Underlying synergistic collection mechanism of an emerging mixed reagent scheme in chalcopyrite flotation

Effective collectors are essential for the flotation of copper sulphide resources. In this work, we prepared a novel surfactant containing C-O-C groups, O,O'-bis(2-butoxyethyl) ammonium dithiophosphate (BEAT), and mixed it with O-isopropyl-N-ethyl thionocarbamate (IPETC) as an emerging reagent scheme for effi-ciently improving the flotation recovery of chalcopyrite. Foaming performance tests revealed that BEAT possessed a stronger foaming ability and foam stability than methyl isobutyl carbinol (MIBC). Micro-flotation results indicated that a significant improvement of chalcopyrite flotation recovery of 92.43% was achieved when mixed IPETC/BEAT collectors (BEAT optimal molar fraction of 60%) of 4 x 10-5- mol/L at pH 7.0-7.5 were employed. Bench-flotation results of copper sulphide ores showed that com-pared with IPETC + MIBC (30 g/t + 36 g/t) or BEAT (30 g/t) alone reagent system, a smaller amount of mixed IPETC/BEAT collectors (only 20 g/t) scheme was able to obtain higher Cu recovery and Cu grade. Surface tension results implied that the mixtures provided higher surface activity than individual IPETC, thus exhibiting superior foaming properties and better water solubility. Wettability results sug-gested that mixed collectors possessed stronger hydrophobicity and superior selectivity towards chal-copyrite against pyrite than single collector. FTIR results demonstrated that mixed collectors were chemically involved with the chalcopyrite surface through co-adsorption. Intermolecular interaction parameter computation confirmed the positive synergistic effect of mixed collectors.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

In this study, a novel reagent system consisting of IPETC and BEAT collectors was developed to improve the flotation recovery of chalcopyrite. The results showed that the mixed collectors exhibited superior foaming properties, better water solubility, stronger hydrophobicity, and greater selectivity towards chalcopyrite. The interaction between the mixed collectors and chalcopyrite surface was chemically involved, leading to a positive synergistic effect.