Sepn. of non:ferrous metals from zinc ore tailings - by selective sulphation and leaching, leaving an iron rich material used as pigment or for iron prodn.

摘要

Recovery of nonferrous metals from goethite-rich residues derived from wet processing of Zn ores is carried out by (a) treating the residue with a sulphating agent at 500-750 (pref.550-650) deg.C and (b) leaching the resulting sulphates from the residue. The sulphatinq agent can be H2SO4 or a SO3-contg. gas, e.g. produced by decompsn. of H2SO4 or a sulphate or derived from a contact process plant. The SO3-contg. gas can be enriched by injecting H2SO4. The treatment selectively removes Zn, Cu, In and Cd, leaving a Fe-rich material suitable for use as a pigment or an iron ore (FL).