Separation of Gold and Silver Associated with Copper Ore

Copper, a key resource in the fields of construction, electronics, aerospace, and so on, is often associated with precious metals such as gold and silver in its ores. Simultaneously recovering these precious metals during copper ore processing can significantly enhance resource utilization.

Based on its mineral occurrence characteristics, copper in copper ore is primarily chalcopyrite, followed by chalcocite and tetrahedrite. These minerals are distributed as independent particles or disseminated deposits, and exhibit a prominent "poor, fine, and mixed" pattern. The fine-grained copper ore is complexly interbedded and easily oxidized. Associated gold is often found in sulfides as inclusions, fissures, and intergranular gold, with extremely low concentrations and complex intercalation relationships. Silver is often closely interbedded with chalcopyrite and pyrite, often existing as compounds in the interstices between these minerals. Both are closely associated with sulfide minerals, and copper sulfide, as a core carrier mineral, directly determines the recovery of gold and silver during the beneficiation and smelting processes.

Flotation is the core process for separating gold and silver associated with copper ore. This method utilizes the differences in hydrophilicity and hydrophobicity on the mineral surface to achieve separation through the addition of reagents. Because associated gold and silver are closely interbedded with copper ores, they are enriched simultaneously during the copper separation process. This improves copper separation performance while also enhancing gold and silver recovery.

In actual separation, the appropriate process must be selected based on ore characteristics: preferential flotation is suitable for situations where valuable minerals have significant variations in floatability, prioritizing the target mineral and minimizing subsequent losses. Mixed flotation selects multiple valuable minerals with similar floatabilities into a mixed concentrate, making it suitable for ores with multiple minerals and similar flotation characteristics. Asynchronous flotation tailors flotation conditions to different minerals based on ore properties, achieving efficient recovery. When processing copper ores containing a high concentration of independent gold and silver minerals, process optimization is also necessary to ensure effective enrichment of gold and silver into the copper concentrate, maximizing resource recovery efficiency.