Predicting the surface chemistry contribution to the flotation recovery of chalcopyrite by ToF-SIMS

In flotation, the surface chemistry of the minerals plays a crucial role in the selectivity and recovery of valuable minerals. Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) surface analysis is used in this study to investigate the impact of surface chemistry on the flotation of chalcopyrite with dithiophosphate collector. The ToF-SIMS data corresponding to concentrate and tail particles were statistically analysed employing a combination of multivariate statistical techniques – principal components analysis and discriminant analysis – to identify the surface species that are differential in the flotation of chalcopyrite. Two models were developed to predict the concentrate and tail deportment of particles, one targeting fine and intermediate particle sizes and the other for the coarse particle size. These models were tested using cross-validation and the results showed good prediction accuracy, 88% for fine and intermediate particles and 77% for coarse particles. The models were further tested on feed samples and the results show the developed models can be used as a predictive tool that estimates the maximum recovery expected based on the surface chemistry of particles, as evidenced by ToF-SIMS, under given hydrodynamic conditions.