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This work reexamines the preparation condition of Al-MSU-SFAU, which is prepared with an assembly method from zeolite Y seed colloidal, and reveals the effect of Si/Al ratio and a secondary hydrothermal treatment on the property of the material, e.g. the texture, the hydrothermal stability, the acidity and the catalytic activity. With the specific condition for preparing Al-MSU-SFAU, the samples with high Si/Al atomic ratios are uniform, but have no crystalline structure and low hydrothermal stability. The samples with Si/Al <5 contain a significant amount of micropores. However, they are also instable and are the mixtures of zeolite Y and mesoporous material. A secondary hydrothermal treatment destroys a part of the mesopores for all the samples irrespective of the Si/Al ratios but reforms the micropores, specifically improves the micropore volume and surface area for the sample with Si/Al = 5. This sample has the long expected micro/meso composite porous structure with higher hydrothermal stability and acidity.

Ionic liquid immobilization is an effective means for preparing metal-free heterogeneous catalysts for the CO2 conversion. Herein, a series of quaternary ammonium ionic liquids functionalized MCM-41 heterogeneous catalysts, integrating hydrogen bond donors and nucleophilic ion sites, were prepared by a post-synthetic modification method for the CO2 cycloaddition reaction. The physicochemical properties of the catalysts were analyzed by XRD, EA, SEM, TEM, BET, FT-IR, TGA, NMR and XPS. The results show that the quaternary ammonium ionic liquids are successfully immobilized onto the MCM-41 molecular sieves. The obtained catalysts maintain an excellent pore structure and have the good thermal stability. The effects of catalytic conditions on the catalytic performance, the recyclability of the catalysts and their generalizability to epoxide substrates were systematically investigated. In addition, the catalytic performance was evaluated for low concentrations of CO2 (20% CO2, 80% N2). The synergy of multifunctional active sites makes the obtained materials exhibit the high catalytic activity without metals, co-catalysts and solvents. Furthermore, a possible mechanism for the conversion of CO2 to cyclic carbonate catalyzed by the MCM-41-N/CH3(1:3) was proposed.

Ordered hexagonal mesoporous x-ZrSi SBA-15 (where x is the Zr/Si ratio) with 0 < x < 0.12 was successfully synthesized, pelletized and impregnated with a Ni-W bifunctional metal to fabricate a series of novel ring-opening catalysts suitable for the conversion of excess aromatics in petroleum refining. Results obtained from N2 isotherm techniques and TEM analysis indicate that these x-ZrSi supports have high surface areas and narrow pore size distributions with well-ordered hexagonal pore structures. NH3-TPD revealed an increase in acidity with Zirconium content for the x-ZrSi support, with a plateau expected as x approaches 0.16. While deposition of Ni-W onto the x-ZrSi support resulted in a significant increase in acidity for low values of x, the impact was reduced as the Zirconium content increased. When normalized with the catalyst surface area, the acidity of both the support and impregnated catalyst was equivalent for a given total metal content to silica ratio.

In this study, an amino-functionalized MCM-41 mesoporous material was prepared via hydrothermal method for the adsorption of chlorogenic acid from Eucommia ulmoides leaf extracts. The as prepared NH2-MCM-41 was characterized by X-ray diffraction, FT-IR spectroscopy and N2 adsorption–desorption isotherms. The results show that have good mesoporous structure. The batch experiments showed that adsorption process was more in line with the pseudo-second order kinetic model, which indicated the chemisorption played an important role in the adsorption process; Isothermal adsorption results showed that the adsorption of chlorogenic acid by NH2-MCM-41 was more consistent with Langmuir model, indicating that multilayer adsorption process occurred. Thermodynamic analyses demonstrated that the chlorogenic acid adsorption on NH2-MCM-41 abided by a spontaneous and exothermic procedure with entropy decreased. The purity of chlorogenic acid could be increased from 17.36 to 85.60% under the optimal conditions t = 9 h, temperature = 333 K, pH 6. These results indicated that NH2-MCM-41 is a promising adsorbent for the separation and purification of chlorogenic acid from Eucommia ulmoides leaf extracts.

The relationship between the initial compositional make up and the ultimate pore structure has been probed by varying the initial amounts of methanol and water relative to the silica precursor. The gels were dried under conditions that were supercritical to the inter-pore liquid to yield aeroglasses. The structure of these materials has been investigated using nitrogen adsorption and mercury intrusion porosimetry. The primary compositional factor in determining the structure of sol-gel materials is the relative amount of water. A secondary but very important consideration is the relative dilution of the silane in the alcoholic solvent. Increasing this dilution has been shown to affect the shape of the isotherm, and the pore size distributions calculated from the adsorption and desorption branches. As the dilution increases the pore diameters show a general increase. This is related to the level of molecular separation between the condensing species. The relationship between the surface area and dilution is not as clear cut; the estimated BET area generally decreases with increasing dilution, with a possible maximum at a dilution of R A=2 (where R A is the molar ratio of the alcohol with respect of the silane). It has been shown that there are intimate relationships between the initial sol-gel chemistry and the final pore structure of the aeroglasses. Manipulation of the various synthesis parameters thus allows control over the final morphology.

The architecture-dependent wettability of three-dimensional (3D), porous anodic aluminium oxide (AAO) membranes with varying surface morphologies including hierarchical, mesh and honeycomb nanostructures is reported. The surface morphology and underlayer structure play different roles in regulating the wetting behaviour of the AAO membranes. For the mild AAO membranes, the wetting behaviour of the ultra-thin top layer is dominated by the surface morphology in which the water contact angles (WCAs) of the AAO membranes with hierarchical, mesh and honeycomb structures are approximately 113.7° ± 4.6°, 94.9° ± 0.7° and 98.8° ± 5.8°, respectively. The wetting behaviour of the 3D, layered AAO membranes is dominated by both the surface morphology and the underlayer structure. Notably, the WCA of the mild AAO membrane with a layered hierarchical structure increases in the second layer (increase in the hole density). The WCAs of the three kinds of layered hard AAO membranes decrease in the second layer (increase in the hole depth) and then decrease slowly or increase in the third transition layer (decrease in the hole density). The WCAs of all the AAO membranes decrease linearly at different rates with the formation of the ordered bottom layer. The above results can facilitate the engineering of nanostructures for controlling the surface wetting behaviour of materials and devices for applications in multiple fields.

The ZrO2-pillared clay with high acidic property has been prepared by reacting 1 wt% colloidal suspension of Na+-montmorillonite with 1 N aqueous solution of ZrOCl2·8H2O and by subsequent heating. The evolution of local structure around zirconium of the intercalant stabilized in-between aluminosilicate layers upon intercalating, drying, and pillaring condition has been systematically studied by X-ray absorption spectroscopy, and compared to those of reference compounds such as ZrO2, and ZrOCl2 · 8H2O and its 1 N aqueous solution. The intercalated zirconium species was identified as the Zr-tetramer, [Zr4(OH)14(H2O)10]2+, with an average molecular volume of 10 × 10 Å2 and a thickness of 4.5 Å. Also it becomes more condensed upon drying and eventually transforms to a zirconium oxide pillar upon calcination.