公开(公告)号：US5644037A

公开(公告)日：1997-07-01

申请号：US433925

申请日：1995-05-02

申请人： Masami Kaneyoshi ,  Isamu Fujioka ,  Shigeru Sakai

发明人： Masami Kaneyoshi ,  Isamu Fujioka ,  Shigeru Sakai

IPC分类号： C01F17/00 ,  C07C51/41 ,  C07F5/00 ,  C04B35/58 ,  C09K11/08

CPC分类号： C07C51/412

摘要： Disclosed is a method for the preparation of particles of a rare earth ammonium double oxalate by mixing a first aqueous solution of ammonium oxalate and a second aqueous solution of a water-soluble rare earth salt. The double oxalate particles have a polyhedral particle configuration with a uniform particle size distribution, from which a rare earth oxide powder of a polyhedral particle configuration with good flowability can be obtained by calcination, when the first and second aqueous solutions are prepared under exact control of the concentrations of the respective ionic species and the aqueous slurry containing the precipitates of the double oxalate is subjected to an aging treatment during which changes take place in the particle morphology and in the crystallographic structure of the double oxalate particles.

摘要翻译： 公开了通过混合草酸铵的第一水溶液和水溶性稀土盐的第二水溶液来制备双草酸稀土铵的颗粒的方法。 双草酸盐颗粒具有均匀粒度分布的多面体颗粒构型，当第一和第二水溶液在精确控制下制备第一和第二水溶液时，可以通过煅烧获得具有良好流动性的多面体颗粒构型的稀土氧化物粉末 对含有双草酸盐的析出物的各离子种类和含水浆料的浓度进行时效处理，在该处理期间，在双重草酸盐颗粒的颗粒形态和晶体结构中发生变化。