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Porous carbons derived from castanea mollissima shell are prepared by a simple alkali activation method, and employed as metal-free catalysts for catalytic dehydrogenation of propane to propylene, exhibiting high catalytic performance. The chemical compositions and structural properties of the obtained carbon catalysts are characterized by XRD, SEM, TEM, XPS, TG, He-TPD, Raman spectroscopy and nitrogen sorption techniques, revealing the presence of rich micro-/meso-/macropores and numerous oxygenated functional groups. The catalytic results suggest that the porous carbons obtained by activation of castanea mollissima shell with KOH at 700 °C exhibit the best catalytic performance. And the porous structure with high surface area and abundant oxygen-containing groups of the carbon catalysts are responsible for the high catalytic performance. This catalyst is derived from biomass, has much low cost, and can be widely used in various reactions including propane dehydrogenation.

Monolithic mesoporous carbons were prepared through a simple autoclaving method using citric acid as catalyst instead of HCl. The presence of citric acid plays an important role in determining the structural ordering of the resultant mesoporous structure due to the –COOH groups which can enhance hydrogen interaction between structural directing agent of triblock copolymer F127 and polymeric carbon precursor of resorcinol–formaldehyde resins. The obtained carbons have a hexagonal pore system, uniform pore size of ∼5.0 nm and high BET surface area of ∼758 m2/g. The prepared mesoporous carbons were used as catalyst for dehydrogenation of propane, exhibiting high catalytic activity and stability. After 50 h time-on-stream, the propane conversion of 12.1% was observed with propylene selectivity of 95.1% in the direct dehydrogenation process, while the propane conversion of 20.1% with propylene selectivity of 25.8% in oxidative dehydrogenation process. It has been found that the surface basic groups are active sites.

Mesoporous particles and 1D nanorods of cerium oxides have been prepared by modifying the hydrothermal route of a surfactant-assisted controllable synthesis. Mesoporous cerias were obtained in a sealed glass vessel under continuous stirring, while ceria nanorods were obtained in a Teflon-lined autoclave without stirring. The mesoporous cerias did not show long-range mesoscopic organization, exhibiting a broad mesopore size distribution in the region 8–15 nm. A BET surface area of 100 m2/g with a total pore volume of 0.33 cm3/g is obtained for as-synthesized mesoporous ceria. The ceria nanorods exhibit a cubic crystalline structure after calcination, having the lengths in the range of 150–300 nm and diameters in the range of 10–25 nm. The growth direction of ceria nanorods is along [1 1 0]. A surface area of above 50 m2/g is obtained in the calcined nanorods. These synthesized ceria materials were used as supports of nano-sized gold catalysts, prepared by deposition–precipitation method. Their catalytic activity was evaluated by the low-temperature water-gas shift reaction. The gold/mesoporous ceria catalytic system exhibited higher catalytic activity than gold/ceria nanorods. It is revealed that the mesoporous and nanostructured cerias are of much interest as potential supports for gold-based catalysts that are effective for low-temperature water-gas shift reaction.

New gold catalytic system prepared on ceria-modified mesoporous titania (CeMTi) used as water-gas shift (WGS) reaction catalyst is reported. Mesoporous titania (MTi) was synthesized using surfactant templating method through a neutral [C 13 (EO) 6 –Ti(OC 3 H 7 ) 4 ] assembly pathway. Ceria modifying additive was deposited on MTi by deposition precipitation (DP) method. Gold-based catalysts with different gold content (1–5 wt.%) were synthesized by DP of gold hydroxide on mixed metal oxide support. The supports and the catalysts were characterized by powder X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), N 2 adsorption analysis and temperature-programmed reduction (TPR). The catalytic behavior of the gold-based catalysts was evaluated in WGS reaction in a wide temperature range (140–300 °C) and at different space velocities and H 2 O/CO ratios. The influence of gold content and particle size on the catalytic performance was investigated. The WGS activity of the new gold/ceria-modified mesoporous titania catalysts was compared with that of gold catalysts supported on simple oxides CeO 2 and mesoporous TiO 2 , as well as gold/ceria-modified titania and reference catalyst Au/TiO 2 type A (World Gold Council). A high degree of synergistic interaction between ceria and mesoporous titania and a positive modification of structural and catalytic properties by ceria has been achieved. It is clearly revealed that the ceria-modified mesoporous titania is of much interest as potential support for gold-based catalyst. The Au/ceria-modified mesoporous titania catalytic system is found to be efficient catalyst for WGSR.

The first examples of a new mesoporous form of crystalline β-FeOOH (akaganeite) were prepared by the surfactant-assisted method of nanoparticle assembly using FeCl3 as the precursor and a surfactant of either cationic cetylpyridinium or anionic dodecylsulfonate or nonionic Brij 56 as a hierarchical structure mediator. TEM images indicated the presence of a scaffold-like structure formed through the aggregation and intergrowth of rod-like akaganeite nanoparticles. The synthesized mesoporous akaganeite has a unimodal and very narrow pore size distribution with high surface area, which can be converted to mesostructured α-Fe2O3 (hematite) after degassing at 300°C. Bimodal pore size distributions could be obtained by increasing the synthetic temperature from 40 to 80°C. Mesoporous iron oxides with bicrystalline structure of akaganeite and hydronium jarosite were prepared when using dodecylsulfonate surfactant at 80°C. The surfactants were believed to play an important role in the formation of the hierarchical scaffold-like mesostructure.