晶种水热法制备α-氧化铝微粉的生长动力学研究  

Growth kinetics of α-Al_2O_3 micro powders under seeding hydrothermal synthesis method

作　　者：周振君[1] 郭艳杰[1] 吴学倩[1] 肖素岗[1] 

机构地区：[1]长安大学,陕西西安710061

出　　处：《无机盐工业》2008年第12期15-17,共3页Inorganic Chemicals Industry

基　　金：教育部科学技术重点项目(106151);陕西省自然科学基金项目(2007E2-19)

摘　　要：以硝酸铝为原料,氨水为沉淀剂,得到一水软铝石(γ-A lOOH)沉淀。以该一水软铝石为前驱物,纳米α-氧化铝为晶种,采用水热法直接制备出α-氧化铝微粉。在保温时间为8 h、反应温度从380℃增加到460℃时,水热合成的α-氧化铝微粉的粒径从2.1μm生长到3.5μm;在400℃下,保温时间从8 h增加到36 h时,其粒径从2.3μm增加到4.6μm。据此得出α-氧化铝晶粒生长符合动力学方程:Dn=Dn0+k0.t.e(-Ea/RT),其中晶粒生长指数n=2,活化能Ea=47.37 kJ/mol。分析了α-氧化铝晶体生长机理。Boehmite （γ -AIOOH ） precipitate was obtained with aluminum nitrate as raw material and with ammonia as precipitator, α- Al2O3 micro powders were directly prepared under hydrothermal condition with the obtained boehmite as precursor and with nano - sized α - Al2O3 as seed crystal. With increasing reaction temperatures from 380℃to 460 ℃ for a holding time of 8 h, crystals were found to grow from 2.1 p,m to 3.5 μm in size. The particle size increased from 2, 3 μm to 4.6 μm by varying the holding time from 8 h to 36 h at 400 ℃. The grain - growth kinetics of α - Al2O3 crystal under hydrothermal condition was found to follow the equation, D^n=D0^n＋k0·t·e^（Ea/RT） with a grain - growth exponent n = 2 and an activation energy of Ea =47.37 kJ/mol. The mechanism of α - Al2O3 crystal growth was investigated.

关 键 词：氧化铝微粉 水热合成 生长动力学 α-氧化铝晶种 

分 类 号：TQ133.1[化学工程—无机化工]