WANG Yongqing, HOU Jingpeng, CHANG Qibing, ZHOU Jian’er

(School of Materials Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen 333403, Jiangxi, China; Key Laboratory of Jiangxi Universities of Inorganic membrane, Jingdezhen 333001, Jiangxi, China)

Abstract: According to Stoke equation, a large settling velocity of coarse particles will result in the bad stability of a suspension. The irregular and global coarse alumina powders with the average particle size of 5μm were researched. To increase the suspension’s stability, the increased specific surface area of the coarse particles is proposed to increase the interaction between the coarse powder and the added organic reagent through a nano alumina coating prepared on the coarse particles’ surface. The nano coating was prepared by solvent thermal method. The effect of the content of the dispersant and the stabilizer on the stability of the alumina suspension was researched. The results show that the specific surface area of coarse alumina powders can be increased by the nano coating, which strengthens the interaction between the coarse powder and the added organic reagent. This is an effective way to increase the stability of the suspension prepared with coarse powder.

Key words: suspension; coarse alumina; stability; nano alumina; settling height