Mechanistic insights into flotation separation of galena and chalcopyrite with polymaleic acid as Pb-affinity depressant: Experiments and MD simulations

Utilization of novel and highly efficient organic depressants in separation of various minerals in flotation is always a research hotspot. Herein, polymaleic acid (PMA) was utilized as an eco-friendly depressant with high affinity for lead to effectively separate chalcopyrite from galena via the flotation method. Flotation trials showed that PMA, added at low dosages, could considerably depress galena, while chalcopyrite was minimally affected, thereby achieving the separation of both minerals. Adsorption tests indicated that PMA strongly and selectively adsorbed on galena than on chalcopyrite, which significantly reduced the reactive activity of xanthate on galena. These findings were supported by contact angle measurements. Surface properties investigations also corroborated the stronger adsorption of PMA observed on galena. Molecular dynamic simulations suggested that the introduction of PMA into an aqueous system resulted in the accumulation of water molecules on galena. Simultaneously, the adsorption strength of PMA on galena increased during the interaction process between PMA and galena. These effects altered the surface characteristics of galena and increased its surface hydrophilicity. The present work provides mechanistic insights into the separation of metallic sulfide minerals in the presence of organic acid via the flotation method.