Method for preparing large granularity and large specific surface area spherical yttrium oxide

Abstract

The invention relates to a method for preparing spherical yttria with large granularity and large specific surface area, in particular to a method for preparing the spherical yttria with large granularity and large specific surface area by an yttric inorganic salt solution through an ammonium hydrogen carbonate precipitation method. The preparation method comprises the following steps: the yttric inorganic salt solution and the ammonium hydrogen carbonate aqueous solution directly react to generate a serous fluid containing yttrium carbonate; and subsequently, the serous fluid is added with soluble ammonium salt and is kept stand, matured, filtered, washed and calcined to manufacture the controllable spherical yttria with the granularity D50 of between 20 and 100 mu m and the specific surface area of between 10 and 100 m<2> / g. The soluble ammonium salt is added to reach the aims of regulating and controlling the size of the granularity and the specific surface area of an yttria powder body. An yttria product with large granularity and large specific surface area simultaneously is obtained by the method; sediment has large granularity; the serous fluid has good filtering performance, thereby being easy for industrialized operation; and the whole process is simple and is not limited by special equipment.

Description

technical field [0001] The invention relates to a method for preparing spherical yttrium oxide with large particle size and large specific surface area, and belongs to the technical field of preparation of rare earth oxide powder materials with special physical properties. technical background [0002] Yttrium oxide powder is an important high-tech ceramic raw material and one of the rare earth oxides widely used in phosphors. Yttrium oxide powder has excellent heat resistance, corrosion resistance and high temperature stability, good stability to reducing medium, high dielectric constant (12-14), and is widely used in the fields of electronics, materials, aviation, aerospace, atomic energy and high-tech ceramics. The application of yttrium oxide powder will become more and more extensive, so the requirements for particle size and specific surface area of ​​yttrium oxide powder will be higher and higher. New high-performance rare-earth catalysts and phosphors require large ...

AI Technical Summary

Problems solved by technology

Chinese patent CN1629074A discloses a method for preparing large-grain rare earth oxides. This method uses oxalic acid as a precipitating agent to precipitate a rare earth salt solution, such as nitrate, and dry the obtained precipitate. After calcination, the particle size distribution is normal. 、D 50 Hexahedral rare earth oxides with a relatively complete crystal form larger than 15 μm, but there is a problem of poor fluidity, which is limited in application

Chinese patent CN1195647 relates to the preparation method of large specific surface area and superfine yttrium oxide. First, yttrium nitrate is dissolved in formic acid, then hydrazine is added, and the obtained mixture is calcined at 260-360° C. to obtain yttrium oxide with a specific surface area of ​​10— 50m 2 / g, but particle size≤0.1μm

[0005] At present, in the wet system, large particle size (20-100μm) and large specific surface area (10-100m) are directly prepared by simple soft chemical means such as precipitation method. 2 / g) and spherical yttrium oxide has no report or patent publication

Images