Review article on the technology of leaching of substandard copper concentrates: methods and trends

Recently, due to the depletion of rich copper concentrates, poor, refractory concentrates are increasingly used in copper production. Hydrometallurgical methods are attractive for processing this raw material. This review analyzes modern hydrometallurgical methods for extracting copper from low-grade concentrates. Research focuses on innovative approaches to increase dissolution rates and profitability of leaching refractory copper sulfide minerals. Solving these problems will optimize Cu extraction and expand hydrometallurgy for various ores, improving efficiency and environmental sustainability. Current studies include atmospheric leaching, bioleaching with bacterial mixtures, and autoclave leaching, with optimization of conditions, reagents, and additives to destroy passivation layers and achieve high extraction from chalcopyrite. Hybrid leaching methods are also being developed, combining advantages of different approaches. Each method has advantages and drawbacks, such as passivation layer formation and by-product utilization (sulfuric acid, sulfur, nitrates, iron, chlorine). Overcoming these difficulties remains a key research direction for effective hydrometallurgy. Advances in this field may offer a competitive alternative to traditional pyrometallurgical processing of low-grade copper concentrates.