尿素均匀沉淀法制备超细α-Al_2O_3粉体

Preparation of ultrafine α-Al_2O_3 powder by homogenous precipitation

以Al2(SO4)3和CO(NH2)2为原料,通过均匀沉淀法制备出前驱物Al(OH)3,并煅烧得到超细α-Al2O3粉体。研究CO(NH2)2和Al2(SO4)3的摩尔比、Al2(SO4)3起始摩尔浓度、反应温度、反应时间等对前驱物制备的影响。利用X射线衍射仪、扫描电镜、热重/差示扫描法(DTA/TGA)等多种现代分析检测技术对粉体的性能进行了表征。结果表明:在CO(NH2)2和Al2(SO4)3的摩尔比为10:1、Al2(SO4)3起始浓度为0.05mol/L、反应温度为90℃、反应时间为60min的条件下,能得到分散性能良好、粒径为2μm左右且粒度分布均匀的球形超细α-Al2O3粉体。

Al（OH）3 was synthesized as the precursor by the precipitation reaction of aluminum sulfate and urea, which was calcined to get ultrafine α-Al2O3. The effects of mole ratio of CO（NH2）2 to Al2（SO4）3, initial concentrations of Al2（SO4）3, reaction temperature and reaction time on the preparation ofα-Al2O3 were investigated. The structural properties of powder were characterized by X-ray diffractrometry, scanning electron microscope and DTA/TGA measurements. The results show that spherical ultrafine α-Al2O3 powder with non-aggregation and the average particle size of about 2 μ was produced under the conditions： mole ratio of CO（NH2）2 to Al2（SO4）3 is 10：1, initial concentration of Al2（SO4）3 is 0.05 mol/L, reaction temperature is 90 ℃ and the reaction time is 60 min.