Kinetics of Pressure Dissolution of Enargite in Sulfate-Oxygen Media

摘要: Enargite (Cu3AsS4) is an increasingly common impurity in Chilean copper concentrates and its presence complicates the conventional treatment of by smelting-converting because environmental risk arsenic emissions to atmosphere. Therefore, recovery from with high content must be carried out nonconventional technologies. Sulfuric acid leaching processes are viable alternatives treat enargite. Hence, this article, pressure enargite sulfuric acid-oxygen system discussed. The was studied at 160 °C 220 partial pressures oxygen 303 1013 kPa. dissolution determined occur as predicted thermodynamics according \( {\text{Cu}}_{3} {\text{AsS}}_{4}+{\text{8.75O}}_{2}+2{\text{.5H}}_{2} {\text{O}}+{\text{2H}}^{+} =3{\text{Cu}}^{2+}+{\text{H}}_{3} {\text{AsO}}_{4} +{\text{4HSO}}^{-}_{4}.\) rate increased substantially increasing temperature. Complete particle size 64 μm obtained 689 kPa 120 minutes. kinetics analyzed using shrinking core model for spherical particles surface chemical control. reaction found 1/3 order respect zero concentration. Activation energy 69 kJ/mol estimated reaction, which a typical value chemically controlled process.