Na2CO3沉淀制备超细Y2O3粉体的研究

Preparation of Ultrafine Yttrium Oxide Powder by Sodium Carbonate

超细Y2O3具有尺寸效应和稀土元素的双重特性,广泛应用于MLCC,超耐热合金等高新材料。在前期获得晶型Y2(CO3)3的基础上,对Na2CO3沉淀制备超细Y2O3粉体进行了深入研究,结果表明:与温度、浓度等条件相比,搅拌陈化过程对Y2(CO3)3粒度的影响较大,可以使针状和片状聚集的类球形Y2(CO3)3粉体逐渐分散转化成粒度更小的颗粒;实验最终在并流加料、反应温度40℃, pH 5.5~6.5, YCl3浓度1.0 mol·L^-1,加料速度10 mL·min^-1,搅拌转速600 r·min^-1, 40℃搅拌陈化48 h的条件下可得到D50=3.77μm,(D90-D10)/2D50=0.70的Y2(CO3)3;在550℃较低温度下焙烧2 h后,得到了D50=2.69μm,(D90-D10)/2D50=0.97的超细氧化钇粉体。研究为Na2CO3沉淀制备超细Y2O3工艺提供基础和可能,对提高Y2O3产品附加值和减少普通Y2O3积压具有重要意义。

Ultrafine yttrium oxide has the dual properties of size effect and rare earth elements, and it is widely used in high-tech materials such as MLCC and superheat resisting alloy. On the basis of obtaining the crystalline yttrium carbonate firstly, and the preparation of ultrafine yttrium oxide powder by precipitation with sodium carbonate was further studied. The results showed that compared with the temperature and concentration conditions, the stirring aging process has bigger influence on the particle size of yttrium carbonate, in which process the needle-like and sheet-like spherical yttrium carbonate powders will gradually disperse into smaller particles. Finally, under the conditions of the cocurrent mode, the temperature of 40 ℃, the pH range of 5.5~6.5, YCl3 concentration of 1 mol·L^-1, the feeding speed of 10 mL·min^-1, and the stirring speed of 600 r·min^-1, at 40 ℃ for 48 h agitation aging, yttrium carbonate with D50=3.77 μm and(D90-D10)/2D50=0.70 can be obtained;the final aged yttrium carbonate was calcined at a lower temperature of 550 ℃ for 2 h, and then ultrafine yttrium oxide powders with D50=2.69 μm and(D90-D10)/2D50=0.97 were obtained. This research provides the basis and possibility for the preparation of ultrafine rare earth yttrium oxide by precipitation of sodium carbonate, which is of great significance for improving the added value of yttrium oxide products and reducing the common yttrium oxide backlog.