METHOD FOR BIOLEACHING AND SOLVENT EXTRACTION WITH SELECTIVE RECOVERY OF COPPER AND ZINC FROM POLYMETAL CONCENTRATES OF SULFIDES

摘要

The invention relates to a method for bioleaching and solvent extraction with selective recovery of copper and zinc from polymetal concentrates of sulfides, comprising a process of bioleaching and reduction of ferric ion and a process of solvent extraction of copper and zinc. The process of bioleaching and reduction of ferric ion comprises a step of conditioning a pulp of concentrates; a step of bioleaching, wherein, once the pulp has been conditioned, it is subjected to a bioleaching process using a plurality of bioreactors of the mixing tank type with a system for the injection and diffusion of air, which allows the handling of a pulp density higher than 15 %; a step of separating solids from a solution rich in metal ions obtained in the bioleaching step; and a step of reduction of ferric ion, wherein the pulp from the previous step is subjected to a step of conversion of the ferric ions to ferrous ions. The step of solvent extraction comprises a step of solvent extraction and electrolysis of copper; a step of arsenic control, wherein, once the copper has been extracted from the solution, the arsenic in said solution is controlled; and a step of solvent extraction and electrolysis of zinc, which uses a zinc-extracting solution based on phosphinic acids.