The Influence of Mechanical Activation of Chalcopyrite on the Selective Leaching of Copper by Sulphuric Acid

Base metal sulphides are an important source of various metals. They are typically intergrowth and due to the complex nature of their ores, the hydrometallurgical technique is the very convenient way of extracting the desired component. If it is possible to extract the metal from an ore selectively, the subsequent processing steps become less complicated. Mechanical activation seems to be a favourable pretreatment process for the processing of sulphides prior to the leaching with signifi cantly enhanced metal recoveries reported [1]. This increase in leachability may well be due to a combination of mechanically induced structural defects and chemical reactions involving the mineral and the local environment. Senna [2] analysed the effect of surface area and the structural disordering on the leachability of mechaniIn this paper chalcopyrite, CuFeS2, has been selective leached by H2SO4 as leaching agent (170 g/dm 3) in procedure of hydrometallurgical production of copper. Mechanical activation of the chalcopyrite resulted in mechanochemical surface oxidation as well as in the mineral surface and bulk disordering. Furthermore, the formation of agglomerates during grinding was also occured. Surface changes of the samples using infrared spectroscopy and scanning electron microscopy methods were investigated before and after leaching. The leaching rate, specifi c surface area, structural disorder as well as copper extraction increased with the mechanical activation of mineral.