Al2O3扩孔条件的优化及材料性能

Properties and Structure of Al_2O_3 with Large Pore

以硝酸铝为原料,用溶胶-凝胶法制备了具有较大孔径的Al2O3。用正交试验得出了制备较大孔径Al2O3的最佳试验条件:pH=10、表面活性剂的用量为3%、扩孔剂(聚乙二醇-20000)用量为8%,陈化温度为80℃、微波干燥。探讨了焙烧温度对Al2O3的表面积、孔径分布和晶相结构的影响。结果表明:900℃焙烧的Al2O3表面积为148.6 m2/g,大于20 nm的孔体积占总孔容的81%,Al2O3的晶相主要为γ-AlO,约占91.8%。

Al2O3 with large pores was prepared by sol-gel method using Al（ NO3 ）3 as raw material. Optimal experimental parameters are determined by orthogonal experiments as following： pH = 10, 3% surfactant, pore enlarger （PEG-20000） 8%, aging temperature 80 ℃, microwave drying. The influence of calcination temperature on the specific surface, pore size distribution and crystal structure is studied, and shows that the Al2O3 calcinated at 900℃ has a specific surface of 148.6 m^2/g, a distribution of pores with 81% of them above 20 nm, and 91% γ-Al2O3.