Acid leaching is one of main techniques to extract aluminum from coal fly ash. High pure aluminum sulfate was prepared using coal fly ash, through milling to activation, sulphuric acid leaching, concentrating, and removing iron. The influences of grain size of coal fly ash,the concentration of acid, and reaction temperature on Al2O3-leaching efficiency were studied, and the paper proposed a novel method to remove iron from aluminum sulfate using ethanol. Al2O3-leaching efficiency can reach 80％ with coal fly ash grain size of 20μm, sulphuric acid concentration of 50％ ～60％ and reaction temperature of 200 ～240℃. Impure aluminum sulfate can be high pure product with the iron content less than 0. 005％ through cleaning with ethanol solution which the volume ratio of ethanol to water was about 2:1.%酸浸法是粉煤灰提铝的重要方法之一.以粉煤灰为原料,经球磨活化、硫酸浸出、浓缩结晶、除铁等工艺制备出高纯硫酸铝.研究了粉煤灰粒度、酸液浓度和反应温度对Al2O3提取率的影响,并提出了利用乙醇进行硫酸铝除铁的工艺方法.当粉煤灰的粒度达到201μm,硫酸溶液浓度为50%～60%,反应温度200～240℃时,Al2O3提取率可达80%.硫酸铝粗产品经过醇水体积比约为2:1的乙醇水溶液除杂2次后,其中Fe含量小于0.005%,获得了高纯硫酸铝.
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