Flotation Behavior Research Articles

Investigation of serpentine entrainment reduction in pentlandite flotation using eco-friendly sodium alginate in suspension dispersion systems

Magnesium silicates pose severe environmental issues in hydrometallurgical processes. Copper-nickel sulfide ores are the primary source for nickel production, but their increasingly complex properties make separation difficult, causing slimy magnesium silicate minerals to be entrained into the concentrate with the foam, leading to magnesium contamination. Studies have found that sodium alginate (SA), as an environmentally friendly polymer reagent, can effectively inhibit serpentine. This work investigates the effect of SA on the flotation behavior of pentlandite and serpentine in a sodium hexametaphosphate (SHMP) system. Sedimentation tests show that only a low dosage of SA can effectively settle serpentine, while excessive SA disperses serpentine. Flotation tests indicate that SA can further increase the difference in recovery rates between pentlandite and serpentine based on SHMP. Results from artificial mixed ore tests demonstrate that the recovery rate of serpentine decreases from 51.22% to 37.37% with the addition of SA, with minimal impact on the recovery rate of pentlandite. To explain the impact of the SA adsorption process on the mineral states, the following tests and analyses were conducted: TOC and QCM-D results indicate that SA mainly adsorbs onto serpentine, forming rigid adsorption at low dosages and flexible adsorption at high dosages. Zeta potential tests reveal changes in the surface potential of the minerals, explaining the transition from electrostatic attraction to electrostatic repulsion between pentlandite and serpentine. FTIR and XPS results show that SA chemically reacts with the Mg and Si sites on the serpentine surface through its -COO- groups. In summary, in the SHMP system, the use of gel adsorption and the chemical interaction of SA to coagulate and depress serpentine reduces its entrainment into the concentrate, achieving efficient separation of pentlandite and serpentine. However, high dosages of SA do not yield satisfactory results.

Deep insight into the effect of smithsonite particle size on surface heterogeneity and adsorption behavior: A case of fatty acid system

The studies for microfine mineral flotation have focused on the two main directions of increasing the apparent mineral particle size and reducing the bubble size, while little research has been reported on the special surface properties and adsorption mechanisms of mineral particles of different sizes. In this study, sodium oleate was chosen as a typical surfactant. The mechanism of the effect of smithsonite particle size on the heterogeneity and adsorption behavior of the mineral surface was explored in depth. Through microflotation experiments, BET area tests, Washburn contact angle tests, particle agglomeration tests, adsorption tests and inorganic carbon analysis, it was pointed out that the smaller the size of the particles, the greater the surface wettability, and the smaller the density and thickness of adsorbed oleate on the surface. The difficulty of encapsulating the mineral surface with a hydrophobic layer of oleate hydrocarbon chains, as well as suboptimal particle aggregation sizes, are key reasons for the poor flotation behavior of fine smithsonite. Furthermore, the inhomogeneity of active sites and charge distribution of surface components of smithsonite with different sizes was revealed from a microscopic point of view by DRIFT spectroscopic analysis, XPS analysis and zeta potential measurements. As the particle size of smithsonite decreases, the positive charge density on the surface is higher and the hydration tendency is more intense, hindering the adsorption of oleate. This work is expected to guide the full particle size recovery of minerals in the flotation from a novel microscopic point of view.

Impact of grinding media shape on the dissociation characteristics and flotation behavior of coking coal middlings

The effective dissociation of feed materials has a major impact on the mineral flotation recovery performance in the mineral processing field. Coking coal middlings is difficult to be effectively dissociated due to its complex internal gangue distribution characteristics. The aim of this paper is to compare and evaluate the performance of ball versus hexagonal prism media for the coking coal middlings comminution by point contact and line-surface contact. The results of the grinding tests show that hexagonal prism could result in a more uniform coal particle size distribution, less over-grinding and better selective dissociation effect comparing with ball. The results of the particle shape coefficient indicate the hexagonal prism milled product has a sphericity (Rs) of 0.90 and an elongation (EW) of 1.69, which is more slender than the ball milled product (Rs = 0.94, EW = 1.47). Flotation tests showed that the hexagonal prism milled product was more hydrophobic with a wrap angle of 185° compared to the ball milled product at 121°. Meanwhile, the TSI value of the hexagonal prism milled product is 80.500, which is lower than the 82.608 TSI value of the ball milled product, indicating that the flotation system of the hexagonal prism mill product is more stable. Under the same flotation test conditions, the combustible matter recovery rate of the hexagonal prism milled product was 5.08 % higher than that of the ball milled product.

Influence of surface oxidation rate on the flotation of sphalerite and galena inhibited by gum arabic

Differences in the flotation behavior of galena and sphalerite using potassium permanganate (KMnO4) and gum arabic (GA) alone and using a mixture of KMnO4 and GA were investigated. The single mineral flotation tests revealed that when KMnO4 and GA were used individually, galena and sphalerite flotation were inhibited, but the reagent dosages required were large. Sphalerite was strongly inhibited by the addition of a tiny amount of GA after oxidation with KMnO4 while galena was not inhibited under the same conditions. Following oxidation by KMnO4, galena and sphalerite exhibited a significant 83 % difference in flotation recovery when 10 mg/L GA was used, which clearly showed the potential for the combined use of KMnO4 and GA to achieve flotation separation of galena from mixed lead-zinc ores. The inhibitory effect of GA on sphalerite was investigated through a combination of analytical techniques, including Microcalorimetry, Fourier Transform Infrared (FTIR) Spectroscopy, contact angle measurements, X-ray Photoelectron Spectroscopy (XPS), and Scanning Electron Microscopy (SEM) coupled with Energy Dispersive X-ray (EDS) analysis. The results displayed that sphalerite had a much higher oxidation rate than galena, resulting in more oxides and hydroxides. As a result, the sphalerite surface exhibits an increased availability of active sites favorable to GA adsorption, thereby impeding Butyl xanthate (PBX) adsorption. However, the galena surface was able to absorb PBX, resulting in mineral separation.

Improved activation of malachite sulfurization flotation by thiourea's (CS(NH2)2): Performance and mechanism study

In this study, thiourea (CS(NH2)2) was an effective activator for promoting the sulfurization flotation of malachite. The flotation behavior of malachite in the presence of this activator was investigated. Experimental results revealed that thiourea is a superior activator for malachite sulfurization, achieving a recovery rate of over 89 % at appropriate dosages. Thiourea-sulfurized malachite forms a surface layer of copper(I) thiocyanate, which facilitates the reduction of Cu(II) to Cu(I) species, leading to the generation of more Cu(I)−S species. These species adsorb more readily onto the malachite surface compared to Cu(II)−S species. The robust layers consist of SCN¯ ligands that combine with copper(I) complexes to form CuSCN species during sulfurization. This enhances malachite surface sulfurization, resulting in higher flotation recovery. Further analysis using ToF−SIMS, FESEM−EDS, and XPS confirmed that thiourea likely chemisorbs onto the malachite surface through sulfurized malachite. The activation mechanisms and the presence of N-atoms in the XPS spectra verified that N−H, C−N, and Cu−N bonds were chemisorbed and formed on the surface, significantly improving the hydrophobicity of sulfurized malachite. This work has important implications for the future application of thiourea activation in flotation processes and could contribute to developing environmentally friendly solutions to meet consumer demand.

Sources, Performance and Mechanisms of Metal Ions in the Flotation Process of Copper, Lead, and Zinc Ores: A Review

In mineral processing operations, besides target minerals, slurries often contain various metal ions, including common ones with different valence states such as Pb2+, Cu2+, Fe2+, and Fe3+. These metal ions originate from multiple sources during the flotation process, including the dissolution of co-occurring metal minerals during crushing and grinding, the addition of flotation reagents, and the flotation water. Investigators have long recognized that metal ions significantly affect mineral flotation behavior. Due to physical and chemical interactions, some ions in the slurry will interact with target mineral. If these ions form hydrophobic substances on the mineral surface or increase the active sites between the mineral and collectors or sulfide agent, they will have a positive impact on the flotation process. Conversely, if they produce hydrophilic substances or deplete added collectors and sulfides, they negatively impact mineral enrichment. Meanwhile, metal ions can regulate the electrostatic repulsion between reagents and mineral surfaces in the slurry system, which has a certain impact on the flotation results. This study provides a comprehensive overview of the sources of metal ions in flotation, explores their adsorption characteristics on mineral surfaces, and examines their impact on the flotation process. It provides a theoretical basis for improving mineral flotation processes in the presence of metal ions.

A comparison of dry and wet grinding on gold-bearing sulphide ore flotation

This study investigates the hypothesis that dry grinding prior to flotation can mitigate the adverse effects of galvanic interactions, improve the selectivity of gold flotation compared to wet grinding, and offer additional benefits due to water scarcity concerns and high water treatment costs. The effects of dry and wet grinding on the flotation behavior of gold-bearing sulphide ore were studied comparatively in terms of flotation test results and pulp chemistry parameters (pH, Eh, and dissolved oxygen). In addition, flotation tests without conditioning were also conducted following dry grinding in an attempt to minimize water contact further. Results demonstrated that dry grinding increased pulp potentials and dissolved oxygen levels, implying more oxidative conditions. Despite a lower mass pull with dry grinding, flotation recoveries and grades of gold and chalcopyrite were comparable to wet grinding, while dry grinding enhanced pyrite flotation at the rougher stage. Notably, flotation without conditioning effectively rejected pyrite and achieved higher grades for gold and chalcopyrite, indicating selective flotation. Therefore, dry grinding before flotation emerges as a viable alternative for gold and chalcopyrite flotation due to its improved selectivity while carefully optimizing flotation strategies and reagents to maximize recoveries.

Enhanced Flotation Separation of Iron and Silicon with Branched Block Polyethylene Oxide Polypropylene Oxide and Sodium Oleate: Mechanisms and Flotation Behavior

This study explores the strengthening mechanism of the surfactant branched block polyethylene oxide–polypropylene oxide (BB-PEO-PPO) in sodium oleate (NaOL) flotation systems. A comprehensive characterization of BB-PEO-PPO was performed using flotation experiments, contact angle measurements, surface tension analysis, zeta potential measurements, infrared spectroscopy, and foam dynamics assessments. Flotation results showed that the combination of BB-PEO-PPO and NaOL improved iron recovery by 2.71% and reduced the total iron (TFe) grade in tailings by 2.05%, demonstrating a significant enhancement in collecting efficiency. The addition of BB-PEO-PPO effectively reduced foam size and lowered the zeta potential on the surface of activated quartz. At a slurry temperature of 15 °C, BB-PEO-PPO increased the solubility of NaOL radicals, facilitating their chemical adsorption onto activated quartz and improving the hydrophobicity of quartz particles. Notably, the presence of BB-PEO-PPO extended the flotation foam discharge time (D50) by 50% without substantially increasing foam volume, thereby significantly enhancing foam stability.

Assessing the role of seawater in the flotation behavior of chalcopyrite and sphalerite

ABSTRACT In seawater flotation, some chemical properties of seawater affect the flotation separation of chalcopyrite and sphalerite. Using seawater instead of fresh water to separate copper – zinc can save fresh water resources and reduce lime consumption, which has broad prospects in terms of economic and environmental protection. In this paper, the flotation separation behavior of chalcopyrite and sphalerite in seawater was tested and the mechanism was analyzed. As a contrast, the copper grade of concentrate in seawater flotation declined from 23.7% to 22.6%. Meanwhile, the recovery of chalcopyrite declined from 66.2% to 42.8% and the SI value declined from 2.210 to 1.599. With the addition of sodium hexametaphosphate, sodium silicate and EDTA, the SI value increased from 1.599 to 2.176, 2.238 and 2.096, respectively. Nevertheless, when EDTA was excessive, the SI value was only 1.998. This indicated that excessive EDTA is unfavorable to flotation separation of chalcopyrite from sphalerite. Wettability analysis, zeta potential analysis, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, density functional theory calculation and E-DLVO calculation verified the flotation separation behavior and revealed the mechanism.

Study on Dynamic Behavior and Mechanism of Reverse Flotation of Micro-fine Hematite (MFH) Enhanced by Nanobubbles (NBs)

Study on Dynamic Behavior and Mechanism of Reverse Flotation of Micro-fine Hematite (MFH) Enhanced by Nanobubbles (NBs)

Statistical Evaluation of Flotation Behavior of Chalcopyrite in the Presence of SIPX and Acetoacetic Acid n-Octyl Ester as a Novel Collector Blend: A Sustainable Approach

The chalcopyrite deposit in Malanjkhand, India, is the largest copper ore producer in the country. However, its flotation performance has room for improvement. This study used standard flotation experiments using a mechanical flotation cell using a conventional collecting reagent and a collector blend consisting of xanthate and ester. A three-factor, three-level Box-Behnken design was used to statistically evaluate the experimental design. The obtained data were analyzed using an ANOVA, cubic plots, and response surface methods. The goal was to evaluate the effects and interactions of three key process parameters in chalcopyrite flotation: the dosages of sodium silicate (depressant), sodium isopropyl xanthate (collector), and acetoacetic acid n-Octyl ester (co-collector/modifier). The results implied that introducing acetoacetic acid n-Octyl ester along with minor tweaks in the dosages of sodium isopropyl xanthate helped increase copper grades by at least 15%, with good recovery percentiles. Among the three parameters tested, the copper’s grade and recovery were considerably positively influenced by the AoE dosage in the collector blend. Employing 0.006 kg/t sodium silicate and 0.0065 kg/t sodium isopropyl xanthate with 0.005 kg/t of acetoacetic acid n-Octyl ester, an optimum copper recovery of 88.87% could be achieved. However, with a sodium silicate dosage of 0.0048 kg/t, a SIPX dosage of 0.008 kg/t, and an AoE dosage of 0.005 kg/t, optimized copper grade (1.55%) could be achieved, which is a 78.1% increase from the feed sample grade. To validate the expected results, verification experiments were carried out, and the experimental findings were found to be on at par with the statistical model predictions. Furthermore, the calculated SPI value of 0.0000147cap Kg−1 for a global index per resident lies between 0 and 1.

Dodecylphosphonic acid for the separation of spodumene and albite: flotation behavior and adsorption mechanism

Spodumene is an important lithium-bearing mineral, that is associated with albite and difficult to separate because of their similar surface chemical properties. Traditional fatty acid collectors often have issues, such as poor selectivity or weak collector ability, and thus developing efficient spodumene collectors is essential. In this study, the phosphonic acid surfactant dodecylphosphonic acid (DDPA) was first used as a single collector for the flotation separation of spodumene and albite, showing good selectivity and collection performance. Then, separation and adsorption mechanisms were studied using various characterization methods, including diffuse reflectance infrared Fourier transform spectroscopy, total organic carbon adsorption measurements, X-ray photoelectron spectroscopy, and zeta potential tests. Flotation tests showed that the recovery for spodumene can reach approximately 80% through single-mineral flotation under the following conditions: activation without metal ion, neutral pulp pH of 6.5–7.0, and DDPA dosage of 4 × 10−4 mol/L. By contrast, the recovery of albite was only approximately 10%. The recovery for Li2O in the artificial mixed ore test was 75.03%, and the grade was 6.30%. The separation of spodumene and albite was due to the selective adsorption of DDPA on the surface of spodumene, and more DDPA were adsorbed on the surface of spodumene than on albite under the same conditions. Adsorption mechanism analysis indicated that Al and O on the mineral surface were the active sites for DDPA adsorption. Combined with the species distribution, DDPA existed in various forms in different aqueous environments, indicating that DDPA was mainly adsorbed onto the mineral surface through chemisorption and hydrogen bonding. In summary, DDPA can be used as an effective collector for spodumene.

Hydrogen-based mineral phase transformation of bastnaesite: Detailed assessment of physicochemical properties and flotation behavior

Iron-bearing rare earth ores are valuable mineral resources, and the hydrogen-based mineral phase transformation (HMPT) process has significant development potential. In this study, the changes in physicochemical properties and flotation behavior of bastnaesites subjected to HMPT were investigated. The results show that bastnaesite decomposed slowly below 600 °C, but increased roasting temperature and time enhanced the decomposition, resulting in a roasted product with over 85 % rare earth oxide (REO) grade. HMPT also increased the initial pH of the flotation pulp from about 7.5 to 11.0 and increased La and Ce ion concentrations. By increasing the dosage of SHA, flotation recoveries comparable to the raw ore can be achieved. The HMPT process converted bastnaesite to REOF, which formed complex phases such as Ce7O12 and REF3 when exposed to air. This process resulted in significant damage to the particle structure, increased porosity, reduced geometric particle size, and improved wettability. After HMPT, Ce on the particle surface existed predominantly as Ce4+, which formed Ce(OH)4 precipitation during flotation, inhibiting SHA adsorption. The increased particle porosity facilitated deeper SHA penetration and greater adsorption, resulting in higher SHA dosage compared to the raw ore.

Insight into the effect of ultrasonic treatment on surface properties and flotation behavior of chalcopyrite after galvanic corrosion of grinding media and chalcopyrite

Ultrasonic treatment is an effective means to promote chalcopyrite flotation. Chalcopyrite needs to be grinded before flotation production. During the grinding process, galvanic corrosion occurs between chalcopyrite and iron grinding media. Galvanic corrosion significantly affects the efficacy of ultrasonic treatment on chalcopyrite flotation. Nonetheless, there is still a lack of research on ultrasonic treatment of chalcopyrite after galvanic corrosion. In this study, micro-flotation tests, SEM-EDS, TOF-SIMS, XPS, ICP-OES and electrochemical tests were used to study the effects of ultrasonic treatment on the surface properties and flotation behavior of chalcopyrite before and after galvanic corrosion under different ultrasonic conditions and galvanic corrosion conditions. The results show that in the absence of galvanic corrosion, short time and low power ultrasonic treatment can improve chalcopyrite floatability. However, when the chalcopyrite after strong galvanic corrosion is subjected to ultrasonic treatment, the increase of galvanic corrosion temperature, galvanic corrosion time, ultrasound power and ultrasound time result in a marked reduction of the flotation recovery of chalcopyrite. The synergistic effect of ultrasonic and galvanic corrosion significantly inhibits the flotation recovery of chalcopyrite, which may provide a new potential way for the inhibition of sulfide ore in flotation production. The research results are helpful to expand the use range of ultrasonic processing for sulfide mineral pretreatment and flotation, and provide a theoretical reference for the application of ultrasonic treatment in sulfide minerals with galvanic corrosion.

Enhancement mechanism study on the fine hematite flotation by hydrophobic glass microspheres

Previous studies have primarily focused on the use of coarse mineral particles or hydrophobic materials as carriers, whereas this study was the first to investigate the impact of different hydrophobic glass microspheres (HGM-butane, HGM-pentane and HGM-octane) on the flotation behavior of fine hematite, and it revealed the interaction mechanism through Zeta potential and flotation kinetics analysis. The results of micro-flotation tests indicated that the addition of HGM-pentane can increase the flotation recovery of fine hematite from 65.27 % to 84.64 %, which was significantly better than using the collector NaOL alone. Zeta potential results showed that the incorporation of HGM-pentane caused a further negative shift in the surface potential of hematite, enhancing its adsorption capacity with bubbles. Flotation kinetics analysis demonstrated that the addition of HGM-pentane increased the flotation kinetic constant, promoting the flotation rate of fine hematite. This study revealed that the interaction between hydrophobic glass microspheres and fine hematite was primarily through hydrophobic forces and electrostatic attraction, forming a hematite-HGM complex, which in turn improved the flotation recovery of fine hematite. This provided a theoretical basis for the development of efficient flotation reagents and offers new insights into the efficient utilization of fine hematite.

Flotation separation of lithium–ion battery electrodes predicted by a long short-term memory network using data from physicochemical kinetic simulations and experiments

Anode and cathode active materials from spent lithium–ion batteries may be recovered and potentially used in new batteries to promote recycling and resource circulation. Froth flotation was applied to pristine active materials and the black mass obtained from pretreated spent batteries. Flotation kinetics was simulated with the use of computational fluid dynamics and surface chemistry. Bubble surface coverage and entrainment in the flotation kinetics model were selected and optimized by systematic fitting to experimental data. Entrainment influences the recovery and grade of the active materials. The optimized flotation kinetics model was used for generating additional data that, along with the fitted data, were used to train a deep learning neural network. The trained network was validated using anode–cathode and black mass flotation experiments, and its predictions showed a maximum residual error of 0.18 ± 0.11 recovery. The simulation framework was developed into a desktop application that predicts the flotation behavior of active materials. It provides information for estimating results following operational and physicochemical changes and for optimizing flotation processes. Finally, recovered anode active materials from black mass were selected for coin cell tests. The coulombic efficiency of these coin cells was initially lower (86.8 %) than that of cells made with pristine graphite particles (98.4 %).

Investigations on selective flotation separation of quartz from hematite using novel solubility amine as collector: experimental and simulation

Traditional cationic collectors usually have some disadvantages, such as poor selectivity and limited water solubility, which negatively impact flotation efficiency. Thus, a novel cationic collector, 2-(dodecylamino)-2-methyl-1-propanol (DAMP) was developed to enhance the separation efficiency of hematite and quartz. The flotation behavior of DAMP was systematically investigated, and the results indicated that DAMP had good flotation performance and excellent selectivity. Optimal flotation separation of mixed hematite and quartz achieved a concentrate with a TFe grade of 67.79 % and a recovery rate of 91.26 % at a pulp pH of 7.34, using 4.0 mg/L starch and 20.0 mg/L DAMP. Furthermore, the interaction mechanisms between DAMP and the minerals were explored using zeta potential measurements, Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and molecular dynamics (MD) simulation. The findings confirmed that DAMP exhibited superior selectivity compared to DDA, and the adsorption of DAMP on minerals occurred through electrostatic forces and hydrogen bonding interactions.

Study on flotation behavior and mechanism of galena flotation separation from chalcopyrite by sodium periodate depressant

The successful separating galena and chalcopyrite by flotation presents difficulties owing to their analogous surface chemical properties. This study investigated sodium periodate (SP) as a novel depressant for selectively oxidizing and modifying chalcopyrite and galena surfaces, enabling successful flotation separation. In micro-flotation tests were carried out at pH 8.5 and SP concentration of 5 × 10−4 mol/L. The grades of Cu and Pb in the copper concentrate were 27.87 % and 23.13 % with recoveries of 81.22 % and 27.78 %, respectively. SP selectively inhibited galena floatability while preserving chalcopyrite floatability. The selective depression mechanism research of SP in flotation separation process showed that galena surface hydrophobicity was significantly reduced by SP, which in turn prevented the collecting agent from adhering to galena. In the presence of SP, hydrophilic species such as PbSO4 and Pb(OH)2 were generated on the surface of galena, which decreased its ability to float. Conversely, on the chalcopyrite surface, hydrophobic products such as CuS2, CuSn, and S0 were formed, having little effect on its floatability. A model was developed to elucidate the mechanism underlying the selective flotation separation of the chalcopyrite and galena using SP.

Investigation of the flotation behavior and interaction characteristics of micro-fine quartz and magnesite in a dodecylamine system under ultrasonic treatment

Ultrasonic treatment, as an important surface modification method, profoundly affects the flotation behavior of minerals. This study examined the impact of ultrasonic treatment on the surface properties and flotation performance of magnesite and quartz in a dodecylamine (DDA) flotation system. Atomic force microscope detection results revealed that the surface roughness and roughness size of both magnesite and quartz increased after ultrasonic treatment. Flotation tests indicated that the recovery rates of magnesite and quartz were lower after ultrasonic treatment. At pH of 10 and DDA of 75 mg/L, ultrasonic treatment led to a 0.66%, 3.46%, and 0.33% decrease in the flotation recovery rates for three different magnesite particle sizes. Following ultrasonic processing, the flotation recovery rates for three different quartz particle sizes decreased by 8.48%, 30.76%, and 43.69%, in that order. X-ray photoelectron spectroscopy detection results showed an increased presence of characteristic Mg and Si sites on the surfaces of magnesite and quartz following ultrasonic treatment. DDA acted on the surfaces of the two minerals through electrostatic adsorption and hydrogen bonding adsorption and repelled the flotation of minerals owing to the same charge as characteristic sites, thereby reducing flotation recovery. Adsorption capacity tests and contact angle measurements demonstrated a decrease in DDA adsorption and contact angle on the surfaces of magnesite and quartz after ultrasonic treatment, explaining the reduced floatability. Extended Derjaguin–Landau–Verwey–Overbeek theoretical calculations indicated that before ultrasonic treatment, there was a repulsive energy between magnesite and fine-grained quartz particles. After ultrasonic treatment, the interaction energy between magnesite and fine quartz particles is mutual attraction.

Effect of Ni substitution atom on electronic properties and surface oxidation of pyrrhotite

The crystal and surface electronic properties of minerals are fundamentally linked to their flotation behavior. To investigate the effects of Ni substitution for Fe in pyrrhotite on the crystal and surface properties, as well as its oxidation by O2, density functional theory (DFT) was employed to analyze these changes at a microscopic level in both monoclinic and hexagonal pyrrhotite. The findings reveal that Ni substitution increases electron activity in monoclinic pyrrhotite, enhancing its resistance to oxidation by O2, while also strengthening the interaction between Ni-substituted monoclinic pyrrhotite and butyl xanthate. Conversely, in hexagonal pyrrhotite, Ni substitution enhances electron stability but makes it more susceptible to oxidation by O2 and weakens its interaction with butyl xanthate. Understanding the electronic properties and interaction mechanisms of Ni-substituted pyrrhotite with O2 is crucial for elucidating the surface oxidation mechanisms of pyrrhotite. This research offers insights and guidance for optimizing pyrrhotite flotation processes.