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In Chile, the hydrometallurgical plants are operating below their capacity due to a depletion of copper oxide ores. To obtain suitable pregnant leach solutions (PLSs) for hydrometallurgical plants, leaching solutions combining iodine-based oxidants and hydrogen peroxide in a chloride–acid medium, at room temperature and pressure were studied. Factorial experiments were conducted to evaluate the effects of the different leaching solution reagents (KI, NaIO₃, NaCl, H₂O₂, and H₂SO₄). The results showed that the most influential variable is the H₂O₂ concentration; increasing the PLS concentration from 3 g/L to 15 g/L increased the copper extraction percentage by ~25%. In decreasing order of importance, the factorial experimental results showed that the H₂O₂, H₂SO₄, NaCl, NaIO₃, and KI concentrations affect the copper extraction percentage. The highest copper extraction percentage (i.e., 60.6%) was obtained using a leaching solution containing the highest reagent concentrations. At these conditions, the copper concentration in the PLS was 16.9 g/L. An economic evaluation of the laboratory-scale leaching experiments showed an increase in the unit cost (USD/t Cu) for experiments involving leaching solutions without H₂O₂ because of poor copper concentration in the PLS. As the concentrations of the reagents NaIO₃ and KI, increase, the unit cost increases, because the reagents are relatively expensive and have a limited effect on the copper extraction percentage.