Preferential hydrometallurgical conversion of zinc sulfide to sulfate from zinc sulfide containing ores and concentrates

摘要

A hydrometallurgical process for converting zinc sulfide in an ore containing zinc sulfide, said zinc sulfide being chemically converted at elevated temperatures to ZnSO4.xH2O which crystallizes substantially in the monohydrate formas ZnSO4.H2O in a conversion solution having a high concentration of H2S4. The process comprises: i) contacting the zinc sulfide of the ore with the conversion solution which comprises a concentration of sulfuric acid selected from the range of about 45% by weight up to about 70% by weight of the conversion solution and at the elevated temperature in the range of 90 DEG C. to less than boiling point of the conversion solution for the selected concentration of sulfuric acid; ii) maintaining the conversion solution at the elevated temperature and at the range of concentration of the sulfuric acid to ensure continued formation of the crystals of ZnSO4.H2O until substantially all available ZnS is chemically converted; and iii) separating the ZnSO4.H2O crystals and remaining solids of the ore from the conversion solution.