硫酸浸取法提取粉煤灰中氧化铝

Extracting alumina from fly ash by sulfuric acid

以粉煤灰和硫酸为原料,经活化、磁选、硫酸浸出、硫酸铝溶出、结晶制备出Al2(SO4)3.18H2O。硫酸铝经煅烧、γ-Al2O3碱溶和晶种分解、氢氧化铝煅烧等过程制备出冶金级氧化铝。本文给出了完整的工艺流程,对此工艺进行了详细阐述。在最佳条件下,粉煤灰中氧化铝提取率可达92.3%。

Hydrated alurninium sulfate[Al2（SO4）3,18H2O] were prepared by activating, magnetic separation, leaching by sulfuric acid. leaching by hot water, crystallization processes using fly ash and sulfuric acid as raw materials. Metallurgy grade alumina was prepared by calcining aluminium sulfate, γ- Al2O3 dissolved by alkali, decomposition of sodium aluminate solution and calcining aluminium hydroxide processes. The whole flow process was confirmed. The extracting efficiency of Al203 can reach 91.6 percent under the optimum conditions.