Abstract: Using low-grade rhodochrosite and industrial NH₄Cl as raw materials, manganese (Mn) was enriched and recovered by the processes of grinding,mixing,roasting,and water leaching.Experiment results showed that Mn leaching rate can reach more than 95%,when the mass ratio of NH₄Cl and rhodochrosite was 1.1 and roasting at 500 ℃ for 1 h;and the technology realized the recovery and utilization of roasting tail gas (CO₂ and NH₃) by two-stage absorption way.It was nece-ssaryto remove large amount of metal impurities that leaching together with manganese.After hydrolysis to remove iron and NH₄F to precipitate Ca and Mg, purified manganese solution which meet the requirements of the subsequent carbonization and crystallization processes was obtained.At last,the high-purity manganese carbonate was crystallized,which conformed to the standard of Manganese Carbonate for Soft Ferrite Use (HG/T 2836—1997).

Key words: rhodochrosite, ammonium chloride, roasting；enrichment