Recovery of Lead from Sulfide Concentrate after Mechanochemical Activation Using Nitric Acid

摘要

Decomposition of lead sulfide concentrates in nitric acidic solutions after ferric (Ⅲ) nitrate addition and mechanical preparation has been investigated. It was found out that the decomposition can be achieved in HNO3 solution (>1.5 mol·L^-1) at the temperature above 85℃. The leaching rate of lead can be increased by means of mechanochemical activation. The use of [Fe(NO3)3-HNO3-H2O] aqueous salt system allows the decomposition of lead sulfide concentrate at room temperature and in this case the concentration of HNO3 does not exceed 0.05-0.1 mol.L^-1, The degree of lead recovery into solution from PbS concentrate reaches 99.3%-99.6c70 with the mechanochemical activation of this concentrate. The insoluble residues after the leaching contain SiO2, S^0, FeCO3 and PbSO4.