Abstract: AlCl3·6H2O（ACH） was prepared from acid leached solution of coal gangue using HCl gas sparging.The technological conditions of crystallization and the effect of the recycle of the crystallized residual solution on the acid leaching efficiency， impurity enrichment and the crystallization of AlCl3·6H2O were studied.Results showed that the crystallization amount and efficiency of AlCl3·6H2O both increased with the volume of HCl gas sparging increasing and the crystallization temperature decreasing. The process of AlCl3·6H2O prepared from the acid leached solution of coal gangue was discussed.The recycle of the crystallized residual solution made Al and the various impurity elements enriched.The enrichment of impurities would influence the quality of AlCl3·6H2O and the qualified AlCl3·6H2O could be obtained only at first four cycles.

Key words: coal gangue；AlCl3·, 6H2O；crystallization；HCl gas