Optimization of Gold Recovery from Sedimentary Rock-Hosted Disseminated Agh-Darreh Gold Deposit in Glycine-Copper-Cyanide Leaching System

Gold extraction has long relied on cyanidation yet faces challenges including toxicity and refractory ore usage. This study explores the glycine-copper-cyanide leaching system's potential for gold recovery from sedimentary rock-hosted disseminated Agh-Darreh gold ore. Initially, cyanidation experiments tested increasing temperatures' impact. Concurrently, classical experiments evaluated key parameters—temperature, time, and sodium cyanide to copper cyanide molar ratio—on gold leaching with glycine. Design of Experiments (DOE) methodology was applied, considering three interaction parameters. Results showed 90% recovery at 50°C, peaking at 93% at 35°C with an 8-h leaching time using the glycine-copper-cyanide system. Increasing the sodium cyanide-to-copper cyanide ratio furthered better gold recovery, attributed to copper glycinate complex formation with glycine, enabling free cyanide redistribution. This study underscores the glycine-copper-cyanide leaching system's efficacy as a cyanidation alternative for efficient gold extraction from sedimentary deposits.