ρ-Al2O3的水化特性研究

Research on hydration properties of ρ-alumina

分别对反应前后的ρ-Al2O3进行XRD及SEM分析,确定反应前后Al2O3的物相及显微结构变化;测定加入添加剂前后浆体温度与时间的关系,从而确定添加剂对ρ-Al2O3水化速度的影响;测定加入添加剂前后浆体的黏度变化,从而测定出添加剂对ρ-Al2O3水化过程的影响。结果表明:1)ρ-Al2O3属于无定形态;2)在没有添加剂的情况下,ρ-Al2O3的水化速率很快,同时释放出大量热量,水化产物主要是一水软铝石、三水铝石和拜耳石;3)加入碳酸钠及六偏磷酸钠的混合物为添加剂后,ρ-Al2O3的水化速率显著降低,释放出的热量显著降低,水化产物主要是一水软铝石。

The phase compositions and microstructures of ρ-Al2O3 before and after hydration were analyzed by SEM and XRD.The influence of additive on hydration speed rate of ρ-Al2O3 was studied by analyzing the relationship between temperature and time before and after adding additive into the slurry.The influence of additive on hydration process of ρ-Al2O3 was also studied by determining the viscosity changing of the slurry before and after adding additive.The results showed that：（1）ρ-Al2O3 was amorphous phase;（2）Without additive,ρ-Al2O3 could react with water quickly with much heat liberation,and the hydration products were boehmite,gibbsite and baeryer stone;（3）After adding the mixture of sodium carbonate and sodium hexametaphosphate as additive into the slurry,the hydration speed rate of ρ-Al2O3 lowered obviously with less heat liberation,and the hydration product was mainly boehmite.