大粒度、高表观比重氧化铈的合成  

Preparation of Ceria with Large Particle Size and High Appearance Density

作　　者：王嵩龄[1] 刘钧云 贾江涛[1] 廖春生[1] 严纯华[1] 

机构地区：[1]北京大学稀土材料化学及应用国家重点实验室 [2]江西明达功能材料有限公司,江西赣州342108

出　　处：《中国稀土学报》2008年第1期117-120,共4页Journal of the Chinese Society of Rare Earths

基　　金：科技部支撑计划(2006BAC02A06)资助项目

摘　　要：通过硝酸和草酸混合溶液对草酸铈沉淀进行淋洗或浸泡,结合缓慢升温灼烧,可以获得大粒度和高表观比重的氧化铈。考察了不同酸度、加酸方式、焙烧时间和温度条件对材料的粒度和表观比重这两个关键指标的影响,获得了优化工艺条件。采用5 mol.L-1硝酸和10 g.L-1草酸的混合溶液对草酸铈样品进行淋洗,并将淋洗滤液循环使用,草酸盐再经缓慢升温灼烧,可稳定获得粒度大于20μm、表观比重高于1.9g.cm-3的氧化铈产品。与其他工艺相比,本方法简便易行,具有成本优势。Cerium is one of the most abundant rare earth elements in both bastnasite and monazite. Ceria has been widely used in optical, catalytic, electrolyte, and sensor materials with unique performances. With the development of functional materials, great interest has been focused on the synthesis and characterization of specific fine/mesoporous ceria powder. In this work, the modified precipitation and recrystallization processes combined with a controlled calcination process for fabricating the ceria with large particle size and high appearance density was reported. During the precipitation, certain amount of mineral acid such as nitric acid served as additives to adjust the precipitation and crystallization processes of cerium oxalates. An appropriate acidic condition could lead the process to the Oswald ripening stage and make the particles become bigger. Thus, the appearance density of powder was increased. The optimized conditions, such as the temperature, the feeding speed, the sort and concentration of acids, and the concentration of cerium-contained stock solution, were investigated and evaluated.

关 键 词：大粒度 高比重 氧化铈 合成 稀土 

分 类 号：O614.3[理学—无机化学]