HZSM-5 zeolite microboxes with a thin intact shell and large hollow core have been synthesized by a mild alkaline treatment of ZSM-5 single-crystals with Na₂CO₃ solution. The obtained product was characterized by means of N₂ adsorption, XRD, FT-IR, TEM, and temperature-programmed desorption of ammonia. The morphology and architecture of the small zeolite microboxes are exceptionally uniform and regular. On the other hand, the intrinsic crystalline properties in the alkaline treated zeolite are well preserved. Furthermore, the zeolite microbox catalyst exhibits higher activity than the parent HZSM-5 by facilitating the diffusion of molecules.

It has been documented that W-modified Pt catalysts with relatively high tungsten contents are effective for the catalytic transformation of biodiesel-derived glycerol to 1,3-propanediol (1,3-PDO). Herein, we report a new finding that Pt/W–SBA-15 catalysts with extremely low W/Si atomic ratios (≤1/80) exhibit excellent catalytic performance in the hydrogenolysis of glycerol to 1,3-PDO. In particular, a Pt/W–SBA-15 catalyst with the W/Si ratio of as low as 1/640 (Pt/W–SBA-15(1/640)) gave rise to the highest 1,3-PDO selectivity of 70.8% at a high glycerol conversion of 86.8% and thus afforded the highest yield of 1,3-PDO of 61.5%. A combination of characterization techniques evidenced that tungsten was homogeneously incorporated into SBA-15 in the form of isolated tetragonal WO₄ and only displayed Lewis acidity. The particle size of Pt evolved in a reverse volcanic curve with the W/Si ratio, with the smallest size being observed for Pt/W–SBA-15(1/640). Control experiments indicated strong synergy between Pt nanoparticles (NPs) and WO₄ in the hydrogenolysis of glycerol. A probe reaction suggested that Brønsted acid sites were generated in situ on the Pt/W–SBA-15 catalysts in a H₂ atmosphere by the reaction between WO₄ and spillover H atoms from the Pt NPs. It is plausible that the hydrided WO₄ functioned as a highly selective active centre in the hydrogenolysis of glycerol to 1,3-PDO, whereas the Pt NPs played the role of a reservoir of spillover H atoms. Thus, a good match between the isolated WO₄ and the small Pt NPs was responsible for the superior catalytic performance of Pt/W–SBA-15(1/640).

The superior propylene yield of the In ₂ O ₃ -beta composite ( ca. 50%) for the conversion of ethanol to propylene compared to In ₂ O ₃ ( ca. 32%) is due to the fact that zeolite beta in the composite enhances the conversion of the intermediate of acetone to propylene via an additional pathway.

Integrating hierarchical porosity over microporous zeotype materials is an effective way to promote their mass transfer properties and catalytic performances. A combined synthetic strategy using small molecular growth inhibitor 1,2,3-hexanetriol and tumbling crystallization condition to generate hierarchically organized SAPO-11 is herein presented. The addition of 1,2,3-hexanetriol in the synthetic gel of SAPO-11 under agitating conditions significantly altered its crystallization behaviour, resulting in the formation of a hierarchically organized architecture. An underlying nonclassical from-shell-to-core crystallization has been disclosed by time-dependent observation of the formation process. The hierarchically self-organized structure has been characterized by a suite of characterization techniques, such as XRD, N₂ physisorption, SEM, TEM, mercury intrusion measurements, ²⁷Al, ²⁹Si, ³¹P MAS NMR and pyridine adsorption IR (Py-IR). The structure featuring barrel-shaped architecture is comprised of aligned 300–400 nm primary building blocks with voids in between, constructing an auxiliary macro-/meso-pore system open to external surfaces. The catalytic performance of Pt supported on hierarchical SAPO-11 in n-heptane hydroisomerization has been assessed, showing that both catalytic activity and isomer yield have been increased with respect to a conventional sample. As the acidity for the hierarchical SAPO-11 is comparable to the conventional sample, the enhancement in catalytic performance is attributed to the small primary crystal size and macro-/meso-pore-connectivity, that are important for mass transfer.

Promoted oxygen adsorption–desorption properties of smaller Rh₂O₃ nanoparticles supported on Zn-modified γ-Al₂O₃ result in a superior activity for N₂O decomposition.

Chromium oxide supported on alumina was modified with various transition metal oxides by an incipient wetness method. The effect of modifiers on the activity of 20% Cr₂O₃/Al₂O₃ catalyst in the dehydrogenation of EB with CO₂ was investigated. The activity is enhanced for ceria and vanadia modified supported chromium oxide catalysts, whereas the activity is decreased for catalysts modified with cobalt, manganese, molybdenum and zinc oxides. Carbon monoxide was detected in the course of the reaction, suggesting that carbon dioxide, which is one of the most important greenhouse gases, could be utilized as a mild oxidant in the oxidative dehydrogenation of ethylbenzene to styrene over unmodified and modified Cr₂O₃/Al₂O₃ catalysts.