溶胶-凝胶法制备γ-氧化铝膜的微观结构

MICROSTRUCTURE OF γ-ALUMINA MEMBRANES PREPARED BY SOL-GEL TECHNIQUE

用溶胶 -凝胶法制备了γ -氧化铝膜 ,发现γ -氧化铝膜呈( 1 1 0 )择优取向 .前体勃母石凝胶膜的择优取向越明显、焙烧温度越高 ,形成的γ -氧化铝膜的择优取向现象越明显 ,70 0℃是合适的焙烧温度 ,焙烧时间以 1 .5～ 3h为宜 .择优取向现象的存在对γ -氧化铝膜有利 ,( 1 1 0 )择优取向现象越明显 ,膜孔结构越均匀 ,孔径分布越窄 .70 0℃焙烧形成的γ -氧化铝膜比表面积为 2 0 2m2 /g ,孔径范围 1～ 5nm ,占孔体积 90 %的是直径为 2 .0～ 3 .5nm的孔 .

alumina membranes were prepared by sol-gel method. It is found that the γ-alumina membranes exhibit (110) preferred orientation. The higher the preferred orientation of the γ-AlOOH gel membrane and the higher the temperature of sintering with enough sintering time, the higher the (110) preferred orientation of the γ-alumina membrane. Sintering temperature of ~700 ℃ and time of 1.5～3 h are suitable sintering conditions of the membrane. The higher the (110) preferred orientation of the γ-alumina membrane, the more uniform of the pore size distribution of the membrane. At ~700 ℃, γ-alumina membrane with specific surface area of ~202 m2/g, pore size 1～5 nm is obtained and pores with diameter ~2.0～3.5 nm account for 90% (in volume).