Activity: Talks and presentations › Conference presentations
Due to its semiconductor properties, the world’s most abundant copper mineral, chalcopyrite (CuFeS<SUB>2</SUB>), is refractory with respect to atmospheric leaching using traditional acidic ferric sulfate lixiviants. FLSmidth<SUP>®</SUP> has developed a novel Rapid Oxidative Leach (ROL) process that (a) manipulates the lattice and (b) mechano-chemically processes chalcopyrite with a Stirred Media Reactor (SMRt). This combination yields the benefit of increasing chemical reactivity and dissolution kinetics. By reducing surface passivation, this process is typically able to achieve copper recoveries exceeding 95% in under 6-8 hours. An important factor contributing to this extraordinary performance is a mineral preconditioning step, which uses 0.1-5 mol% of copper(II) to dope the lattice and thereby "activate" chalcopyrite. Previously, we reported the relationship between doping and deformation of the chalcopyrite lattice using electron microscopy. Now, we draw further insights into the electrochemical properties of the activated chalcopyrite particles through a variety of surface spectroscopy studies.