Aerosol route to TiO2–SiO2 catalysts with tailored pore architecture and high epoxidation activity

Abstract

We present the aerosol-assisted sol-gel preparation of hierarchically porous TiO<sub>2</sub>–SiO<sub>2</sub> catalysts having a sphere-like shell morphology and a high Ti dispersion. In order to control the porosity at the micro-, meso- and macro- levels, we use the evaporation-induced self assembly (EISA) of a surfactant, possibly combined with polymer beads as hard templates. These catalysts are tested for the epoxidation of cyclohexene with cumene hydroperoxide as oxidant, and their performance is compared to the reference TS-1 zeolite. The high catalytic performance observed with the catalysts prepared by aerosol stems from their high specific surface area, but also from the short diffusion path length generated by the meso-/macro-pore architecture which provide entryways for bulky reactants and products.

Dealumination-controlled strategy mediates Ti–Y zeolite with cooperative active sites for selective oxidations

“…7C), two wide bands centred at about 460.2 and 465.5 eV were associated with 2p 3/2 and 2p 1/2 photoelectrons of isolated Ti ions in the zeolite framework. 38 Besides, almost no signals related to polymerized TiO 2 species at 458.2 eV were found among these spectra. 38,39 There was one common rule for UV-vis, FT-IR and XPS spectra, namely, the intensities of the corresponding signs were boosted at the beginning and afterwards lowered down.…”

Synthesis and In-Depth Characterization of Ga-Based Structured Catalysts: Enhancing Glycerol Conversion

“…A few examples are the production of SiAl oxides for hydrocarbon cracking, SiW and SiMoAl oxides for the metathesis of olefin, SiTi oxides for selective oxidation and recently the synthesis of surface functionalized metallosilicate catalysts [13,[19][20][21][22][23][24][25]. To the best of our knowledge, the synthesis of mesoporous Ga-silicates via aerosol process has never been reported.…”

Hybrid Chemo-Biocatalysts Prepared in One Step from Zeolite Nanocrystals and Enzyme-Polyelectrolyte Complexes

“…Moving further, it is appealing to envisage a more direct procedure to form a GOx/TS-1 hybrid catalyst directly in one step by spray drying of a precursors suspension containing both the zeolite nanocrystals and the enzyme. On the one hand, aerosol processing is well suited for the preparation of many types of inorganic heterogeneous catalysts (38)(39)(40)(41)(42)(43)(44)(45)(46). In fact, aerosol methods were already demonstrated to be successful and scalable to form TS-1 microspheres with a hierarchical porosity (47).…”