Technology of Secondary Niobium Raw Material Recovery

In work the results of researches on processing of niobium's sublimates electron-beam remelting are submitted. Problem of sublimate processing is connected with inconstancy and heterogeneity of chemical and phase compositions. Existing technologies don't provide high extraction of niobium. They are expensive and ecologically unsafe. An offered combined technology allows receiving chemical concentrates, containing 60–70% niobium, by oxidizing roasting of sublimates and subsequent steps leaching of cake by alkali and acid solutions. By methods of rational planning of the metallurgical experiment and kinetic analysis of periodic processes, semiempirical multifactor models of the sulfuric acid leaching of oxidized Al–Nb sublimates by the solutions are obtained. The results of larger scaled laboratory tests indicate the adequacy of the obtained regularities to actual processes, as well as the possibility of practical implementation of the suggested combined technology for processing sublimates of the electron-beam remelting of niobium.