , L-Co-PMF exhibits excellent catalytic performance for deep desulfurization. • Desulfurization condition is mild with very low loss of desulfurization efficiency. • The catalyst can be easily recovered and reused more than 10 times. Abstract Heteroplyacid system exhibited a wide advantage as catalysts, mainly after the modification. In this paper, the density functional theory (DFT) calculations were used to evaluation the influence of electrochemical properties by the shape of the frontier molecular orbitals (MOs), proving the important role of the close relationship between the MOs of different metal modified heteropolyacid and the oxidative desulfurization performance. The obtained results showed that the Co2+ ion introduced into the PMo, as the position of the addenda atom presented a low gap of HOMO-LUMO, which was agreement with the desulfurization results. In addition, two different supports, Fibre and MCM-41, were used to synthesize the Co-PMo@MOF-199@ Supports, namely L-Co-PMF and L-Co-PMM, in which the modified heteropolyacid has been encapsulated into the pores with the mixture of metal-organic framework and the porous materials MCM-41/Fibre. The comparison results showed that the Fibre was an optimal, getting 100% desulfurization rate after 90 min under the chosen conditions. Moreover, the shaped catalyst could widely open the industrial application. [ABSTRACT FROM AUTHOR]

A highly active catalyst Keggin type POM-based inorganic-organic compound POM@MOF-199@LZSM-5(PMZ) has been prepared and applied in the catalytic oxidative desulfurization system. Structure and properties of catalyst were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), N 2 adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and so on. The catalyst gave high desulfurization activity in the removal of DBT using O 2 as the oxidant. Under the optimal conditions, the conversion rate reached 100% only in 120 min. The kinetic studies revealed that the oxidative desulfurization can present a pseudo first-order kinetic process and the apparent activation energy was 30.5 kJ/mol. The response surface method also used to optimize the process of oxidative desulfurization. There was little change for the oxidative desulfurization efficiency after 10 recycle times. This enhanced catalytic performance could be attributed to the more filled active species, POM, in the larger porous materials and the good protection measures of dual-function porous material supports. [ABSTRACT FROM AUTHOR]

With the increasing aim of deep desulfurization of fuel, a kind of novel surfactant-type heteropolyacid [(CH 3 ) 2 (C n H 2n + 1 )N(CH 2 )] 2 [POM] (SRL-POM, n = 10, 12, 14 and 16) was successfully synthesized and then it template self-construction of MOF-199 in the pore of MCM-41 (SRL-PMM). This catalyst was exploited to act as a stable heteropolyacid-based one, under the dual protection functions of MOF-199 and MCM-41. Structure was characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), N 2 adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and so on. Direct oxidation of dibenzothiophene (DBT) using O 2 was performed by this surfactant-type heteropolyacid catalyst with 100% selectivity in the oxidation of DBT to sulfones under the optimal conditions and shown a better reusability. Furthermore, the kinetic studies reveal that the oxidative desulfurization can present a pseudo first-order kinetic process, and this work offers an alternative for oxidative desulfurization of real oil samples as well. [ABSTRACT FROM AUTHOR]

A kind of composite catalytic materials, Metal-POM@MOF-199@MCM-41 (Metal-PMM), were obtained by confining MOF-199 encapsulating metallic Keggin POM into mesoporous MCM-41. The catalyst was designed on the stability and efficiency, which MCM-41 could act as a stable cavy for the heterogeneous metallic POM-based catalyst in the oxidative desulfurization process. The structure characteristics of the catalysts were elucidated through XRD, IR, XPS, N 2 adsorption-desorption, SEM and TEM. The reaction rate could be greatly enhanced, up to 99.1%, under Co-PMM as catalyst and O 2 as oxidant. After reaction, the catalyst can be simply recovered and reused more than 5 times without the change of its structure, for the strongly fixation of MOF-199 and MCM-41 to the metallic modified Keggin POM materials. [ABSTRACT FROM AUTHOR]

A catalyst system designed by a kind of hybrid material POM@MOF-199@MCM-41 (PMM) was found by a one pot and POM template self-construction of MOF-199 in the pore of MCM-41. This catalyst was exploited to act as a stable heteropolyacid-based one in the direct oxidative desulfurization process with a feedstock of model oil under O 2 as oxidant. Based on optimal conditions, the DBT conversion reached up to 98.5% and the PMM could be recycled ten times with a slight decrease, which was compared with heteropolyacid only based on MOF-199 and MCM-41, respectively. Additionally, the structure of ordered nano-sized pores of MOF-199 with POM encapsulated in was clear under crystal analysis, which offered strong evidences for the further movement into the MCM-41. [ABSTRACT FROM AUTHOR]

A series highly efficient and stable metallophthalocyanine/La 0.8 Ce 0.2 NiO 3 (ML/LCNO) photocatalysts were prepared by a facile sol–gel and immersion method. The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), TEM, N 2 adsorption–desorption, and UV–Vis. The results revealed that LCNO calcined at 700 °C possessed a perovskite structure with porous, and phthalocyanine not only adsorbed on the surface but also loaded in the pores of the LCNO oxide. The photocatalytic activities of the samples were evaluated by the photocatalytic oxidation of dibenzothiophene (DBT) under simulated sunlight irradiation. It was found that either macrocyclic structure or center metal of phthalocyanine had great influences on the photocatalytic activity of ML/LCNO. The oxidative reactivity of the different macrocycles was found in the order of MPc/LCNO > MTAP/LCNO > MPTpz/LCNO; which of different center metals was CoL/LCNO > FeL/LCNO > MnL/LCNO > NiL/LCNO > CuL/LCNO. The catalysts were reused several times with a slight decrease in activity. Furthermore, this kinetics of photocatalytic oxidation of DBT indicated that the reaction was a pseudo-first-order reaction. [ABSTRACT FROM AUTHOR]

Inspiring by the nucleation theory of MOF materials, a ternary POM-modified catalyst (POM-MOF@Fibercloth) has been firstly prepared. After characterizing the catalysts with several means, those were applied for the oxidative desulfurization (ODS). Importantly, the MOFs play a role to link the two parts between the fibercloth and POMs, under the guidance of cross-linking reaction during the nucleation and growth stages with the former, as well as the chemical bonding with the latter. Furthermore, for the important role of synthetic methods to the introduction of POMs, as well as the MOFs type, the series of comparison experiments have been done. The PMF, under the agitation synthetic method and MIL-101 chosen as MOF materials, showed nearly perfect DBT conversion and could be put into reused at least 12 times without the obvious decrease in catalytic performance. The study may inspire the design and construction of high-performance preformed POM catalysts by employing the MOF materials under the nucleation theory. [Display omitted] • Preformed POM modified catalysts were synthesized and characterized. • MOF has been used to link POMs and fibercloth under the nucleation theory. • The PMF catalyst under the ethyl alcohol as solvent showed an excellent ODS efficiency. • The catalyst can be easily recovered and reused for more than 12 times. [ABSTRACT FROM AUTHOR]

• A new kind of virus-type FeMP catalyst was synthesized and characterized. • Different type of MOF materials have been compared studied in ODS process. • FeCrP shows an excellent desulfurization efficiency and more recycling times. • The catalyst can be easily recovered and reused by external magnet. A newly kind of spinosus loaded-heteropolyacid catalyst Fe 3 O 4 @MOF-PMoW (abbreviated as FeMP, M = Cr, Cu and Zr) has been obtained under one-pot method using the various magnetic MOF materials bases. Detailed characterizations have proved out the spinosus structure, with the stinging surface morphologies outside, which benefits for the excellent desulfurization performance to the larger contact area with sulfur compounds as much as possible. To be noted, the FeCrP catalyst shows the 100% DBT removal in 60 min, while only 97.0% and 91.6% for FeCuP and FeZrP, respectively. The phenomenon is mainly attributed to the larger BET contact area, leading to link more PMoW to react with DBT in oil. In particular, the FeCrP could be applied in ODS process even after 10 times without the obvious decrease in catalytic activity and the same highly desulfurization performance also has founded in real diesel, showing a better using value in actual industrial application. [ABSTRACT FROM AUTHOR]

• A magnetic W-MoO 3 based MOF catalysts were synthesized and employed in ODS process. • Different WO 3 contents in MoO 3 as active species were compared discussion. • The 30-Fe@W-Mo@MOF in the catalyst showed an excellent ODS efficiency. • The catalyst can be easily recovered by external magnet and reused 18 times. • Deep desulfurization of actual diesel could also be achieved with this system. An effective process to remove sulfur compounds from fuel has been explored. The tungsten atoms modified MoO 3 as active species was used to enhance the desulfurization activities, and MOF materials to provide a stable place. Meanwhile, the successful introduction of magnetic Fe 3 O 4 could lead to an easily separation after the reaction with simple external magnet to achieve the catalyst recycling use and the final catalyst was named as Fe 3 O 4 @W-MoO 3 @MOF. To noted, various W contents in catalyst system showed a different influence on the ODS process and the ultra-deep desulfurization result could be obtained once the 30 % W loading amount was introduced. Under the optimal reaction conditions, DBT could be completely oxidized in 60 min and there is no apparent losing of activity after at least 18 times of recycling. As for the actual diesel, it was demonstrated that an excellent reactivity was also achieved. [ABSTRACT FROM AUTHOR]

• MoO 3 modified magnetic catalysts were synthesized and characterized. • Different morphologies of MoO 3 in catalytic system were compared in the ODS process. • The fibroid MoO 3 in the catalyst showed an excellent ODS efficiency. • The catalyst can be easily recovered and reused by the external magnetic field. In this work, deep oxidative desulfurization was attained using a new kind MoO 3 modified magnetic catalysts, in which metal organic framework (MOF-199) as supports and the magnetic Fe 3 O 4 added to provide the extra character for increasing practical use value. The characterization of the as-designed catalysts were assessed by FT-IR, XRD, SEM, TPR and XPS analyses. To be noted, various morphologies of MoO 3 were used to form the final products and compared to discuss their influences on the ODS performance in this work. Among them, the Fe@Mo-4@MOF, containing the fibroid MoO 3 , showed an excellent catalytic performance to the ultra-deep oxidative desulfurization in 45 min, which was mainly attributed to the special morphology of MoO 3 , providing the higher contact area with the DBT to increase the ODS efficiency. Moreover, the possible mechanism was proposed to illustrate the ODS process and only slight decrease of DBT removal was observed after 15 recycling times. [ABSTRACT FROM AUTHOR]

• The large-aperture mesoporous silica spheres was achieved. • The catalyst PMo 10 V 2 /APTES-HMSNS was synthesized by chemical bonding. • The catalytic activity of nanocomposite was tested on the ODS for fuel. • The catalyst can be easily separated and reused at least 8 times. • The possible desulfurization mechanism was proposed by the quenching experiments and GC–MS analyses. A kind of large-aperture mesoporous silica spheres (HMSNS) has been innovatively synthesized via "Stöber- Phenolic resin" assistance, mainly attributed to the similarity on reaction conditions between the Stöber method and phenolic resin polymerization, as well inspired by the idea of obtaining large-aperture carbon spheres by simple etching and removing templates. To develop the high efficiency heterogeneous catalyst for oxidative desulfurization of fuel, the P-Mo-V type polyoxometalate as active sites, which was considered to own great influence on catalytic performance, was dispersedly immobilized onto HMSNS under the chemical bonding, named PMo 10 V 2 /APTES-HMSNS. The PMo 10 V 2 /APTES-HMSNS possessed the ultra-deep ODS performance under the optimal reaction conditions. It is worth mentioning that the 20-Mo 10 V 2 /APTES-HMSNS could catalyze the degradation for the four sulfur-containing components simultaneously, as high as 86.84 %, 99.99 %, 97.84 % and 91.35 % for benzothiophene (BT), dibenzothiophene (DBT), 4-methyl-dibenzothiophene (4-MDBT) and 4,6-dimethyl-dibenzothiophene (4,6-DMDBT). In addition, 20-PMo 10 V 2 /APTES-HMSNS displayed an outstanding reusability at least 8 times and the plausible ODS mechanism has been proposed. [ABSTRACT FROM AUTHOR]

• Three substituted metal phthalocyanine/La 0.8 Ce 0.2 NiO 3 catalysts were synthesized. • The kinetic process for oxidative desulfurization of DBTs was studied. • Various composed catalysts show different oxidative desulfurization efficiency. • The CoTcPc/La 0.8 Ce 0.2 NiO 3 shows the best desulfurization effect and good stability. Among many photocatalysts, metal phthalocyanine-sensitized semiconductor material has become a research hotspot as an efficient deep desulfurization catalyst. In this work, three series modified phthalocyanine, under nitro, amino and carboxyl as substituted groups, have been obtained firstly and named MTNPc, MTAPc, and MTcPc (M = Mn (II), Fe (II), Co (II), Ni (II), Cu (II)). The corresponding metal phthalocyanine/La 0.8 Ce 0.2 NiO 3 composite catalysts have been successfully synthesized by impregnation method. Through the study on the photocatalytic oxidation desulfurization of DBTs under simulated sunlight, it was found the effect of central metal ions on the catalyst activity is related to their valence electron configuration, while the substituted groups are attributed to their own properties. For the further research, the kinetic study has been introduced to restore the actual reaction process, finding it conformed to the quasi-first reactions and the order of desulfurization degree of the catalysts with the same central metal ions and different peripheral substituted groups is MTcPc/La 0.8 Ce 0.2 NiO 3 > MTNPc/La 0.8 Ce 0.2 NiO 3 > MTAPc/La 0.8 Ce 0.2 NiO 3. Besides, the CoTcPc/La 0.8 Ce 0.2 NiO 3 with the best desulfurization performance shows t 1/2 = 74 min and the reused experiment has been done to study their actual use value. [ABSTRACT FROM AUTHOR]