A method for studying the interaction mechanism between different mineral particles in a flotation process

Abstract

The application discloses a research method for interaction mechanism between different mineral particles in a flotation process, overcomes the problem that a product layer formed by chemical reactions in the flotation process is non-uniform and thin, and different types of minerals after reactions cannot be accurately distinguished, and based on the advantage, by combining macro and micro in-situ detection with theoretical calculation, a correlation mechanism of each factor (adding different reagents or passing in air) in the flotation process, product on the surface of the ore and interaction force between the ores, and agglomeration and dispersion behavior between the ore particles is established, so as to provide theoretical guidance for realizing efficient separation of complex ores by regulating the agglomeration and dispersion behavior between the mineral particles through regulating each factor (adding different reagents or passing in air) in the flotation process.

Description

Technical Field

[0001] This invention relates to the field of mineral processing engineering, and specifically to a research method for the interaction mechanism between different mineral particles during flotation. Background Technology

[0002] In complex flotation systems of polymetallic or oxide or sulfide ores with high content of fine-grained slime, direct physical adsorption such as slime covering and heterogeneous agglomeration or indirect chemical adsorption and homogenization effects (cross-activation and inhibition of solution ions on different mineral surfaces) can occur between different types of mineral particles (Yin Wanzhong, Tang Yuan. Interactions in mineral flotation process [J]. Mineral Conservation and Utilization, 2018(3): 55-60). Fine-grained gangue minerals covering the surface of useful minerals reduce the recovery rate of flotation concentrate (Chinese patent application CN119565767A); heterogeneous agglomeration among minerals reduces the enrichment ratio of flotation concentrate (Yin WZ, Tang Y. Interactive effect of minerals on complexore flotation: A brief review, Int. J. Miner. Metall. Mater, 27(2020), No, 5,pp, 571-583); the homogenization effect among different types of mineral particles can significantly change the surface chemical state of minerals, which may cause the activation and flotation of gangue minerals (Yin Wanzhong, Tang Yuan. Interactive effects in mineral flotation process [J]. Mineral Conservation and Utilization, 2018(3): 55–60), thus significantly affecting the ore flotation separation effect. In summary, research on the types of interactions between different minerals (agglomeration, dispersion, or homogenization effects) and their driving forces is crucial for revealing the causes of deteriorating flotation performance and for developing targeted processes such as dispersion, selective inhibition, or desliming to improve ore separation. Therefore, establishing reliable research methods for the interaction mechanisms between different mineral particles is key to accurately and efficiently improving the flotation separation performance of complex ores.

[0003] The research methods for the interaction mechanism between different mineral particles can be broadly classified into two types in the current literature: First, macroscopic and microscopic detection, such as sedimentation experiments to observe agglomeration or dispersion (Chinese patent application CN107149988A), contact angle measurement (Fan Guixia. Study on interface control in flotation of ilmenite flocs [D]. China University of Mining and Technology, 2015), Zeta surface potential analysis, and AFM colloidal probe measurement of intermineral forces (Chinese patent application CN121721318A), etc. However, the above methods are affected by the superposition of factors such as particle size, stirring intensity, and air introduction, resulting in an uneven and thin (nanoscale) surface layer, making it difficult to accurately distinguish different types of minerals at different reaction stages. Therefore, it is difficult to measure the influence of the interaction between different minerals on the flotation recovery effect independently; Second, theoretical calculation, such as density functional theory (DFT) (Wu Zhiqiang, Lu Xiayi, Li Zheng, et al. Research progress on mineral flotation theory based on quantum chemistry and machine learning [J]. Mineral Resources Protection and Utilization, 2026, 46(2): 23-42) and DLVO (Derjaguin-Landau-Verwey-Overbeek) theoretical calculations (Chinese patent application CN122135798A), etc., but due to the large amount of DFT calculation, it usually only considers ideal crystal planes and ignores the influence of actual factors such as defects, impurities, and surface reconstruction (Hao Haiqing, Li Lixia, Zhang Chen, et al. Application of classical molecular dynamics simulation in mineral flotation research [J]. Mineral Resources Conservation and Utilization, 2018 (3): 9-16), and its calculation process strongly depends on the accuracy of microscopic detection results. Therefore, it can usually only be used as auxiliary evidence for conclusions. Similarly, due to the difficulty in accurately distinguishing different types of minerals at different reaction stages and the difficulty in obtaining parameters such as the potential and contact angle of different types of minerals under different reaction states, the DLVO theoretical calculation results are only semi-quantitative predictions. In summary, the flotation process is influenced by numerous factors, with modifiers, collectors, and air introduction significantly affecting the interactions between different ores. Furthermore, the uneven and thin (nanoscale) product layer formed on the mineral surface during flotation, and the difficulty in accurately distinguishing different minerals at different reaction stages, have led existing research methods to focus primarily on macroscopic and microscopic detection or theoretical calculations. This results in less convincing conclusions and a failure to qualitatively establish the correlation between various influencing factors (modifiers, collectors, or air introduction) and mineral surface products, inter-particle interactions, and particle aggregation and dispersion behavior using a combination of macroscopic and microscopic detection and theoretical calculations. Consequently, reliable theoretical guidance for efficient ore separation is lacking. Therefore, research methods for understanding the interaction mechanisms between different mineral particles during flotation require further optimization. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention aims to provide a research method for the interaction mechanism between different mineral particles during the flotation process.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for studying the interaction mechanism between different mineral particles during flotation includes the following steps: S1. Pure mineral 1 and pure mineral 2 to be studied are prepared in advance. Pure mineral 1 and pure mineral 2 have different particle sizes. The prepared pure mineral 1 and pure mineral 2 are stored in two sample bags for later use. After the sample bags are evacuated, they are placed in a desiccator filled with nitrogen. S2. Mix pure mineral 1 and pure mineral 2 evenly to prepare a sample for later use; S3. After mixing the spare sample obtained in step S2 with water, put it into a stirrer equipped with a focused beam reflectance measuring instrument and a particle video microscope. During the stirring process, the average chord length of the mixed mineral particles at different reaction times is measured using the focused beam reflectance measuring instrument. After the average chord length of the particles stabilizes, the morphology of the current mixed mineral particles is obtained using the particle video microscope. A set amount of the current mixed mineral particles is taken as the sample of control group 1 while stirring. S4. Add the modifier to the remaining mixed mineral particle system in step S3, and after the set time, obtain the average chord length and morphology of the current mixed mineral particles. Take a set amount of the current mixed mineral particles as the sample of experimental group 1 while stirring. S5. Add the collector to the remaining mixed mineral particle system in step S4. After the set time, obtain the average chord length and morphology of the current mixed mineral particles. Take a set amount of the current mixed mineral particles as the sample of experimental group 2 while stirring. S6. The mixed mineral samples of control group 1 and experimental groups 1 and 2 were sieved separately. Due to the difference in particle size between pure mineral 1 and pure mineral 2, the two mineral samples that were uniformly mixed after the reaction in control group 1 and experimental groups 1 and 2 were re-separated into 6 groups of pure mineral samples representing different reaction stages, including: pure mineral 1 and pure mineral 2 in control group 1; pure mineral 1 and pure mineral 2 in experimental group 1; and pure mineral 1 and pure mineral 2 in experimental group 2. The 6 groups of pure mineral samples obtained by sieving were stored in different sample bags after vacuuming, and each sample bag was placed in a desiccator filled with nitrogen for later use. S7. Measure the Zeta potential and powder contact angle of the six groups of pure mineral samples obtained in step S6 using a surface potential meter and a contact angle meter, respectively; determine the species fragments and proportions of the surface products of the six groups of pure mineral samples obtained in step S6 using time-of-flight secondary ion mass spectrometry; measure the organic and inorganic spectra of the surface products of the six groups of pure mineral samples obtained in step S6 using infrared spectroscopy and Raman spectroscopy, respectively, and combine the species fragment and proportion measurement results to preliminarily determine the types and quantities of surface products of the six groups of pure mineral samples obtained in step S6; measure the elemental valence states and proportions of the surface products of the six groups of pure mineral samples obtained in step S6 using X-ray photoelectron spectroscopy to further clarify the types and quantities of surface products of the six groups of pure mineral samples. S8. Using the extended DLVO theory combined with Zeta potential and powder contact angle measurement results, the interaction forces between pure mineral 1 and pure mineral 2 in control group 1, between pure mineral 1 and pure mineral 2 in experimental group 1, and between pure mineral 1 and pure mineral 2 in experimental group 2 were calculated. The changes in the interaction forces between pure mineral 1 and pure mineral 2 at different reaction stages were obtained. Combined with the in-situ measurement results of focused beam reflectance measurement instrument and particle video microscope at different reaction stages, the correlation mechanism between the addition of modifiers and collectors in the flotation process and the surface products of ore, the interaction forces between mineral particles, and the agglomeration or dispersion behavior of mineral particles was obtained. This provides theoretical guidance for controlling the agglomeration and dispersion behavior of mineral particles by adding modifiers and collectors in the flotation process to achieve efficient separation between useful minerals and gangue mineral particles.

[0006] Further, in step S1, the particle sizes of pure mineral 1 and pure mineral 2 are 58-75μm and 25-38μm, respectively; in step S6, the mixed mineral samples of control group 1 and experimental group 1 and experimental group 2 are sieved using a 325-mesh sieve.

[0007] Further, in step S2, the total amount of pure mineral 1 and pure mineral 2 is 90-100g, and the mass ratio of pure mineral 1 to pure mineral 2 is 1:1-1:5; in step S3, the mass ratio of the spare sample to water is 1:1-1:2.

[0008] Furthermore, in step S3, the stirrer speed is maintained at 300-350 r / min.

[0009] Furthermore, in steps S4 and S5, the reaction time of the reagents is set to 2-3 minutes, consistent with the industrial flotation production process.

[0010] Furthermore, in step S8, the total energy of the interactions between mineral particles... Mainly includes van der Waals energy Electrostatic interaction energy between particles Hydrophobic interaction energy The expression is as follows: ; The formula for calculating the van der Waals energy is as follows: ; in, The calculation formula is: ; and These are the Hamaker constants for mineral 1 and mineral 2 in their respective media. It is the Hamaker constant of water under vacuum conditions, with a value of 4 × 10⁻⁶. -20 J; The Hamaker constant is calculated using the following equation: ; Electrostatic interaction energy between fine particles The calculation formula is as follows: ; ; ; in, It is the absolute permittivity in vacuum; is the dielectric constant of the water medium; and , respectively, are the surface potentials of mineral 1 and mineral 2, expressed as measured Zeta potential values ​​in V; H is the interaction distance between the two fine particles in nm; The length of Debye; Hydrophobic interactions between fine particles The calculation formula is as follows: ; Attenuation length The value of is 1 nm; H is the interaction distance between the two fine particles; This represents the minimum contact distance between mineral surfaces under equilibrium conditions. The energy constant for the interaction between polar interfaces is determined by the following equation: ; in, and These are the surface tension parameters for mineral 1, mineral 2, and the medium, respectively. For the water medium, = =25.5×10 -3 J / m 2 ; and Calculate using the following formula: ; in, Represents the surface energy of a liquid. Indicates the nonpolar / dispersive component of the liquid; Represents the nonpolar / dispersive component of a solid; Represents the Lewis acid parameter of a solid; This indicates the Lewis acid parameter of the liquid; The contact angle between liquid and solid surfaces, and the mineral's and The contact angle was obtained by measuring the contact angle in two solutions with known surface tensions.

[0011] Furthermore, The value is 8.854 × 10 -12 C -2 J -1 m -1 ; The value is 78.5 C. -2 J -1 m -1 ; The value for mixed mineral particles is 0.104 × 10⁻⁶. -9 m -1 ; The value is 0.15 nm; when water is the medium: 72.8×10 -3 J / m 2 , 21.8×10 -3 J / m 2 When glycerol is used as the medium, 6×10 -3 J / m 2 , 34×10 -3 J / m 2 , 3.92×10 -3 J / m 2 and It is 57.4×10 -3 J / m 2 .

[0012] The beneficial effects of this invention are as follows: It is widely acknowledged in the industry that the interaction between different mineral particles during the flotation process significantly affects the mineral flotation separation effect. However, due to the uneven and thin (nanoscale) product layer formed by the chemical reactions during flotation, it is impossible to accurately distinguish between different types of minerals at different reaction stages. This makes conventional detection methods unable to qualitatively characterize the products and interaction forces on the surfaces of different types of minerals at different reaction stages. Furthermore, due to these limitations, existing research methods mostly focus on macroscopic and microscopic detection evidence or theoretical calculations, failing to combine the two. This lack of comprehensive and convincing evidence for elucidating the interaction mechanism of different mineral particles during flotation prevents the development of targeted technical guidance for optimizing flotation indicators from a theoretical research perspective. Therefore, it is necessary to develop suitable research methods to enhance the uniformity and thickness of the product layer on the surface of different types of minerals, accurately distinguish between different types of minerals at different reaction stages, and combine macroscopic and microscopic detection with theoretical calculations to provide comprehensive and convincing evidence. The research method determined in this invention is developed based on this principle and under extensive practical conditions.

[0013] To address the challenge of uneven and thin product layers formed on mineral surfaces during flotation due to chemical reactions, we first prepared different types of mineral particles with defined particle size ranges using Taylor standard sieves. This defined particle size range ensured the uniformity of the sample particle size, and the uniform particle size ensured that the products generated by chemical reactions on the surface of the same type of mineral particles were relatively uniform. The significant differences in the defined particle size ranges between different types of minerals reflect the objective fact that different minerals exhibit varying degrees of liberation during grinding-flotation. Furthermore, finer-sized minerals have a larger specific surface area and undergo deeper chemical reactions, increasing the quantity and thickness of products on the sample surface.

[0014] To address the challenge of accurately distinguishing different types of mineral particles at different reaction stages after a chemical reaction, this invention, while limiting the particle size of different types of minerals during sample preparation, utilizes a 325-mesh (approximately 45 μm) Taylor standard sieve to re-physically classify the mixed minerals in the control and experimental groups after the chemical reaction into pure mineral 1 and pure mineral 2. Even if agglomeration occurs during the reaction process, it is relatively easy to break up the loose flocs through the Taylor standard sieve of this mesh size, without significantly damaging the generated surface product layer (the limited particle size range ensures that the chemical reaction is relatively uniform at various points on the mineral, and even if some reaction products are broken up during the sieving process, most of the reaction products are still retained).

[0015] Addressing the challenge that existing research methods fail to combine macroscopic and microscopic detection evidence with theoretical calculations, resulting in unconvincing conclusions, this invention employs a focused beam reflectance meter and particle video microscopy to in-situ detect the aggregation and dispersion behavior of different minerals during flotation. Time-of-flight secondary ion mass spectrometry (TOF-MS / MS) determines the species fragments and proportions of surface products from different types of pure mineral samples at different reaction stages. Infrared and Raman spectroscopy preliminarily determine the types and quantities of surface products from different types of pure minerals at different reaction stages. X-ray photoelectron spectroscopy further clarifies the types and quantities of surface products from different types of pure minerals at different reaction stages. This allows for a more comprehensive understanding of the species fragments on the surface of mineral particles during flotation. These changes are related to the aggregation and dispersion behavior of particles. Ultimately, calculations using the extended DLVO theory reveal the main driving forces behind mineral aggregation and dispersion during flotation. This research approach, combining macroscopic and microscopic in-situ detection with theoretical calculations, establishes the correlation mechanism between various factors in the flotation process (addition of reagents or introduction of air) and the interaction forces between different types of mineral surface products and ore particles at different reaction stages, as well as the aggregation and dispersion behavior of ore particles. This provides theoretical guidance for controlling the aggregation and dispersion behavior of mineral particles by regulating various factors in the flotation process (addition of different reagents or introduction of air), thereby achieving accurate and efficient separation of complex ores.

[0016] As can be seen from the above, the research method proposed in this invention overcomes the problem that the product layer formed by the chemical reaction during the flotation process is uneven and thin, making it impossible to accurately distinguish different types of minerals after the reaction. Based on this advantage, by combining macroscopic and microscopic in-situ detection with theoretical calculations, a correlation mechanism is established between various factors in the flotation process (addition of different reagents or introduction of air) and the interaction forces between ore surface products and ore particles, as well as the agglomeration and dispersion behavior of ore particles. This provides theoretical guidance for controlling the agglomeration and dispersion behavior of mineral particles by regulating various factors in the flotation process (addition of different reagents or introduction of air), thereby achieving efficient separation of complex ores. Attached Figure Description

[0017] Figure 1 This is a flowchart of a method according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the FBRM measurement results in an embodiment of the present invention; Figure 3 This is a schematic diagram of the PVM measurement results in an embodiment of the present invention; Figure 4 This is a schematic diagram of the secondary ion mass spectrometry test results in an embodiment of the present invention; Figure 5 This is a schematic diagram of the infrared spectroscopy test results in an embodiment of the present invention; Figure 6 This is a schematic diagram of the Raman spectroscopy test results in an embodiment of the present invention; Figure 7 This is a schematic diagram of the X-ray photoelectron spectroscopy Fe 2p test results in an embodiment of the present invention; Figure 8 This is a schematic diagram of the X-ray photoelectron spectroscopy O 1s test results in an embodiment of the present invention; Figure 9 This is a schematic diagram of the X-ray photoelectron spectroscopy Mg 1s test results in an embodiment of the present invention; Figure 10 This is a schematic diagram of the Ca 2p test results of X-ray photoelectron spectroscopy in an embodiment of the present invention; Figure 11 This is a schematic diagram showing the results of the E-DLVO theoretical calculation of the interaction force between pure pyrite and pure dolomite in control group 1 in an embodiment of the present invention; Figure 12 This is a schematic diagram of the interaction force results between pure pyrite and pure dolomite in Experiment 1 of the E-DLVO theoretical calculation in this embodiment of the invention; Figure 13 This is a schematic diagram of the interaction mechanism between mineral particles obtained in the method of this embodiment of the invention. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings. It should be noted that this embodiment is based on the present technical solution and provides detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to this embodiment.

[0019] A difficult-to-process, low-grade Carlin-type gold ore (sulfide ore) has an Au grade of 1.18 g / t, an Fe grade of 2.38%, a Ca grade of 10.45%, and a Mg grade of 5.37%. The ore characteristics are: (1) the gold in the ore is hosted in pyrite in the form of fine grains, which is easily oxidized; (2) the gangue minerals are mainly dolomite. When conventional flotation methods are used to process this Carlin-type gold ore, the separation effect is poor (enrichment ratio is only about 2), the Au recovery rate is <80%, the mechanism of the interaction between minerals affecting the flotation recovery effect is unclear, and the influencing factors are investigated one by one by the controlled variable method at the production site, with very little effect and extremely poor flotation economy.

[0020] This embodiment employs a research method based on the interaction mechanism between different mineral particles during the flotation process to study the mechanism by which the interaction between minerals affects the flotation recovery effect of the aforementioned difficult-to-process low-grade Carlin-type gold ore. Figure 1 As shown, it includes the following steps: S1. Pyrite (pure mineral 1, purity >90%) with a particle size of 58-75μm and dolomite (pure mineral 2, purity >90%) with a particle size of 25-38μm were prepared using Taylor standard sieves. Pure mineral 1 and pure mineral 2 were stored in two sample bags respectively. After vacuuming the two sample bags, they were placed in a desiccator filled with nitrogen to prevent oxidation by air and avoid sample contamination.

[0021] S2. Mix pure mineral 1 and pure mineral 2 evenly at a mass ratio of 1:5 to prepare a spare sample. The total amount of the spare sample is 100g.

[0022] S3. Mix the prepared sample with water at a mass ratio of 1:2 and place it in a stirrer equipped with a focused beam reflectance meter (FBRM) and a particle video microscope (PVM) (stirrer speed is 300 r / min). Use the FBRM to observe the average chord length of the mixed mineral particles at different reaction times (reflecting the average particle size of the mixed mineral particles at this moment). After the average chord length of the particles stabilizes, use the PVM to capture the morphology of the mixed mineral particles, and take 50 mL of the current mixed mineral particles as the sample of control group 1 while stirring.

[0023] S4. Using a peristaltic pump, add 2 g / L of H2O2 as a modifier to the remaining mixed mineral particle system in step S3 to simulate the mineral oxidation reaction. After 2 mins, obtain the average chord length and morphology of the mixed mineral particles. Take 50 mL of the current mixed mineral particles as the sample of experimental group 1 while stirring.

[0024] S5. Add 2 g / L of xanthate, the collector, to the remaining mixed mineral particle system in step S4 using a peristaltic pump. After 2 mins, obtain the average chord length and morphology of the current mixed mineral particles. Take 50 mL of the current mixed mineral particles as the sample of experimental group 2 while stirring.

[0025] S6. The homogeneous samples taken from control group 1, experimental group 1, and experimental group 2 were sieved through a 325-mesh (approximately 45 μm) sieve to form six groups of pure mineral samples representing different types of minerals at different reaction stages: pure mineral 1 and pure mineral 2 in control group 1; pure mineral 1 and pure mineral 2 in experimental group 1; and pure mineral 1 and pure mineral 2 in experimental group 2. The six groups of pure mineral samples were stored separately in vacuum-sealed sample bags, and each sample bag was placed in a desiccator filled with nitrogen for later use. Comparative analysis of these six groups of pure mineral samples representing different reaction stages was used to distinguish the effects of various factors (addition of modifiers or collectors) on the interactions between minerals in the conventional flotation process.

[0026] S7. The surface potential and powder contact angle of the above six groups of pure mineral samples were measured using a Zeta potential meter and a powder contact angle meter. The species fragments and proportions of the surface products of the pure mineral samples in control group 1 and experimental group 1 were determined using time-of-flight secondary ion mass spectrometry (actual measurement results showed that the macroscopic appearance (agglomeration) of the samples in experimental group 1 and experimental group 2 were similar, and there were no significant differences in other detections. Therefore, this embodiment does not present the test results in experimental group 2 to avoid misleading. Therefore, in the subsequent measurement process, only the results in control group 1 and experimental group 1 are emphasized). The organic and inorganic spectra of the surface of the pure mineral samples in control group 1 and experimental group 1 were measured using infrared spectroscopy and Raman spectroscopy. Combined with the above species fragment and proportion measurement results, the types and quantities of different types of pure mineral surface products at different reaction stages were preliminarily determined. The elemental valence state and proportion information of the surface products of the pure mineral samples in control group 1 and experimental group 1 were measured using X-ray photoelectron spectroscopy to further determine the types and quantities of different types of pure mineral surface products at different reaction stages.

[0027] S8. Using the extended DLVO theory combined with Zeta potential and contact angle measurements, the changes in the interaction forces between pure mineral 1 and pure mineral 2 in control group 1 and between pure mineral 1 and pure mineral 2 in experimental group 1 were calculated. Combined with the in-situ measurement results of FBRM and PVM at different reaction stages, the correlation between various factors (addition of modifiers or collectors) in the flotation process and ore surface products, the interaction forces between mineral particles, and the agglomeration or dispersion behavior of mineral particles was established. This provides theoretical guidance for controlling the agglomeration and dispersion behavior of mineral particles by regulating various factors (addition of modifiers or collectors) in the flotation process to achieve efficient separation between useful minerals and gangue mineral particles.

[0028] The process by which the interaction mechanism between minerals was obtained through the above research method in this embodiment is as follows: Figure 2 The FBRM measurement results showed that during the flotation of pyrite and dolomite, after the oxidation reaction, obvious agglomeration occurred between particles (an increase in the average chord length of the particles indicates an increase in the average particle size of the system), and the agglomeration phenomenon was still preserved after the addition of xanthate.

[0029] PVM measurement results are as follows Figure 3 As shown, the PVM measurement more intuitively verifies the results obtained by FBRM that oxidation leads to the agglomeration of pyrite and dolomite.

[0030] Table 1 shows the measured contact angles and surface potentials of pure pyrite and pure dolomite at different reaction stages after separation by the method of this embodiment, which prepares for subsequent extended DLVO simulation calculations.

[0031] Table 1. Mean contact angle (°) / surface potential (mV) of pure minerals in control group 1 and experimental group 1 in deionized water and glycerol.

[0032] The time-of-flight-secondary ion mass spectrometry results of the separated pure minerals are as follows: Figure 4 As shown in the figure. The results show that during the flotation of pyrite and dolomite, after the oxidation reaction, a large amount of iron carbonates and iron oxides were generated on the surface of the dolomite. It should be noted that since the specific quantity of fragments of a particular species does not play a decisive role in this embodiment, and the data volume is extremely large, information on the quantity of all species is not displayed in this embodiment.

[0033] Infrared spectroscopy test results as follows Figure 5 As shown: After oxidation, obvious adsorption characteristic peaks of iron xanthate were generated on the surface of dolomite. Combined with the analysis results of secondary ion mass spectrometry, it is proved that after the oxidation reaction occurred during the flotation of pyrite and dolomite, a large amount of iron carbonate was generated on the surface of dolomite, which provided an adsorption site for the collector xanthate, resulting in the dolomite being accidentally activated and floated.

[0034] Raman spectroscopy test results as follows Figure 6 As shown, after oxidation, a homogenization effect occurred on the surfaces of pyrite and dolomite (inorganic components tended to be similar), which further clarified the source of iron carbonate on the surface of dolomite and preliminarily explained the reason for the low separation efficiency of the mixed mineral system of pyrite and dolomite after oxidation reaction during flotation (homogenization effect, poor selectivity).

[0035] The test results of Fe 2p in X-ray photoelectron spectroscopy are as follows: Figure 7 As shown: During the flotation of pyrite and dolomite, after the oxidation reaction, the iron-containing substances generated on the surface of dolomite are mainly FeOOH, Fe(OH)2 and FeCO3 (combined with secondary ion testing, it was found that there are a large amount of iron carbonates and iron oxides. At the same time, the subsequent XPS O 1s spectrum also confirmed the presence of Fe(OH)2). The presence of Fe(OH)2 and FeCO3 provides the adsorption sites for xanthate and promotes the flotation of dolomite.

[0036] The test results of O 1s in X-ray photoelectron spectroscopy are as follows: Figure 8 As shown, the prediction of Fe 2p is verified: during the flotation of pyrite and dolomite, after the oxidation reaction, the iron-containing substances generated on the surface of dolomite are mainly FeOOH, Fe(OH)2 and FeCO3.

[0037] The test results of Mg 1s in X-ray photoelectron spectroscopy are as follows: Figure 9As shown: During the flotation of pyrite and dolomite, after the oxidation reaction, obvious MgCO3 was generated on the surface of pyrite, which explains the reason for the decrease in pyrite recovery after oxidation (MgCO3 hinders the adsorption of collectors on the surface of oxidized pyrite).

[0038] The test results of Ca 2p in X-ray photoelectron spectroscopy are as follows: Figure 10 As shown: During the flotation of pyrite and dolomite, after the oxidation reaction occurs, in addition to MgCO3, CaCO3 is also generated on the surface of pyrite, which is also the main factor that hinders the adsorption of collectors on the surface of oxidized pyrite. The theoretical calculation results of E-DLVO are as follows: Figure 11 and 12 As shown: During the flotation of pyrite and dolomite, after the oxidation reaction occurs, the van der Waals forces between particles change from positive to negative, resulting in the total interaction energy between particles changing from positive to negative, and heterogeneous agglomeration of particles occurs.

[0039] In summary, the interaction mechanism between pyrite and dolomite during the flotation process was obtained through the above research methods as follows: Figure 13 As shown: In the flotation process of pyrite and dolomite, heterogeneous agglomeration occurs between pyrite and dolomite after oxidation. Oxidation promotes the transfer of surface species between pyrite and dolomite, accelerating the homogenization process between minerals. Fe(OH)₂ and FeCO₃ formed on the surface of dolomite can act as a bridge for the reaction between dolomite and the collector xanthate, increasing the floatation ratio of dolomite. Conversely, FeOOH, calcium / magnesium hydroxides, and carbonates formed on the surface of pyrite hinder the adsorption of the collector, thus reducing the flotation recovery rate of pyrite. Theoretical calculations show that the oxidation reaction changes the van der Waals forces between particles from positive to negative, affecting the total interaction energy between pyrite and dolomite particles, leading to the industrial problem of poor separation efficiency between pyrite and dolomite containing pyrite.

[0040] Based on the above mechanistic research results, in the flotation process of refractory Carlin-type gold ore in this embodiment, the effects of regulating the oxidation reaction by reducing the aeration rate (reducing the oxidation rate) and adding EDTA-2Na (complexing oxidation product layer) and other reagents are shown in Table 2 below: Table 2. Regulation effect on a difficult-to-process low-grade Carlin-type gold deposit based on the conclusions of mechanism research.

[0041] The data in Table 2 show that, through theoretical research, the targeted reduction of aeration volume and the addition of EDTA-2Na to reduce the impact of oxidation on flotation successfully increased the enrichment ratio (concentrate grade / raw ore grade) of flotation concentrate from about 2.7 to about 3.5. At the same time, the recovery rate of Au increased from <80% to about 83%.

[0042] The above results indicate that the research method for studying the interaction mechanism between mineral particles in the flotation process proposed in this embodiment can provide theoretical guidance for the efficient separation of minerals by elucidating the mechanism by which the interaction between different types of mineral particles in different reaction stages affects the flotation effect, thereby achieving the goal of accurately and efficiently improving the flotation separation index of difficult-to-process complex ores.

[0043] For those skilled in the art, various corresponding changes and modifications can be made based on the above technical solutions and concepts, and all such changes and modifications should be included within the protection scope of the claims of this invention.

Claims

1. A method for studying the interaction mechanism between different mineral particles during flotation, characterized in that, Includes the following steps: S1. Pure mineral 1 and pure mineral 2 to be studied are prepared in advance. Pure mineral 1 and pure mineral 2 have different particle sizes. The prepared pure mineral 1 and pure mineral 2 are stored in two sample bags for later use. After the sample bags are evacuated, they are placed in a desiccator filled with nitrogen. S2. Mix pure mineral 1 and pure mineral 2 evenly to prepare a sample for later use; S3. After mixing the spare sample obtained in step S2 with water, put it into a stirrer equipped with a focused beam reflectance measuring instrument and a particle video microscope. During the stirring process, the average chord length of the mixed mineral particles at different reaction times is measured using the focused beam reflectance measuring instrument. After the average chord length of the particles stabilizes, the morphology of the current mixed mineral particles is obtained using the particle video microscope. A set amount of the current mixed mineral particles is taken as the sample of control group 1 while stirring. S4. Add the modifier to the remaining mixed mineral particle system in step S3, and after the set time, obtain the average chord length and morphology of the current mixed mineral particles. Take a set amount of the current mixed mineral particles as the sample of experimental group 1 while stirring. S5. Add the collector to the remaining mixed mineral particle system in step S4. After the set time, obtain the average chord length and morphology of the current mixed mineral particles. Take a set amount of the current mixed mineral particles as the sample of experimental group 2 while stirring. S6. The mixed mineral samples of control group 1 and experimental groups 1 and 2 were sieved separately. Due to the difference in particle size between pure mineral 1 and pure mineral 2, the two mineral samples that were uniformly mixed after the reaction in control group 1 and experimental groups 1 and 2 were re-separated into 6 groups of pure mineral samples representing different reaction stages, including: pure mineral 1 and pure mineral 2 in control group 1; pure mineral 1 and pure mineral 2 in experimental group 1; and pure mineral 1 and pure mineral 2 in experimental group 2. The 6 groups of pure mineral samples obtained by sieving were stored in different sample bags after vacuuming, and each sample bag was placed in a desiccator filled with nitrogen for later use. S7. Measure the Zeta potential and powder contact angle of the six groups of pure mineral samples obtained in step S6 using a surface potential meter and a contact angle meter, respectively; determine the species fragments and proportions of the surface products of the six groups of pure mineral samples obtained in step S6 using time-of-flight secondary ion mass spectrometry; measure the organic and inorganic spectra of the surface products of the six groups of pure mineral samples obtained in step S6 using infrared spectroscopy and Raman spectroscopy, respectively, and combine the species fragment and proportion measurement results to preliminarily determine the types and quantities of surface products of the six groups of pure mineral samples obtained in step S6; measure the elemental valence states and proportions of the surface products of the six groups of pure mineral samples obtained in step S6 using X-ray photoelectron spectroscopy to further clarify the types and quantities of surface products of the six groups of pure mineral samples. S8. Using the extended DLVO theory combined with Zeta potential and powder contact angle measurement results, the interaction forces between pure mineral 1 and pure mineral 2 in control group 1, between pure mineral 1 and pure mineral 2 in experimental group 1, and between pure mineral 1 and pure mineral 2 in experimental group 2 were calculated. The changes in the interaction forces between pure mineral 1 and pure mineral 2 at different reaction stages were obtained. Combined with the in-situ measurement results of focused beam reflectance measurement instrument and particle video microscope at different reaction stages, the correlation mechanism between the addition of modifiers and collectors in the flotation process and the surface products of ore, the interaction forces between mineral particles, and the agglomeration or dispersion behavior of mineral particles was obtained. This provides theoretical guidance for controlling the agglomeration and dispersion behavior of mineral particles by adding modifiers and collectors in the flotation process to achieve efficient separation between useful minerals and gangue mineral particles.

2. The research method according to claim 1, characterized in that, In step S1, the particle sizes of pure mineral 1 and pure mineral 2 are 58-75 μm and 25-38 μm, respectively; in step S6, the mixed mineral samples of control group 1 and experimental group 1 and experimental group 2 are sieved using a 325-mesh sieve.

3. The research method according to claim 1, characterized in that, In step S2, the total amount of pure mineral 1 and pure mineral 2 is 90-100 g, and the mass ratio of pure mineral 1 to pure mineral 2 is 1:1-1:5; in step S3, the mass ratio of the spare sample to water is 1:1-1:

2.

4. The research method according to claim 1, characterized in that, In step S3, the stirrer speed is maintained at 300-350 r / min.

5. The research method according to claim 1, characterized in that, In steps S4 and S5, the reaction time of the reagents is set to be 2-3 minutes, which is consistent with the industrial flotation production process.

6. The research method according to claim 1, characterized in that, In step S8, the total energy of the interactions between mineral particles Mainly includes van der Waals energy Electrostatic interaction energy between particles Hydrophobic interaction energy The expression is as follows: ； The formula for calculating the van der Waals energy is as follows: ； in, The calculation formula is: ； and These are the Hamaker constants for mineral 1 and mineral 2 in their respective media. It is the Hamaker constant of water under vacuum conditions, with a value of 4 × 10⁻⁶. -20 J; The Hamaker constant is calculated using the following equation: ； Electrostatic interaction energy between fine particles The calculation formula is as follows: ； ； ； in, It is the absolute permittivity in vacuum; is the dielectric constant of the water medium; and , respectively, are the surface potentials of mineral 1 and mineral 2, expressed as measured Zeta potential values ​​in V; H is the interaction distance between the two fine particles in nm; The length of Debye; Hydrophobic interactions between fine particles The calculation formula is as follows: ； Attenuation length The value of is 1 nm; H is the interaction distance between the two fine particles; This represents the minimum contact distance between mineral surfaces under equilibrium conditions. The energy constant for the interaction between polar interfaces is determined by the following equation: ； in, and These are the surface tension parameters for mineral 1, mineral 2, and the medium, respectively. For the water medium, = =25.5×10 -3 J / m 2 ; and Calculate using the following formula: ； in, Represents the surface energy of a liquid. Indicates the nonpolar / dispersive component of the liquid; Represents the nonpolar / dispersive component of a solid; Represents the Lewis acid parameter of a solid; This indicates the Lewis acid parameter of the liquid; The contact angle between liquid and solid surfaces, and the mineral's and The contact angle was obtained by measuring the contact angle in two solutions with known surface tensions.

7. The research method according to claim 6, characterized in that, The value is 8.854 × 10 -12 C -2 J -1 m -1 ; The value is 78.5 C. -2 J -1 m -1 ; The value for mixed mineral particles is 0.104 × 10⁻⁶. -9 m -1 ; The value is 0.15 nm; when water is the medium: 72.8×10 -3 J / m 2 , 21.8×10 -3 J / m 2 When glycerol is used as the medium, 6×10 -3 J / m 2 , 34×10 -3 J / m 2 , 3.92×10 -3 J / m 2 and It is 57.4×10 -3 J / m 2 .

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