超细氧化铝的制备及表征

Preparation and characterization of superfine Al_2O_3 particles

以硝酸铝为原料、柠檬酸作配体、聚乙二醇(PEG)水溶液作分散剂,采用溶胶凝胶以及超临界干燥法制备了氧化铝超细粒子。采用比表面测试、透射电镜等分析手段对超细粒子的形貌、粒径、粒子分布以及比表面和孔分布等进行了研究,考察了干燥方法对氧化铝颗粒大小、比表面积和孔分布的影响。结果表明,超临界干燥方法制备的氧化铝为长100nm、直径10nm左右的高比表面纤维状超细粒子,粒子分布均匀,焙烧后不团聚。作为催化剂的载体,超细氧化铝粒子负载的Co Mo催化剂的HDS活性略高于普通干燥法制备的氧化铝负载的Co Mo加氢脱硫催化剂。

The preparation and characterization of superfine alumina particles were studied by sol-gel and supercritical drying method, transmission electron microscope(TEM) and BET techniques. The samples were divided into two parts, one parts were dried by ordinary method and the others were dried under the supercritical condition of alcohol. The results show that superfine alumina particles with high specific surface areas, large pore volume with the length of 100 nm and large average pore diameter of 10 nm can be obtained by supercritical drying of alumina gel. The calcinations of superfine particles could alter the crystal form, therefore optimize the physical properties of superfine particles. The HDS evaluation results show that the superfine alumina particles supported Co-Mo catalysts are more active than the common alumina supported Co-Mo HDS catalyst.