METHOD FOR PROCESSING NEPHELINE CONCENTRATE Russian patent published in 2003 - IPC

FIELD: chemical technology. SUBSTANCE: invention relates to technology for processing alumosilicate raw, mainly nepheline or nepheline concentrate. Nepheline or nepheline concentrate is decomposed with sulfuric acid, insoluble precipitate is separated and washed out and potassium or ammonium sulfate as potassium or ammonium alum is added to the solution, washed out their from impurities followed by thermic treatment of alum and isolation of alumina from calcined product. Mother liquor after separation of alum is neutralized, mixture of aluminum and iron hydroxides is isolated and sodium sulfate is isolated by evaporation. Invention provides the enhancement of quality of preparing alumina by content of impurities of iron and silicon. EFFECT: improved processing method.