(东北大学 有色冶金系， 沈阳 110006)
摘 要: 用水溶液滴定法对Al(OH)3晶种的表面酸性进行了预测定，并用非水溶液回滴法进行了准确测量，确定了晶种表面的酸量，同时研究了不同粒度的晶种对分解过程的影响。实验结果表明，在相同质量下，细粒子的表面酸量较粗颗粒大；当表面积相同时，粗颗粒的单位表面酸量较细颗粒的大。探讨了晶种粒度对分解过程的影响，相同种子比条件下，细粒子具有较高的分解速度和深度。
关键字: 氢氧化铝晶种； 表面酸性；铝酸钠溶液
（Department of nonferrous metallurgy, Northeastern University, Shenyang 110006）
Abstract:The theory of catalysis was applied to precipitation process of sodium aluminate liquor, and the reaction was regarded as a selfcatalyze reaction, gibbsite seed was acted as catalyzer, therefore, the acid and base on its surface will affect its activity directly. In order to decide the acid intensity on seed surface, the acid was premeasured by aqueous titration firstly, then measured exactly by nonaqueous titration method, on the same time, the effect of seed with different particle sizes on precipitation was researched. The result is that the surface acidity of coarse particle is bigger than that of the fine on the condition of the same surface area. As a result, the effect of seed particle size on the precipitation is illustrated.
Key words: aluminum hydroxide seeds; surface acidity; sodium aluminate liquor
