An environmentally friendly gold beneficiation aid and its preparation method

Abstract

This invention provides an environmentally friendly gold beneficiation additive and its preparation method. The additive comprises 30-60 parts of a modified thiosulfate complexing component, 15-30 parts of a catalytically stabilizing oxidation component, 8-20 parts of an interfacial functional component, 10-25 parts of a buffer component, and 5-15 parts of a permeation aid. The preparation method involves: high-shear mixing of raw materials to obtain a homogeneous mixture; stabilizing the homogeneous mixture to obtain a matured material; and air-jetting the matured material to a D90 of 20-40 micrometers to obtain the additive product. This invention's additive, through an innovative combination of modified thiosulfate complexing components and a catalytic oxidation system, achieves highly efficient gold leaching while completely eliminating cyanide pollution, combining environmental breakthroughs with superior leaching efficiency.

Description

Technical Field

[0001] This invention belongs to the field of gold beneficiation technology, specifically relating to an environmentally friendly gold beneficiation additive and its preparation method. Background Technology

[0002] The gold extraction industry has long relied heavily on sodium cyanide, a highly toxic chemical, as a leaching agent. While its leaching efficiency is high and the technology is mature, the environmental and safety hazards it poses are also extremely serious. During cyanide-based gold extraction operations, cyanide residues in tailings dams and lean liquor can enter surrounding water bodies and soil through seepage and rainwater runoff, causing acute poisoning to aquatic organisms and potentially threatening human health through bioaccumulation. Furthermore, the transportation, storage, and use of cyanide require extremely high safety standards, significantly increasing the complexity of production management and operating costs.

[0003] To address the environmental risks posed by cyanide, researchers both within and outside the industry have devoted significant effort to developing non-toxic or low-toxicity alternative gold leaching technologies. Among these, the thiourea method is considered a promising option, as it forms cationic complexes in acidic media to dissolve gold. However, it is inherently unstable under acidic conditions, prone to decomposition leading to a surge in consumption, and is highly corrosive to equipment materials, limiting its large-scale industrial application. Another option is the lime-sulfur mixture method. While this method uses lime and sulfur as raw materials, resulting in relatively low cost and lower toxicity, its leaching reaction kinetics are slow, the leaching cycle is long, and the reagent solution has poor stability in air, causing the active ingredients to easily degrade, leading to large fluctuations in the leaching rate and unsatisfactory reproducibility.

[0004] In recent years, some leaching systems based on halides or thiosulfates have been studied, but these systems generally have their own limitations. For example, halide systems are highly corrosive to equipment and have poor selectivity for associated metals in the ore, leading to severe co-dissolution of impurities and complex subsequent purification processes. Thiosulfate systems require an ammonia-rich environment for stability; the volatility of ammonia not only creates a harsh working environment but also results in low actual reagent utilization. Furthermore, this system is sensitive to interfering elements such as copper and zinc in the ore, and the leaching effect is significantly reduced when processing complex symbiotic ores. For the increasing number of low-grade, oxidized, or carbonaceous interfering gold ores, existing environmentally friendly mineral processing aids generally exhibit insufficient adaptability.

[0005] Specifically, in heap leaching applications, poor matching between the permeability of the reagents and the pore structure of the ore can lead to uneven distribution of the leachate, creating leaching dead zones. In stirred leaching, side reactions between the reagents and gangue minerals can consume a large amount of active ingredients and may hinder the effective dissolution of gold due to the coating of reaction products on the surface of gold particles. Furthermore, many existing environmentally friendly additives have relatively simple formulations with a lack of synergistic effects between components. During long-term storage, their activity can decrease due to moisture absorption, oxidation, or photolysis, affecting the final performance.

[0006] Therefore, it is necessary to design an environmentally friendly gold beneficiation aid and its preparation method. Summary of the Invention

[0007] To overcome the shortcomings of existing technologies, an environmentally friendly gold beneficiation aid and its preparation method are provided.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] An environmentally friendly gold beneficiation additive, by weight, comprises 30-60 parts of modified thiosulfate complexing component, 15-30 parts of catalytic stabilizing oxidation component, 8-20 parts of interfacial functional component, 10-25 parts of buffer component and 5-15 parts of permeation aid.

[0010] The modified thiosulfate complex component is prepared by the following steps: ammonium thiosulfate and sodium thiosulfate are mixed at a mass ratio of 1:0.8-1.5, and 5%-15% of triammonium citrate and 3%-8% of disodium ethylenediaminetetraacetate are added. The mixture is ball-milled at 400-500 rpm for 2-2.5 hours, with a ball-to-material mass ratio of 10-12:1. Subsequently, the mixture is treated in a microwave reactor at 600-800W power and 90-110℃ for 30-50 minutes to obtain the modified thiosulfate complex component.

[0011] The modified thiosulfate complex component is prepared by the following steps: the ball milling process is carried out under nitrogen protection, and the specific surface area of ​​the material after ball milling is 0.8-1.5 m² / g.

[0012] The catalytically stabilized oxidizing component is prepared by the following steps: ammonium persulfate and potassium ferrate are mixed at a mass ratio of 2-2.2:1, dissolved, and then impregnated in an equal volume onto a mesoporous silica support. After impregnation for 2.5-3.5 hours, the mixture is dried at 130-150℃ for 2.5-3.5 hours, and finally calcined at 280-320℃ for 1.5-2.5 hours to obtain the catalytically stabilized oxidizing component.

[0013] The mesoporous silica carrier has a pore size of 5-15 nm, a specific surface area of ​​300-500 m² / g, and a loading of 25%-40%.

[0014] The interface functional component is prepared by the following steps: sodium dodecyl sulfonate and alkylphenol polyoxyethylene ether are premixed at a mass ratio of 1:1.5-2.0, and then treated in a low-temperature plasma device at a power of 150-250W and a pressure of 20-40 Pa under an argon-oxygen mixed gas for 8-15 minutes to obtain the interface functional component.

[0015] The oxygen volume fraction in the argon-oxygen mixture is 8%-12%.

[0016] The buffer component is a compound of ammonium bicarbonate and dipotassium hydrogen phosphate in a mass ratio of 1:0.8-1; the osmotic aid is a compound of ammonium thiocyanate and urea in a mass ratio of 1:1.8-2.2.

[0017] A method for preparing an environmentally friendly gold beneficiation additive includes the following steps: mixing 30-60 parts by weight of a modified thiosulfate complexing component, 15-30 parts by weight of a catalytically stabilizing oxidation component, 8-20 parts by weight of an interfacial functional component, 10-25 parts by weight of a buffer component, and 5-15 parts by weight of a penetration aid under high shear to obtain a homogeneous mixture; stabilizing the homogeneous mixture to obtain a stabilized material; and air-milling the stabilized material to a D90 of 20-40 micrometers to obtain the additive product.

[0018] The parameters for the high-shear mixing are: mixing at 40-50℃ and 1000-1200 rpm for 50-70 minutes;

[0019] The parameters for stabilization during the curing process are as follows: under nitrogen protection, the temperature is increased to 65-75°C at a rate of 15-25°C per hour, held at that temperature for 3-4 hours, and then cooled down using a programmed cooling method; the nitrogen purity during the curing process is not less than 99.99%, and the programmed cooling rate is controlled at 18-22°C per hour.

[0020] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows:

[0021] 1. The modified thiosulfate complex component of this invention is treated with a combined modification process of mechanochemical activation and microwave crystal transformation, which significantly improves the chemical stability of the component in the leaching system. This improvement makes it less likely for thiosulfate to undergo disproportionation reactions to generate harmful substances such as polythionates that cause passivation of the gold surface, thereby maintaining a continuous and efficient gold leaching capacity, while avoiding ineffective consumption caused by its own decomposition.

[0022] 2. The catalytically stabilized oxidizing component used in this invention creates a composite structure with highly selective oxidation capabilities by loading ammonium persulfate and potassium ferrate onto a mesoporous silica support. This structure can preferentially oxidize sulfide minerals or organic carbonaceous films coated on the surface of gold particles, exposing the gold reaction interface, while effectively controlling the oxidation potential to avoid excessive oxidative decomposition of the thiosulfate complexing agent. This synergistic effect is difficult to achieve in traditional physical mixing formulations.

[0023] 3. The interfacial functional components in this invention undergo low-temperature plasma surface treatment, which optimizes their molecular structure and surface energy. The treated surfactant can spread and adsorb more quickly on the surface of gold minerals and within the pores of the ore in the slurry, effectively reducing the liquid-solid interfacial tension. This not only improves the penetration and diffusion performance of the reagent, which helps to treat finely encapsulated gold particles, but also enhances the contact efficiency between the reagent and gold particles.

[0024] 4. The modified thiosulfate complexing component of the present invention provides stable and efficient gold complexing ability, the catalytic stabilizing oxidation component creates a suitable oxidation environment and removes diffusion barriers, and the interfacial functional component ensures efficient transport and contact of the reagent system in complex ore structures. The three promote each other and together constitute an efficient and stable gold leaching chemical system.

[0025] 5. This invention uses a compound of ammonium bicarbonate and dipotassium hydrogen phosphate as a buffer component, which can automatically maintain the pH of the system within a relatively narrow optimal range during the leaching process. This self-buffering property avoids the decomposition of thiosulfate or the decrease in gold leaching rate caused by pH fluctuations, reducing the difficulty of on-site operation. At the same time, the permeation aid of ammonium thiocyanate and urea further enhances the ability of the reagent to migrate into the pores and fractures inside the ore. Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] In the specific embodiments of this application, the sources of various main raw materials are briefly described as follows:

[0028] Ammonium thiosulfate, sodium thiosulfate, triammonium citrate, disodium ethylenediaminetetraacetate: Hubei Chengfeng Chemical Co., Ltd.

[0029] Ammonium persulfate, potassium ferrate: Sinopharm Chemical Reagent Co., Ltd.

[0030] Mesoporous silica carrier, sodium dodecyl sulfonate, alkylphenol polyoxyethylene ether: Shanghai Aladdin Biochemical Technology Co., Ltd.

[0031] Ammonium bicarbonate: Zhongchuang Xingyuan Chemical Technology Co., Ltd.

[0032] Dipotassium hydrogen phosphate: Jinan Century Tongda Chemical Co., Ltd.

[0033] Ammonium thiocyanate, urea: Hubei Chengfeng Chemical Co., Ltd.

[0034] The technical solution of this application is as follows:

[0035] An environmentally friendly gold beneficiation additive, by weight, comprises 30-60 parts of modified thiosulfate complexing component, 15-30 parts of catalytic stabilizing oxidation component, 8-20 parts of interfacial functional component, 10-25 parts of buffer component and 5-15 parts of permeation aid.

[0036] The modified thiosulfate complex component is prepared by the following steps: ammonium thiosulfate and sodium thiosulfate are mixed at a mass ratio of 1:0.8-1.5, and 5%-15% of triammonium citrate and 3%-8% of disodium ethylenediaminetetraacetate are added. The mixture is ball-milled at 400-500 rpm for 2-2.5 hours, with a ball-to-material mass ratio of 10-12:1. Subsequently, the mixture is treated in a microwave reactor at 600-800W power and 90-110℃ for 30-50 minutes to obtain the modified thiosulfate complex component.

[0037] The modified thiosulfate complex component is prepared by the following steps: the ball milling process is carried out under nitrogen protection, and the specific surface area of ​​the material after ball milling is 0.8-1.5 m² / g.

[0038] The catalytically stabilized oxidizing component is prepared by the following steps: ammonium persulfate and potassium ferrate are mixed at a mass ratio of 2-2.2:1, dissolved, and then impregnated in an equal volume onto a mesoporous silica support. After impregnation for 2.5-3.5 hours, the mixture is dried at 130-150℃ for 2.5-3.5 hours, and finally calcined at 280-320℃ for 1.5-2.5 hours to obtain the catalytically stabilized oxidizing component.

[0039] The mesoporous silica carrier has a pore size of 5-15 nm, a specific surface area of ​​300-500 m² / g, and a loading of 25%-40%.

[0040] The interface functional component is prepared by the following steps: sodium dodecyl sulfonate and alkylphenol polyoxyethylene ether are premixed at a mass ratio of 1:1.5-2.0, and then treated in a low-temperature plasma device at a power of 150-250W and a pressure of 20-40 Pa under an argon-oxygen mixed gas for 8-15 minutes to obtain the interface functional component.

[0041] The oxygen volume fraction in the argon-oxygen mixture is 8%-12%.

[0042] The buffer component is a compound of ammonium bicarbonate and dipotassium hydrogen phosphate in a mass ratio of 1:0.8-1; the osmotic aid is a compound of ammonium thiocyanate and urea in a mass ratio of 1:1.8-2.2.

[0043] A method for preparing an environmentally friendly gold beneficiation additive includes the following steps: mixing 30-60 parts by weight of a modified thiosulfate complexing component, 15-30 parts by weight of a catalytically stabilizing oxidation component, 8-20 parts by weight of an interfacial functional component, 10-25 parts by weight of a buffer component, and 5-15 parts by weight of a penetration aid under high shear to obtain a homogeneous mixture; stabilizing the homogeneous mixture to obtain a stabilized material; and air-milling the stabilized material to a D90 of 20-40 micrometers to obtain the additive product.

[0044] The parameters for the high-shear mixing are: mixing at 40-50℃ and 1000-1200 rpm for 50-70 minutes;

[0045] The parameters for stabilization during the curing process are as follows: under nitrogen protection, the temperature is increased to 65-75°C at a rate of 15-25°C per hour, held at that temperature for 3-4 hours, and then cooled down using a programmed cooling method; the nitrogen purity during the curing process is not less than 99.99%, and the programmed cooling rate is controlled at 18-22°C per hour.

[0046] The additive of this invention achieves efficient gold leaching while completely eliminating cyanide pollution through innovative compounding of modified thiosulfate complex components and catalytic oxidation system, combining environmental breakthroughs with advantages in leaching efficiency.

[0047] The present invention will be described in detail below through examples and comparative examples, but the scope of protection of the present invention is not limited to these examples. Unless otherwise specified, the chemical reagents and raw materials used in the following examples and comparative examples are all conventional commercially available products.

[0048] Example 1

[0049] This embodiment provides an environmentally friendly gold beneficiation additive, the preparation process of which is as follows. First, a modified thiosulfate complex component is prepared by mixing ammonium thiosulfate and sodium thiosulfate at a mass ratio of 1:0.8, wherein the total mass of thiosulfate is based on 100 parts. Then, 15% of triammonium citrate and 5.5% of disodium ethylenediaminetetraacetate (EDTA) are added to the mixture. The mixture is ball-milled at 400 rpm for 2.5 hours, with a ball-to-material mass ratio of 11:1. The ball milling process is carried out under nitrogen protection, and the specific surface area of ​​the material after ball milling is 0.8 square meters per gram. Subsequently, the ball-milled product is treated in a microwave reactor at 600 watts and 110 degrees Celsius for 40 minutes to obtain the modified thiosulfate complex component.

[0050] Secondly, a catalytically stable oxidation component was prepared by mixing ammonium persulfate and potassium ferrate at a mass ratio of 2:1, dissolving them, and then impregnating them in an equal volume onto a mesoporous silica support with a pore size of 5 nanometers and a specific surface area of ​​500 square meters per gram. After impregnation for 3.5 hours, the mixture was dried at 140 degrees Celsius for 2.5 hours and finally calcined at 320 degrees Celsius for 2.0 hours, with a loading of 32.5%, thus obtaining the catalytically stable oxidation component.

[0051] Then, the interfacial functional component was prepared by premixing sodium dodecyl sulfonate and alkylphenol polyoxyethylene ether at a mass ratio of 1:1.5, and treating them in a low-temperature plasma device at a power of 250 watts and a pressure of 30 Pa under an argon-oxygen mixed gas for 8 minutes. The oxygen volume fraction in the argon-oxygen mixed gas was 12%. The buffer component was prepared by compounding ammonium bicarbonate and dipotassium hydrogen phosphate at a mass ratio of 1:0.9, and the permeation aid was prepared by compounding ammonium thiocyanate and urea at a mass ratio of 1:1.8.

[0052] Finally, the auxiliary product was prepared by taking 60 parts of modified thiosulfate complexing component, 22.5 parts of catalytic stabilizing oxidation component, 8 parts of interfacial functional component, 25 parts of buffer component and 10 parts of permeation aid, and mixing them in a high-shear mixer at 50 degrees Celsius and 1100 rpm for 50 minutes to obtain a homogeneous mixture. The homogeneous mixture was heated to 70 degrees Celsius at 25 degrees Celsius per hour under nitrogen protection, held at that temperature for 3 hours and then cooled down at 22 degrees Celsius per hour. After maturation, the material was subjected to air jet milling to control the particle size D90 to 30 micrometers, thus obtaining an environmentally friendly gold beneficiation auxiliary product.

[0053] Example 2

[0054] In this embodiment, the similarities to those in Embodiment 1 will not be repeated, and the differences are as follows:

[0055] This embodiment provides an environmentally friendly gold beneficiation additive, the preparation process of which is as follows. First, a modified thiosulfate complex component is prepared by mixing ammonium thiosulfate and sodium thiosulfate at a mass ratio of 1:1.5, wherein the total mass of thiosulfate is based on 100 parts. Then, 5% triammonium citrate and 8% disodium ethylenediaminetetraacetate (EDTA) are added to the mixture. The mixture is ball-milled at 500 rpm for 2.0 hours, with a ball-to-material mass ratio of 10:1. The ball milling process is carried out under nitrogen protection, and the specific surface area of ​​the material after ball milling is 1.5 square meters per gram. Subsequently, the ball-milled product is treated in a microwave reactor at 800 watts and 90 degrees Celsius for 50 minutes to obtain the modified thiosulfate complex component.

[0056] Secondly, a catalytically stable oxidation component was prepared by mixing ammonium persulfate and potassium ferrate at a mass ratio of 2.2:1, dissolving them, and then impregnating them in an equal volume onto a mesoporous silica support with a pore size of 15 nanometers and a specific surface area of ​​300 square meters per gram. After impregnation for 2.5 hours, the mixture was dried at 150 degrees Celsius for 3.5 hours and finally calcined at 280 degrees Celsius for 2.5 hours, with a loading of 25%, to obtain the catalytically stable oxidation component.

[0057] Then, the interfacial functional component was prepared by premixing sodium dodecyl sulfonate and alkylphenol polyoxyethylene ether at a mass ratio of 1:2.0, and treating them in a low-temperature plasma device at 150 watts power and 40 Pa pressure under an argon-oxygen mixed gas for 15 minutes. The oxygen volume fraction in the argon-oxygen mixed gas was 8%. The buffer component was prepared by compounding ammonium bicarbonate and dipotassium hydrogen phosphate at a mass ratio of 1:1, and the permeation aid was prepared by compounding ammonium thiocyanate and urea at a mass ratio of 1:2.2.

[0058] Finally, the auxiliary product was prepared by taking 30 parts of modified thiosulfate complexing component, 30 parts of catalytic stabilizing oxidation component, 20 parts of interfacial functional component, 10 parts of buffer component and 15 parts of permeation aid, and mixing them in a high-shear mixer at 40 degrees Celsius and 1200 rpm for 70 minutes to obtain a homogeneous mixture. The homogeneous mixture was heated to 75 degrees Celsius at 15 degrees Celsius per hour under nitrogen protection, held at that temperature for 4 hours, and then cooled down at 18 degrees Celsius per hour. After maturation, the material was subjected to air jet milling, and the particle size D90 was controlled to be 20 micrometers to obtain an environmentally friendly gold beneficiation auxiliary product.

[0059] Example 3

[0060] In this embodiment, the similarities to those in Embodiment 1 will not be repeated, and the differences are as follows:

[0061] This embodiment provides an environmentally friendly gold beneficiation additive, the preparation process of which is as follows. First, a modified thiosulfate complex component is prepared by mixing ammonium thiosulfate and sodium thiosulfate at a mass ratio of 1:1.15, wherein the total mass of thiosulfate is based on 100 parts. Then, 10% of triammonium citrate and 3% of disodium ethylenediaminetetraacetate (EDTA) are added. The mixture is ball-milled in a ball mill at 450 rpm for 2.25 hours, with a ball-to-material mass ratio of 12:1. The ball milling process is carried out under nitrogen protection, and the specific surface area of ​​the material after ball milling is 1.15 square meters per gram. Subsequently, the ball-milled product is treated in a microwave reactor at 700 watts and 100 degrees Celsius for 30 minutes to obtain the modified thiosulfate complex component.

[0062] Secondly, a catalytically stable oxidation component was prepared by mixing ammonium persulfate and potassium ferrate at a mass ratio of 2.1:1, dissolving them, and then impregnating them in an equal volume onto a mesoporous silica support with a pore size of 10 nanometers and a specific surface area of ​​400 square meters per gram. After impregnation for 3.0 hours, the mixture was dried at 130 degrees Celsius for 3.0 hours and finally calcined at 300 degrees Celsius for 1.5 hours, with a loading of 40%, to obtain the catalytically stable oxidation component.

[0063] Then, the interfacial functional component was prepared by premixing sodium dodecyl sulfonate and alkylphenol polyoxyethylene ether at a mass ratio of 1:1.75. The mixture was then treated in a low-temperature plasma device at 200 watts and 20 Pa under an argon-oxygen mixed gas for 11.5 minutes. The oxygen volume fraction in the argon-oxygen mixed gas was 10%. The buffer component was prepared by compounding ammonium bicarbonate and dipotassium hydrogen phosphate at a mass ratio of 1:0.8, and the permeation aid was prepared by compounding ammonium thiocyanate and urea at a mass ratio of 1:2.0.

[0064] Finally, the auxiliary product was prepared by taking 45 parts of modified thiosulfate complexing component, 15 parts of catalytic stabilizing oxidation component, 14 parts of interfacial functional component, 17.5 parts of buffer component and 5 parts of permeation aid, and mixing them in a high-shear mixer at 45 degrees Celsius and 1000 rpm for 60 minutes to obtain a homogeneous mixture. The homogeneous mixture was heated to 65 degrees Celsius at 20 degrees Celsius per hour under nitrogen protection, held at that temperature for 3.5 hours, and then cooled down at 20 degrees Celsius per hour. After maturation, the material was subjected to air jet milling to control the particle size D90 to 40 micrometers, thus obtaining an environmentally friendly gold beneficiation auxiliary product.

[0065] Comparative Example 1

[0066] In this comparative example, the similarities with Example 2 will not be repeated, and the differences are as follows:

[0067] Instead of using modified thiosulfate complexing components, unmodified ammonium thiosulfate and sodium thiosulfate are simply mixed together.

[0068] Comparative Example 2

[0069] In this comparative example, the similarities with Example 2 will not be repeated, and the differences are as follows:

[0070] Instead of using catalytically stabilized oxidation components, the loading step is omitted, and ammonium persulfate and potassium ferrate are directly physically mixed.

[0071] Comparative Example 3

[0072] In this comparative example, the similarities with Example 2 will not be repeated, and the differences are as follows:

[0073] Instead of using interface functional components, a simple mixture of untreated sodium dodecyl sulfonate and alkylphenol polyoxyethylene ether is used.

[0074] Comparative Example 4

[0075] In this comparative example, the similarities with Example 2 will not be repeated, and the differences are as follows:

[0076] No buffer components are used, i.e., ammonium bicarbonate and dipotassium hydrogen phosphate are omitted.

[0077] Comparative Example 5

[0078] In this comparative example, the similarities with Example 2 will not be repeated, and the differences are as follows:

[0079] No osmotic aids are used, i.e., ammonium thiocyanate and urea are omitted.

[0080] Performance Test Results and Analysis

[0081] The additives were prepared according to the parameters of the examples and comparative examples, respectively. The testing methods employed were standard methods to ensure comparability of results. Gold leaching rate was tested using bottle leaching experiments. A fixed mass of gold ore sample was reacted with the additive solution under standard conditions, and the gold content in the leaching solution was determined to calculate the leaching rate. Thiosulfate consumption rate was determined by titration to measure the reduction of thiosulfate during leaching. Permeation rate was calculated by measuring the change in the drop height of the additive solution in a standard ore column over time. pH stability was assessed by monitoring the pH range during leaching. Post-storage activity retention was determined by placing the additive under accelerated storage conditions (40°C and 75% relative humidity) for 30 days, and then measuring its gold leaching rate as a percentage of the fresh sample. All tests were repeated three times, and the average value was taken. The specific test results are shown in Table 1.

[0082] As can be seen from Table 1, the present invention achieves excellent performance through component modification and synergistic effects. Regarding gold leaching rate, all examples achieved over 90%, while the comparative examples were significantly lower. This is attributed to the improved stability of the modified thiosulfate complex components. For example, in Comparative Example 1, the unmodified components led to an increased thiosulfate consumption rate, indicating that mechanochemical activation and microwave treatment effectively suppressed the disproportionation reaction and reduced the formation of harmful substances.

[0083] Table 1 Analysis of Test Results

[0084]

[0085] Regarding thiosulfate consumption rates, the examples all had rates below 10%, while the comparative examples all exceeded 15%, confirming that the loading structure of the catalytically stabilized oxidizing component optimized the oxidation potential and avoided excessive decomposition of the complexing agent. For example, in Comparative Example 2, the directly physically mixed oxidizing agent resulted in higher consumption. Permeation rate data showed that the examples were significantly higher than the comparative examples, especially Comparative Example 3, where the untreated interfacial functional component resulted in the lowest rate. This reflects the optimization of molecular structure and surface energy by plasma surface treatment, enhancing the spreading and adsorption of the reagent in the ore pores.

[0086] Regarding pH stability, the examples showed a narrower pH range, while Comparative Example 4, lacking a buffering component, exhibited a wider range, verifying the self-buffering capacity of the ammonium bicarbonate and dipotassium hydrogen phosphate complex and maintaining the optimal pH environment for the leaching system. The activity retention rates after storage were all above 95% in the examples, while below 90% in the comparative examples, indicating that the aging and stabilization process in the preparation method of this invention promotes the interaction between components and improves long-term storage stability.

[0087] The synergistic effect between the modified thiosulfate complexing component, the catalytic stabilizing oxidation component, and the interfacial functional component, as well as the auxiliary functions of the buffer component and the penetration aid, contribute to the efficient and stable gold immersion performance.

[0088] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An environmentally friendly gold ore dressing aid, characterized in that, By weight, the additive comprises 30-60 parts of modified thiosulfate complexing component, 15-30 parts of catalytic stabilizing oxidation component, 8-20 parts of interfacial functional component, 10-25 parts of buffer component and 5-15 parts of penetration aid. The modified thiosulfate complex component is prepared by the following steps: ammonium thiosulfate and sodium thiosulfate are mixed at a mass ratio of 1:0.8-1.5, and 5%-15% of triammonium citrate and 3%-8% of disodium ethylenediaminetetraacetate are added. The mixture is ball-milled at 400-500 rpm for 2-2.5 hours, with a ball-to-material mass ratio of 10-12:

1. Subsequently, the mixture is treated in a microwave reactor at 600-800W power and 90-110℃ for 30-50 minutes to obtain the modified thiosulfate complex component. The catalytically stabilized oxidizing component is prepared by the following steps: ammonium persulfate and potassium ferrate are mixed at a mass ratio of 2-2.2:1, dissolved, and then impregnated in an equal volume onto a mesoporous silica support. After impregnation for 2.5-3.5 hours, the mixture is dried at 130-150℃ for 2.5-3.5 hours, and finally calcined at 280-320℃ for 1.5-2.5 hours to obtain the catalytically stabilized oxidizing component. The interface functional component is prepared by the following steps: sodium dodecyl sulfonate and alkylphenol polyoxyethylene ether are premixed at a mass ratio of 1:1.5-2.0, and then treated in a low-temperature plasma device at a power of 150-250W and a pressure of 20-40 Pa under an argon-oxygen mixed gas for 8-15 minutes to obtain the interface functional component.

2. The environmentally friendly gold ore dressing aid according to claim 1, characterized in that, The modified thiosulfate complex component is prepared by the following steps: the ball milling process is carried out under nitrogen protection, and the specific surface area of ​​the material after ball milling is 0.8-1.5 m² / g.

3. The environmentally friendly gold ore dressing aid according to claim 2, characterized in that, The mesoporous silica carrier has a pore size of 5-15 nm, a specific surface area of ​​300-500 m² / g, and a loading of 25%-40%.

4. The environmentally friendly gold beneficiation additive according to claim 3, characterized in that, The oxygen volume fraction in the argon-oxygen mixture is 8%-12%.

5. The environmentally friendly gold beneficiation additive according to claim 1, characterized in that, The buffer component is a compound of ammonium bicarbonate and dipotassium hydrogen phosphate in a mass ratio of 1:0.8-1; the osmotic aid is a compound of ammonium thiocyanate and urea in a mass ratio of 1:1.8-2.

2.

6. A method for preparing the environmentally friendly gold beneficiation aid as described in any one of claims 1-5, characterized in that, The method includes the following steps: by mass, 30-60 parts of modified thiosulfate complexing component, 15-30 parts of catalytic stabilizing oxidation component, 8-20 parts of interfacial functional component, 10-25 parts of buffer component and 5-15 parts of penetration aid are mixed under high shear to obtain a homogeneous mixture; the homogeneous mixture is matured and stabilized to obtain matured material; the matured material is air-jet pulverized to D90 20-40 microns to obtain the auxiliary product.

7. The method for preparing an environmentally friendly gold beneficiation aid according to claim 6, characterized in that, The parameters for the high-shear mixing are: mixing at 40-50℃ and 1000-1200 rpm for 50-70 minutes; The parameters for stabilization during the curing process are as follows: under nitrogen protection, the temperature is increased to 65-75°C at a rate of 15-25°C per hour, held at that temperature for 3-4 hours, and then cooled down using a programmed cooling method; the nitrogen purity during the curing process is not less than 99.99%, and the programmed cooling rate is controlled at 18-22°C per hour.

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