二次铝灰制备α-Al_2O_3工艺

探索了以二次铝灰为原料,通过低温碱性熔炼—浸出—晶种分解制备α--Al2O3工艺.研究了碱灰比、盐灰比、熔炼温度、熔炼时间、浸出温度、浸出时间和固液比等因素对铝及硅浸出率的影响.探讨了使用晶种分解法处理浸出液制取氧化铝的工艺的可行性.结果表明:优化制备条件为碱灰比1.3,盐灰比0.7,熔炼温度500℃,熔炼时间60 min,浸出温度60℃,浸出时间30 min,固液比1∶4;铝浸出率最高可达92.71%;晶种分解法处理浸出液的后续工艺可行有效.

Preparation process of α-Al2O3 from secondary aluminum dross

The preparation of α-Al2O3 with a process of low-temperature alkaline melting,leaching and seed precipitation was explored by using secondary aluminum ash as a raw material.A series of experiments were done to investigate the effects of factors such as alkali-to-dross ratio,salt-to-dross ratio,smelting temperature,smelting time,leaching temperature,leaching time and solid-to-liquid ratio on the leaching rates of Al and Si.The feasibility of using seed precipitation as a successive treatment technology of leachate to prepare alumina was discussed.The optimum conditions of the process were determined as follows: alkali-to-dross ratio 1.3,salt-to-dross ratio 0.7,smelting temperature 500 ℃,smelting time 60 min,leaching temperature 60 ℃,leaching time 30 min,and solid-to-liquid ratio 1∶4.The leaching rate of aluminum can reach to 92.71%.It is indicated that seed precipitation as a successive treatment technology of leachate is feasible and effective.