低松装密度介孔氧化铝的制备

Preparation of Mesoporous Alumina with Low Apparent Density

以有机醇铝为铝源,采用表面活性剂模板法制备了低密度介孔氧化铝,考察了表面活性剂、水解条件、煅烧温度和时间等对氧化铝松装密度及孔性能的影响,利用N_2吸附-脱附、扫描电镜(SEM)、X射线衍射(XRD)等检测手段对产品进行表征和分析。结果表明,当聚乙二醇(PEG400)加入量为3%,水铝比为7:1,反应温度为70℃,老化时间为2h,煅烧温度为600℃,煅烧时间为3h时,制得的介孔氧化铝松装密度较低,所制备氧化铝为活性γ-Al_2O_3,其松装密度为0.072g/cm^3,孔径分布为5～20nm,比表面积达到498.314 m^2/g。

The mesoporous alumina with low apparent density was prepared using aluminium isopropoxide as raw material by surfactant template method. The effects of surfactant, hydrolysis conditions, calcination temperature and calcination time on apparent density and pore structure were investigated. The synthesized materials were characterized by N2 adsorption and desorption method, scanning electron microscope （SEM） and X-ray diffraction （XRD）. The results showed that the alumina with low apparent density was obtained under the conditions of mass fraction of polyethylene glycol 3%, molar ratio of aluminium isopropoxide to H20 7：1, reaction temperature 70 ℃, aging time 2 h, calcination temperature 600 ℃ and calcination time 3 h. The product was activated 7-alumina with apparent density 0.072 g/cm^33, pore diameter 5-20 nm and specific surface area was 498.314 m^2/g.