摘要
为了获得同时具有高堆密度、低氯根和细颗粒特征的CeO2,研究了在碱性热水溶液中镧石型碳酸铈向碱式碳酸铈相态转变的条件和特点。结果表明:在95℃下,随着溶液pH值的提高和反应时间的延长,相态转化越彻底,所得产物的颗粒大小和分布范围均减小,堆密度增大,氯根含量降低。当溶液pH在12~13时,经4 h的陈化可以得到纯的碱式碳酸铈。原始碳酸铈的颗粒度为22.3μm,氯根含量为1814 mg·kg-1,堆密度为0.55 kg·L-1,相态转化后的颗粒度下降到1~2μm,氯根含量降低到100 mg·kg-1以下,堆密度上升到1 kg·L-1以上。与此同时,碱的加入可以促进相态转化速度和程度,减少气泡产生。据此,确定了碱的加量。工业应用结果证明,采用该方法可以制备D50为1~2μm,氯根含量小于100 mg·kg-1,堆密度介于1.1~1.2 kg·L-1的CeO2产品。
In order to obtain cerium oxide with high bulk density,low chlorine containing and fine particles,the conditions and characteristics of phase transition from lanthanite type cerium carbonate to basic cerium carbonate in alkaline hot aqueous solution were studied in this paper.The results showed that at 95℃,with the increase of pH of solution and the prolongation of reaction time,the phase transformation becomes more complete,the particle size and distribution range decrease,the bulk density increases and the chlorine content decreases.When the pH of the solution was 12~13,pure basic cerium carbonate could be obtained by aging for 4 h.The particle size(D50)of the original cerium carbonate was 22.3μm,and the chlorine content was 1814 mg·kg-1.The bulk density was 0.55 kg·L-1,the particle size(D50)decreased to 1~2μm,the chlorine content decreased to less than 100 mg·kg-1,and the bulk density increased to more than 1 kg·L-1 after phase transition.At the same time,the addition of alkali could promote the speed and degree of phase transition and reduce the formation of bubbles.On the basis of this,the addition of alkali was determined.The results of industrial application showed that then cerium oxide products with D50 of 1~2μm,chlorine content of less than 100 mg·kg-1 and bulk density of 1.1~1.2 kg·L-1 were prepared by this method.
作者
方中心
丁龙
朱敏萱
张尚虎
韩满璇
申淞夫
李静
周新木
周雪珍
李永绣
Fang Zhongxin;Ding long;Zhu Minxuan;Zhang Shanghu;Han Manxuan;Shen Songfu;Li Jing;Zhou Xinmu;Zhou Xuezhen;Li Yongxiu(Gansu Rare Earth New Material Co.,Ltd.,Baiyin 730922,China;Research Center of Rare Earth and Micronano Functional Materials,Nanchang University,Nanchang 330031,China)
出处
《中国稀土学报》
CAS
CSCD
北大核心
2019年第4期465-472,共8页
Journal of the Chinese Society of Rare Earths
基金
科技部支撑计划项目(2012BAE01B02)
国家自然科学基金项目(51864033)
工信部稀土专项资助
关键词
碳酸铈
相态转化
颗粒度
堆密度
氯根含量
cerium carbonate
phase transformation
particle size
density
chlorine content
