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. 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。