Gene expression programming for modeling and predicting of leaching of chalcopyrite concentrates using 1-hexyl-3-methyl-imidazolium hydrogen sulfate ionic liquid aqueous solution

= 0.976, MAE = 2.80, and RRSE = 0.152 in the training set. Sensitivity analysis revealed that temperature, oxidant concentration, and particle size were the most influential parameters on the copper extraction percentage. By taking into account practical or economic constraints, the proposed model enables the optimization of the leaching process to maximize copper extraction and minimize material consumption.