The chalcopyrite leaching process has had poor success rates because this mineral shows a slow and incomplete oxidation due a strong passivation in acid solutions and formation of an impermeable layer which impedes the attack. However, the use of some strong oxidizing agents, such as iodine/iodide salts, can be used to increase the reaction rates and break this layer. Also, as an advantage, this compound oxides typical water soluble species than can be found oxidant that typical water-soluble species can be found in caliche mineral. The applications and use of iodide for copper extraction scarcely used however it dissolves successfully many sulfide minerals including chalcopyrite at an acceptable kinetic rate, due to high proton activity created by the acid forming a strong oxidizing agent. This oxidant (iodide) offered an alternative to the leaching process along or with other salts commons. In addition to the above-mentioned, due to the scarcity of fresh water resources in places like northern Chile, the use of seawater in mineral processing is becoming increasingly important. The direct use of seawater without desalination pre-treatment can be attractive in chalcopyrite leaching due to aggressive nature of chloride solutions and the formation of stable cuprous chloro-complexes. The leaching tests, were investigated at two temperatures (25 °C and 50 °C) using a chalcopyrite concentrate (61.5 wt.%) with a P80= -60 ?m. The leaching tests were conducted in instrumented reactors using double-jacketed glass with a 2000 cm3 volume capacity where each reactor contained 50 g of concentrate in 1000 cm3 of solution with a stirring speed of 400 rpm. The leaching tests continued for 66 and 216 hours where solutions samples were collected periodically and determined using AAS. As preliminary results showed that copper extraction increased with the increase of temperature and acid concentrations, obtaining values close to 80 % of copper recovery.
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