METHOD FOR PROCESSING OF REBELLIOUS SILVER-, GOLD-CONTAINING MATERIALS, ORES AND CONCENTRATES Russian patent published in 1995 - IPC

FIELD: hydrometallurgical methods for processing silver-gold ores, concentrates and slimes in which noble metals are associated with manganese, copper, lead and nickel oxides. SUBSTANCE: method consists in treatment of initial ground material with acids (hydrochloric, sulfuric, nitric, bromhydric and hydroiodic acids) with introduction and/or maintenance of total concentration of manganese oxides in terms of manganese dioxide amounting to 3-6 mas. % in the presence of complexing agent (chloride-ion, bromide-ion, iodide-ion) at S: L=1:(4-5) at temperature of 343-363 K for 30-90 min with transfer of gold and silver into solution. Initial material containing manganese of lower oxidation degree is preliminarily calcined in air at temperature of 800-825 K. In case of processing gold-silver-containing material with silver content in excess of 1 kg per ton, first, selective leaching of silver is undertaken, and remaining solid phase with silver concentration of less than 1 kg per ton is directed for hydrometallurgical processing. Ion-exchange sorbents are introduced in pulp to simplify separation from solid phase. EFFECT: reduced power intensity, replaced toxic cyanide reagents, increased recovery of gold and silver from lean ores and concentrates, and recovery of metals of platinum group together with gold and silver. 13 cl