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Sub-2 μm large-pore monodispersed mesoporous silica spheres (MMSS) were synthesized by using mixed non-ionic surfactants of dodecylamine (DDA) and dodecylamine polyoxyethylene ether (AC1210) as templates through an alkali-catalyzed silica sol–gel technique combined with the template method. Methanol-H 2 O volume ratio on morphology was researched in detail. In addition, by using hydrothermal treatment, the average pore size of MMSS could be enlarged to 11 nm from 4.4 nm. The mesoporous silica particles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), laser particle size analyzer, X-ray diffraction, N 2 physisorption technique. The synthesized sub-2 μm monodispersed mesoporous silica microspheres were successfully functionalized by dimethyloctadecylchlorosilane and used as a packing material in high performance liquid chromatography (HPLC). [ABSTRACT FROM AUTHOR]

Abstract: CuO-loaded large-pore mesoporous SBA-15 silica was synthesized by a simple and efficient direct route in an acid media. Owing to a mesophase transformation behavior induced by inorganic salts, cubic mesostructued silica was also obtained in this system. Characterization of these mesostructured materials by the XRD, TEM, BET, FT–IR, UV–VIS, XPS, CV and ICP–AES showed that ∼37 wt.% or ∼45 wt.% copper oxide was directly introduced into hexagonal or cubic large-pore mesoporous silica, respectively. The mechanism study revealed that in-situ formation of a large amount of copper oxalate was the key step in this synthesis. The catalytic hydroxylation of benzene to phenol reveals that the direct-synthesized mesoporous CuO/silica showed the special catalytic property in comparison to the post-impregnated samples. [Copyright &y& Elsevier]

The first example of a large-pore framework chromium-silicate containing stoichiometric amounts of hexa-coordinated chromium(III) has been reported. Samples were characterised by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflectance spectroscopy ultraviolet–visible (DR UV–VIS) spectroscopy, thermogravimetry (TG), adsorption of different probe molecules and model catalytic tests; AV-15 is an active catalyst for the liquid phase epoxidation of cyclohexene to cyclohexene oxide, the oxidation of cyclohexane to cyclohexanol and cyclohexanone, and the oxidative dehydrogenation of cyclohexanol to cyclohexanone, under mild reaction conditions (using H2O2, at 50 °C). The catalyst is recyclable without significant loss of catalytic activity, but leaching tests indicate that catalysis is mainly due to some leached chromium species. In gas phase, AV-15 exhibits mainly oxydehydrogenation activity in the conversion of ethanol, 2-propanol and cyclohexanol, using air, yielding the corresponding carbonyl product. [Copyright &y& Elsevier]