| Microporous materials are widely used in catalysis, adsorption and separation field due to the small pore size, high internal surface area, highly hydrothermal stability. However, the small pore size of micropores hinders the diffusion of reactants and products. So, the microporous materials cannot be used in the reactions with large molecules. Compared with microporous materials, mesoporous materials possess the larger pore size and the thicker channels. Namely, they can cover the shortage of the microporous materials to a certain degree and deal with large molecules. While, the mesoporous materials show poor hydrothermal stability, and the shortcomings affect the development of the mesoporous materials. It is highly desirable to obtain the hierarchical porous materials because of the limitation of the materials with the single channel. The hierarchical porous materials combining the advantages of microporous and mesoporous structure can improve the ability of zeolites.1,2-Diphenylethane (PXE) is an appropriate solvent for the pressure-sensitive record materials, and can be obtained by the alkylation of o-xylene with styrene. The porous silica materials were synthesized with P123 and PIL as the co-templates by the hydrothermal method. Moreover, HPW supported on micro/mesoporous materials were prepared by impregnation method. The catalytic properties of the catalysts were assessed in the alkylation of o-xylene with styrene.The micro/mesoporous silica materials PIL-X-Y were synthesized by the hydrothermal method using ionic liquid (triethylamine acetate) as the microporous template and P123 as the mesoporous template. The influence of the mass ratio of PIL to co-templates (X) and crystallization temperature (Y) during synthesis were investigated. The results showed that the micro/mesoporous silica material PIL-40-373 had a t-plot micropore area of 404 m2-g-1 at the hydrothermal temperature of 373 K, without destroying the ordered mesoporous structure. And compared with the traditional catalyst HPW/SBA-15, the catalyst with the micro/mesoporous materials as the supports showed the higher activity, the PXE yield were above 80%, which may be related to the micropores of PIL-X-Y.A series of micro/mesoporous silica materials BPIL-X-Y with ordered bimodal mesopores have been successfully fabricated using P123 and protic ionic liquid (butylamine acetate) as co-templates. And the influence of PIL content and hydrothermal temperature to the structure of the final materials has been investigated systematically. The results showed that all the materials possess two kinds of mesoporous channels of 4.0 nm and 7.3 nm, which may be caused by the ionic liquid micelles and surfactant P123 micelles, respectively. The micro/mesoporous silica materials with ordered bimodal mesopores supported HPW catalysts had good activity and reusability in the alkylation of o-xylene with styrene, which may be related to the special mesoporous channels of the support and the micropores.A series of micro/mesoporous silica materials are obtained using P123 and high concentration of protic ionic liquid (triethylamine acetate) as co-templates. The structure of final materials was investigated by three important factors:the pH of the solution, the crystallization temperature and the ultrasonic-assisted method. The results showed that the materials with different structure were obtained under the different pH. Among the obtained silica materials, the micro/mesoporous silica material with two kinds of mesoporous channels could be clearly identified when the pH was 2. While, when pH was 3, it could be found that the particular structure like the mesocellular foams were obtained. Moreover, alkylation results exhibited that HPW/HAM-393-3 with large pore size of the support exhibited the best catalytic performance. It can be concluded that the surface area and pore size of the support may contribution to the high catalytic performance, and the large pore size is conducive to the macromolecular reaction.Above all, the micro/mesoporous silica materials using P123 and protic ionic liquid as co-templates possess high surface area, large pore size, and special pore channels. And these materials with advanced properties would act as significant roles in the alkylations. |
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