| Due to their distinct pore size distributions and large surface areas, mesoporous materials have particular application in catalyst fields and have attracted many attentions until now. However, the synthesis of mesoporous materials is a complex process with influences by many factors together. In all kinds of preparation, a sol-gel method using block copolymer surfactants as template can gain thicker channel walls, resulting in not easy to collapse during calcination and high hydrothermal stability.In our work, mesoporous Nb2O5 was synthesized by the sol-gel method, using a three block copolymer surfactants P123 (EO20PO70EO20) as structure-directing agents and dehydration ethanol as solvent. The purpose of this part is to discuss each factor in the process of synthesis mesoporous Nb2O5. The factors such as different ratios of template and NbCl5, ratios of template and dehydration ethanol, aging time and relative humidity (RH) in aging process were investigated in order to obtain better preparation conditions, control synthesis process and tailor the pore size distributions according to the practicality. In this thesis, a series ratios of template and NbCl5 can all gain mesostructures, but at EO/Nb=1.2, larger pore size distribution was obtained. Changing ratios of template and ethanol did not have significant influences on mesostructures. Prolonging aging time and aging in air moisture would benefit the more regular mesoporous Nb2O5.Moreover, mesoporous Nb2O5, together with ClCH2COOH was used as acid catalyst inα-pinene hydration. At the reaction time 8h, reaction temperature 60℃, the conversion and selectivity could respectively reach 99.47% and 57.02%, showing good activity. Besides, this catalyst could be recycled without loss of activity. Compared with microporous catalysts Hβ, ZSM5(38) and macroporous resin D005Ⅱ, mesoporous Nb2O5 gave better results.
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