LAUSR

Abstract Microwave-assisted leaching as a green and efficient method for leaching chalcopyrite has attracted increasing attention. Researchers have actively explored the reasons why microwaves have a positive impact on copper extraction. In this work, X-ray diffraction (XRD), an optical microscope, electron probe micro-analyzer (EPMA) and field emission scanning electron microscope with energy dispersive spectrometer (SEM-EDS) were employed to investigate the surface structure modification of chalcopyrite by microwave during leaching. The modified chalcopyrite had a positive effect on better mineral leachability, higher effective surface for leaching, and the fewer passivation layer. The superior mineral leachability was related to the surplus intermediate products of covellite, while microwave promoted the conversion of chalcopyrite to covellite. In addition, microwave is capable of increasing active sites upon the removal of the passivation layer and the enlargement of the effective reaction surface. This work summarized the relationship between the high copper recovery and the surface structure modification of chalcopyrite systematically.