Homogenization phenomena of surface components of chalcopyrite and sphalerite during grinding processing

The selective flotation separation of chalcopyrite and sphalerite has been a general industrial challenge. In this study, we studied the occurrence of surface homogenization of chalcopyrite and sphalerite during grinding by using time of flight secondary ion mass spectrometry analysis (ToF-SIMS), principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA). The results showed that the surface compositions of chalcopyrite and sphalerite became more similar after simultaneous grinding. The copper ions that released from the chalcopyrite were more easily adsorbed on to the sphalerite surface than iron ions, conversely, the zinc ions that dissolved from the sphalerite were poorly adsorbed by the chalcopyrite surface. PCA and OPLS-DA were used to confirm the differences in surface compositions of chalcopyrite and sphalerite, and the results showed that after simultaneous grinding, the sphalerite surface compositions were converted to chalcopyrite, and the surface compositions of chalcopyrite also changed.