Resources Recycling ISSN:2765-3439(Print) 2765-3447(Online) 자원리싸이클링

When the pressure leaching process of chalcopyrite is operated in the low and medium temperature range of 90℃~150℃, the sulfur component in chalcopyrite is converted to elemental sulfur, which suppresses the leaching of copper. In the present study, the copper leaching rate was improved by adding chloride ions and surfactants during the medium-temperature pressure leaching process at 150℃. Using the autoclave equipped with a 2L reactor made of titanium, a pressure leach tests were conducted for 180 min using 100g of chalcopyrite concentrate with D₉₀ particle sizes of 10μm and 45μm in 5g/L and 50g/L sulfuric acid solutions. At 50g/L sulfuric acid solution without chloride ion and surfactant, when a sample with a D₉₀ particle size of 45μm was used, the copper leaching efficiency after 180 min was 48%. As a result of leaching by adding 12g/L of chloride ions such as HCl, CuCl₂, and NaCl, the leaching efficiencies increased to 96% and 97%, respectively, by adding HCl and CuCl₂. As a result of a pressure leaching tests by adding surfactants of SLS (Sodium lignosulfonate) and CLS (calcium lignosulfonate), the leaching efficiency was over 99%. Consequentially, copper leaching efficiency increased when chloride ions and surfactants were added in 50g/L sulfuric acid solution.