A case study of the separation of copper-gold sulfide ore from pyrite using a novel flotation reagent scheme: Insight from first-principles calculations

Abstract

Due to many problems such as pipe blockage, environmental pollution, and the difficulty of recovering precious metals, caused by extensive use of lime, the conventional program using lime (CaO) as the inhibitor and xanthates (e. g., sodium butylxanthate) (BX) as the collector has become increasingly restricted in use, and lime-free flotation processes are increasingly advocated. In this study, a novel process with Z200 as the collector and pyrogallic acid (PGA) as the inhibitor was innovatively proposed and applied to separate copper-gold sulfide ore and pyrite in Hubei Province, China. In laboratory experiments, this new reagent system achieved a substantially better separation of copper-gold sulfide ore and pyrite than the conventional process program. First-principles calculations based on density functional theory (DFT) were used to understand the separation mechanism of the new reagent scheme. The DFT simulations showed that PGA had a much stronger depression effect on pyrite than chalcopyrite, whereas Z200 exhibited a stronger collecting ability for chalcopyrite than pyrite, which together explains the effectiveness of the new reagent system at the molecular level. This work sheds some new light on the potential of adopting new and eco-friendly reagent schemes in the utilization of mineral resources.

Keywords

novel process / copper-gold sulfide ore / pyrite / separation / DFT simulations

References

[1] ZhouH, ZhangZ-J, OuL-M, et al. . Flotation separation of chalcopyrite from talc using a new depressant carrageenan [J]. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2020, 603: 125274

[2] BilalM, ItoM, KoikeK, et al. . Effects of coarse chalcopyrite on flotation behavior of fine chalcopyrite [J]. Minerals Engineering, 2021, 163106776

[3] WangC-T, LiuR-Q, WuM-R, et al. . Flotation separation of molybdenite from chalcopyrite using rhodanine-3-acetic acid as a novel and effective depressant [J]. Minerals Engineering, 2021, 162106747

[4] LiuD-Z, ZhangG-F, ChenY-F. Investigations on the selective depression of fenugreek gum towards galena and its role in chalcopyrite-galena flotation separation [J]. Minerals Engineering, 2021, 166106886

[5] LiuJ, LiuG-Y, YangX-L, et al. . 6-Hexyl-1, 2, 4, 5-tetrazinane-3-thione: Flotation selectivity and mechanism to copper sulfide mineral [J]. Minerals Engineering, 2020, 152106345

[6] BilalM, ItoM, AkishinoR, et al. . Heterogenous carrier flotation technique for recovering finely ground chalcopyrite particles using coarse pyrite particles as a carrier [J]. Minerals Engineering, 2022, 180107518

[7] LiuD-Z, ZhangG-F, ChenY-F, et al. . Investigations on the utilization of konjac glucomannan in the flotation separation of chalcopyrite from pyrite [J]. Minerals Engineering, 2020, 145106098

[8] ZhangL-M, GaoJ-D, KhosoS A, et al. . A reagent scheme for galena/sphalerite flotation separation: Insights from first-principles calculations [J]. Minerals Engineering, 2021, 167106885

[9] KhosoS A, HuY-H, LiuR-Q, et al. . Selective depression of pyrite with a novel functionally modified biopolymer in a Cu-Fe flotation system [J]. Minerals Engineering, 2019, 13555-63

[10] ZhangX-L, GuX-T, HanY-X, et al. . Flotation of iron ores: A review [J]. Mineral Processing and Extractive Metallurgy Review, 2021, 42(3): 184-212

[11] WuS-H, WangJ-J, TaoL-M, et al. . Selective separation of chalcopyrite from pyrite using an acetylacetone-based lime-free process [J]. Minerals Engineering, 2022, 182: 107584

[12] MitchellT K, NguyenA V, EvansG M. Heterocoagulation of chalcopyrite and pyrite minerals in flotation separation [J]. Advances in Colloid and Interface Science, 2005, 114–115227-237

[13] LinS-Y, HeJ-Y, LiuR-Q, et al. . Depression behavior and mechanism of pyrogallol on bismuthinite flotation [J]. Journal of Cleaner Production, 2021, 281: 125322

[14] LinS-Y, LiuR-Q, SunW, et al. . Pyrogallic acid: A novel depressant for bismuthinite in Mo-Bi sulfide ore flotation [J]. Minerals Engineering, 2019, 131237-240

[15] AgorhomE A, SkinnerW, ZaninM. Post-regrind selective depression of pyrite in pyritic copper-gold flotation using aeration and diethylenetriamine [J]. Minerals Engineering, 2015, 72: 36-46

[16] WeiZ-L, LiY-B, GaoH-M, et al. . New insights into the surface relaxation and oxidation of chalcopyrite exposed to O₂ and H₂O: A first-principles DFT study [J]. Applied Surface Science, 2019, 492: 89-98

[17] ChenJ-H, LongX-H, ChenY. Comparison of multilayer water adsorption on the hydrophobic galena (PbS) and hydrophilic pyrite (FeS₂) surfaces: A DFT study [J]. The Journal of Physical Chemistry C, 2014, 118(22): 11657-11665

[18] CuiW-Y, ZhangJ-J, ChenJ-H. Surface proximity effect of galena and its influence on synergistic adsorption behavior [J]. Applied Surface Science, 2021, 567: 150847

[19] LiuJ, ZengY, LuoD-Q, et al. . Ab initio molecule dynamic simulation of Cu(OH)₂ interaction with sphalerite (1 1 0) surface [J]. Minerals Engineering, 2018, 122176-178

[20] LuoY-J, OuL-M, ChenJ-H, et al. . Effects of defects and impurities on the adsorption of H₂O on smithsonite (101) surfaces: Insight from DFT-D and MD [J]. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2021, 628: 127300

[21] LiuJ, WenS-M, DengJ-S, et al. . DFT study of ethyl xanthate interaction with sphalerite (110) surface in the absence and presence of copper [J]. Applied Surface Science, 2014, 311258-263

[22] FengQ-C, WenS-M, DengJ-S, et al. . DFT study on the interaction between hydrogen sulfide ions and cerussite (110) surface [J]. Applied Surface Science, 2017, 396: 920-925

[23] ChenJ-H, LiY-Q, LanL-H, et al. . Interactions of xanthate with pyrite and galena surfaces in the presence and absence of oxygen [J]. Journal of Industrial and Engineering Chemistry, 2014, 20(1): 268-273

[24] TianM-J, ZhangC-Y, HanH-S, et al. . Effects of the preassembly of benzohydroxamic acid with Fe (III) ions on its adsorption on cassiterite surface [J]. Minerals Engineering, 2018, 127: 32-41

[25] ChenJ-H, WangJ-M, LiY-Q, et al. . Effects of surface spatial structures and electronic properties of chalcopyrite and pyrite on Z-200 selectivity [J]. Minerals Engineering, 2021, 163106803