中文摘要：

以四水乙酸镁为前驱体,以大米粉形成的凝胶为模板,采用新的凝胶-模板法制备了一系列的氧化镁材料,并用X射线衍射、扫描电镜、低温氮气吸附-脱附、X射线荧光分析、热重-差示扫描量热、CO2程序升温脱附和氨程序升温脱附等手段对样品进行了表征.该方法主要利用大米粉在水中加热形成凝胶来分散镁盐前驱体,再通氧焙烧去除模板从而获得多孔MgO材料.结果表明,制得的MgO具有高比表面积（可达206m^2/g）和双介孔结构（孔径分别位于3.9和5~40nm附近）.与直接焙烧四水乙酸镁制得的MgO相比,这类新型高比表面积MgO具有较多的强碱位和较少的酸性位,并在异丙醇催化分解反应中表现出更高的丙酮收率和选择性,有望成为一类优良的固体碱催化剂.

英文摘要：

A series of solid base MgO materials were prepared by a new gel-templating route using the gel derived from rice powder as the template and Mg（CH3COO）2·4H2O as the MgO precursor. The samples were characterized by X-ray diffraction, scanning electron microscopy, nitrogen adsorption-desorption, X-ray fluorescence, thermogravimetry-differential scanning calorimetry, and CO2 and NH3 temperature-programmed desorption. In this route, magnesium acetate was dispersed by rice gel that was formed from rice powder after heating in water, and the porous MgO material was obtained after the gel template was removed by calcination in oxygen. The as-prepared MgO material has high specific surface area （206 m^2/g） and bi-mesopore structure with pore size around 3.9 and 540 nm. Compared with the MgO prepared by direct thermal decomposition of the MgO precursor, the novel high-specific-surface-area MgO material contains more strong basic sites and less acidic sites and exhibited higher acetone yield and selectivity in isopropanol decomposition, making it a potential solid base catalyst.