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A new type of mesostructured ceria material was synthesized via template-assisted precipitation method and tested for the oxidative dehydrogenation (ODH) of ethylbenzene to styrene by molecular oxygen. The effect of calcination temperature on the catalytic performances of the ceria catalysts has been investigated. Among the catalysts tested, the CeO2-450 sample derived by calcination at 450 °C exhibited the highest ethylbenzene conversion (34%) and styrene selectivity (87%). Comparing the reaction rates for ODH of ethylbenzene (ca. 6.1 mmol ST g h−1 at 450 °C) with the highly active nanostructured carbon-based catalysts in the current literature confirmed the very high activity of these new materials. The superior catalytic performance of the CeO2-450 sample can be attributed to its high specific surface area and enhanced redox properties as revealed by H2-TPR measurements. [ABSTRACT FROM AUTHOR]

Mesoporous sulfated Al2O3–ZrO2 (MSAZ) catalysts with large surface areas and pore volumes after calcination at high temperature (650 °C) and with higher Al2O3 content than 20wt% were successfully prepared from a template of block copolymer (P84). The MSAZ catalysts were characterized by X-ray diffraction (XRD), N2 adsorption, transmission electron microscopy (TEM), 27Al magic-angle spinning nuclear magnetic resonance (MAS NMR), thermogravimetric analysis (TG–DTG), temperature-programmed desorption of ammonia (NH3-TPD) and infrared spectra (IR) of adsorbed pyridine. It is shown that the resulting mesostructured sulfated Al2O3–ZrO2 samples have a well-developed textural mesoporosity. The number of acid sites present on MSAZ catalysts is higher than that on conventional sulfated zirconia, and the former catalysts are more active than the latter one for various acid-catalyzed reactions. [ABSTRACT FROM AUTHOR]

Mesoporous sulfated Al2O3–ZrO2 (MSAZ) catalysts with large surface areas and pore volumes after calcination at high temperature (650 °C) and with higher Al2O3 content than 20wt% were successfully prepared from a template of block copolymer (P84). The MSAZ catalysts were characterized by X-ray diffraction (XRD), N2 adsorption, transmission electron microscopy (TEM), 27Al magic-angle spinning nuclear magnetic resonance (MAS NMR), thermogravimetric analysis (TG–DTG), temperature-programmed desorption of ammonia (NH3-TPD) and infrared spectra (IR) of adsorbed pyridine. It is shown that the resulting mesostructured sulfated Al2O3–ZrO2 samples have a well-developed textural mesoporosity. The number of acid sites present on MSAZ catalysts is higher than that on conventional sulfated zirconia, and the former catalysts are more active than the latter one for various acid-catalyzed reactions. [ABSTRACT FROM AUTHOR]

A mesostructured sulfated tin oxide with large surface area (172 m2/g) has been successfully prepared using a block copolymer as structure-directing agent, which is extensively characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen adsorption, and Thermogravimetric analysis (TG) techniques. The results indicate that the mesostructured sulfated tin oxide was tetragonal crystalline, and catalytic tests show that the mesostructured sulfated tin oxide is much more active than conventional one for esterification and Friedel–Crafts acylation. [ABSTRACT FROM AUTHOR]

Thermally stable mesostructured sulfated zirconia (MSZ) with a high surface area has been successfully prepared by a novel one-step synthetic method involving the alcohothermal processing of zirconium nitrate in the presence of ammonium sulfate. The MSZ samples were characterized using X-ray diffraction (XRD), N2 adsorption measurements, thermal analysis (TG/DTA) and transmission electron microscopies (TEM). It is shown that the resulting mesostructured sulfated zirconia samples are tetragonal crystalline, which have a high specific surface area and a well-developed textural mesoporosity with narrow pore size distribution. Catalytic testing showed that the present mesostructured sulfated zirconia was much more active than conventional sulfated zirconia forn-butane isomerization. [ABSTRACT FROM AUTHOR]

A facile two-step sol–gel method has been developed for the preparation of mesostructured aluminosilicate nano-particles (Si/Al = 7.5) with wormhole-like but uniform pore structures and highly catalytic activities towards bulky hydrocarbon cracking. It is desirable that, as this synthesis takes place in the absence of alkali cations, the mesoporous nano-particulate material is directly obtained in the acid form, making a subsequent ion-exchange and calcination treatment superfluous. [ABSTRACT FROM AUTHOR]

A mesostructured sulfated zirconia with a large surface area (189 m2/g) has been successfully prepared using a triblock copolymer as a structure-directing agent. The resulting material was characterized by XRD, TEM, nitrogen adsorption, FTIR and TG/DTA, which suggested that the mesostructured sulfated zirconia was tetragonal crystalline. Catalytic testing showed that the mesostructured sulfated zirconia was much more active than conventional sulfated zirconia for n-butane isomerization. [ABSTRACT FROM AUTHOR]