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Highly ordered three-dimensional (3DOM) macroporous polyoxometalate (POM)-based zirconia hybrids with relatively high surface area and interconnected pore structure have been fabricated by colloidal crystal template method. Owing to the evenly distributed POM active sites, large-scaled 3D ordered macroporous structure, and high porosity of as-synthesized POM-based ZrO2 composite, it exhibits excellent extractive-oxidative desulfurization activity and recyclability. 500 ppm of dibenzothiophene (DBT) in the model fuel can be removed within 2 h under mild conditions and no obvious loss of catalytic activity even after 20 times. The oxidative reaction of DBT follows pseudo-first-order kinetics, corresponded to an Arrhenius activation energy of 61.1 kJ/mol.

In this study, ordered meso-macroporous titania–silica–polyoxometalate (HPW/SiO2–TiO2) material was prepared in one-pot by evaporation-induced self-assembly (EISA) method, with non-ionic surfactant (P123) and monodisperse polystyrene microspheres applied as co-structure-directing agents. And the oxidative desulfurization (ODS) application of as-synthesized hierarchical nanocomposite materials was tested in model fuel. The characterization results of catalyst suggested that Keggin-type polyoxometalate was successfully incorporated into the ordered meso-macroporous SiO2–TiO2 framework. Moreover, the effect of Lewis acid center of the HPW/SiO2–TiO2 catalyst on ODS process was investigated. The optimum proportion of titanium and silicon ratio on catalyst was found to be 1:1, which exhibited remarkable catalytic performance on aromatic sulfur compounds at mild conditions. It revealed that Lewis acid sites played an important role in selectively adsorb DBT and its derivatives. What’s More, the combination of Lewis acid sites and ordered meso/macroporous architecture of catalyst will further facilitated the mass transport in ODS process. No decrease in the activity was observed after six runs, indicating a good stability of as-prepared catalyst.

Hierarchically meso/macroporous phosphotungstic acid/TiO2 (HPW/TiO2) have been successfully synthesized by evaporation induced self-assembly method with polystyrene microspheres and block copolymer P123 as templates. The as-synthesized meso/macroporous HPW/TiO2 catalysts were characterized by X-ray diffraction, scanning electron microscope, transmission electron microscopy, nitrogen adsorption–desorption isotherms, Fourier transform infrared spectra and diffuse reflectance UV–Vis spectra. The results indicate that the catalysts possess disordered macropores and highly ordered mesopores, with Keggin type HPW embedded in the porous framework. The meso/macroporous catalysts exhibit excellent catalytic activity in oxidative desulfurization (ODS) of fuels. The catalytic performance of the meso/macroporous catalyst is markedly enhanced compared with that of pure mesoporous analogue under the same conditions. The high performance of the meso/macroporous catalyst should be attributed to the structural characteristics of meso/macopores, which improve the mass transfer and increase the accessible surface area of the catalyst. Moreover, the catalyst shows good recyclability, which makes it a promising catalyst in ODS process.