Flotation Separation of Chalcopyrite from Pyrite and Sphalerite Using a Novel Collector: an Experimental and Mechanism Investigation

In this paper, a new collector, named O-isobutyl-N-allyl thionocarbamate (IBATC), was synthesized, and the structure was characterized by Fourier Transform Infrared Spectrometer (FTIR) and 1H NMR, 13C NMR analysis. The collection performance of IBATC was evaluated by flotation tests and interaction mechanism was investigated by means of adsorption amount, zeta potential measurements, FTIR, X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculation. The flotation tests results proved that IBATC was inclined to collect chalcopyrite compared with pyrite and sphalerite. Especially in the pH range of 9.5-10 and IBATC concentrate of 30-40 mg/L, the recovery of chalcopyrite exhibited more than 80 %. The adsorption amount and zeta potential measurements showed that IBATC had a greater orientation to chalcopyrite. FTIR and XPS analysis demonstrated IBATC chemically adsorbed on chalcopyrite surface, whereas physically adsorbed on pyrite and sphalerite. Further, DFT calculation of the interaction between IBATC and chalcopyrite proved that S atom of IBATC donated electrons to Cu sites on chalcopyrite surface and the adsorption energy was -19.45 kcal/mol, referring to an exothermic reaction. As a result, IBATC showed great capacity for the separation flotation of chalcopyrite, pyrite and sphalerite.