Green gold and copper leaching agent and dump leaching process

Abstract

The invention provides a green gold and copper leaching agent and a dump leaching process, and belongs to the field of hydrometallurgy. The green gold and copper leaching agent comprises a green leaching agent main body, an auxiliary leaching agent and an impurity metal masking agent, the green leaching agent main body is a proline derivative, the impurity metal masking agent is one or two of glutathione and N-acetyl-L-cysteine, and the auxiliary leaching agent is one or more of hydrogen peroxide, calcium peroxide and sodium hypochlorite. Due to the application of the proline derivative, the non-toxicity and environmental protection property of a medicament system are ensured; the auxiliary leaching agent is beneficial to efficient chelation of metal ions and the medicament; the impurity metal masking agent ensures the green concept of a medicament system, and effective extraction of target metal is ensured through chelating of functional groups in a molecular structure of the impurity metal masking agent and impurity metal. According to the method, through mutual cooperation of the agent combination and the dump leaching process, green and efficient extraction of gold and copper metal resources is achieved, and meanwhile environmental friendliness and safety are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrometallurgy, and particularly relates to a green gold and copper leaching agent and a heap leaching process. Background Art

[0002] Porphyry copper deposits are the most typical copper deposits. According to the classification standard of copper ore reserves in China, they are respectively: Cu < 0.5 Mt (medium and small-sized), Cu ≥ 0.5 Mt (large-sized), and Cu ≥ 2.5 Mt (super-large-sized). According to the main metal economic endowment, porphyry copper deposits can be further subdivided into several sub-types such as porphyry Cu, Cu-Mo, Cu-Au, and Cu-Mo-Au; there are currently more than 70 porphyry copper deposits in China, mainly of the Cu-Mo, Cu-Au, and Cu-Mo-Au sub-types. In recent years, in the gold industry, the heap leaching method for gold extraction is one of the more direct and efficient methods for treating low-grade gold ores. The heap leaching process has the advantages of simple process, easy operation, few equipment, low power consumption, low investment, quick results, and low production cost. Heap leaching is used to treat low-grade ores with a grade of 0.5 - 3 g / t, and the recovery rates of copper and gold are about 40%, and can even reach 50%. It is widely welcomed by concentrators due to its high comprehensive resource utilization rate.

[0003] Currently, the heap leaching process uses cyanide to leach natural mineral gold and copper resources. Due to the highly toxic chemical properties of cyanide, there are potential safety hazards during its use, resulting in limited scope of application. In addition, in the cyanide heap leaching technology, impurity ions in the minerals will react with sodium cyanide, which not only leads to a huge consumption of reagents, but also makes the subsequent environmental protection treatment costs extremely high. Currently, the publicly available environmentally friendly reagent systems cannot achieve the ideal state of being cyanide-free.

[0004] In view of this, it is necessary to design an improved green gold and copper leaching agent and a heap leaching process to solve the above problems. Summary of the Invention

[0005] In view of the technical problems existing in the background art, the present application provides a green gold and copper leaching agent and a heap leaching process. In order to achieve green gold and copper extraction in the heap leaching process, by designing the main body of the green leaching agent, compounding and screening the leaching aid system, and optimizing the process parameters of the leaching aid system, it is ensured that gold and copper react with the green reagent, and the heap leaching process for extracting valuable metal resources of gold and copper with the green leaching agent is developed.

[0006] In a first aspect, the present application provides a green gold and copper leaching agent, which includes a main body of the green leaching agent, a leaching aid, and an impurity metal masking agent. The main body of the green leaching agent is a proline derivative, the impurity metal masking agent is one or both of glutathione and N-acetyl-L-cysteine, and the leaching aid is one or more of hydrogen peroxide, calcium peroxide, and sodium hypochlorite.

[0007] As a further improvement of the present application, the structural formula of the proline derivative is

[0008]

[0009] As a further improvement of the present application, the mass concentration of the main body of the green leaching agent is 20-50 g / L.

[0010] As a further improvement of the present application, the mass concentration of the co-leaching agent is 0.5-5 g / L.

[0011] As a further improvement of the present application, the mass concentration of the impurity metal masking agent is 5-20 g / L.

[0012] In a second aspect, the present application provides a heap leaching process, which uses the green gold and copper leaching agents described in the first aspect to leach gold and copper, and includes the following steps:

[0013] S1. Crush the gold- and copper-containing ore materials until the ore particles with a particle size of -0.074 mm account for 75-85% of the total mass of the materials, and then add them into a heap leaching container to obtain heap leaching ore materials;

[0014] S2. Adjust the pH value of the green gold and copper leaching agents to a predetermined range, and then add them into the heap leaching container to circulate and leach the heap leaching ore materials for a predetermined time to obtain gold- and copper-containing precious liquid and tailings;

[0015] S3. Use the fire assay method to detect the gold and copper contents in the tailings and calculate the leaching rate.

[0016] As a further improvement of the present application, the pH value of the green gold and copper leaching agents is ≥10.

[0017] As a further improvement of the present application, the intensity of the circulating leaching is 8-12 L / m 2 ·h.

[0018] As a further improvement of the present application, the circulating leaching time is 360-1080 h.

[0019] As a further improvement of the present application, the gold- and copper-containing ore materials include one or more of bio-oxidized slag, oxidized heap leaching slag, calcine, and flotation gold concentrate.

[0020] The beneficial effects of the present application are:

[0021] The present application provides a green gold and copper leaching agent and a heap leaching process. The green gold and copper leaching agent includes a main green leaching agent, a leaching aid, and an impurity metal masking agent. Among them, the main green leaching agent is a proline derivative, the impurity metal masking agent is one or both of glutathione and N-acetyl-L-cysteine, and the leaching aid is one or more of hydrogen peroxide, calcium peroxide, and sodium hypochlorite. Through careful design, the present application ensures the non-toxicity and environmental friendliness of the entire agent system, and at the same time realizes the efficient extraction of target metals.

[0022] In the present application, the main green leaching agent is a proline derivative, and the raw material of the proline derivative is derived from proline, which can avoid the safety hazards and environmental protection costs in the use of traditional cyanides. By screening the types of leaching aids, the efficient conversion of the valence states of target metals is achieved, ensuring the efficient chelation of subsequent metal ions with the green gold and copper leaching agent. The present application optimizes the types of impurity metal masking agents, among which the impurity metal masking agents include glutathione and N-acetyl-L-cysteine. Glutathione and N-acetyl-L-cysteine, as a dietary supplement, ensure the green concept of the agent system. The molecular structure of the impurity metal masking agent contains carboxyl, mercapto, and amino groups, which can chelate with impurity metals in a complex metal system, prevent unnecessary consumption of the agent, and ensure the effective extraction of target metals.

[0023] Through the mutual cooperation among the main leaching agent, the leaching aid, and the impurity metal masking agent in the present application, a synergistic effect is generated, realizing the green extraction of gold and copper mineral resources in the heap leaching process. Through this design, not only the efficiency of metal extraction is improved, but also the environmental friendliness and safety of the entire process are ensured.

[0024] The above description is only an overview of the technical solution of the present application. In order to be able to understand the technical means of the present application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features, and advantages of the present application more obvious and understandable, the following specifically illustrates the specific implementation manners of the present application. Brief Description of the Drawings

[0025] In order to more clearly illustrate the technical solution of the present application, the drawings used in the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0026] Figure 1 Schematic diagram of the potential chelation mechanism between the proline derivative and gold ions in the embodiment of the present application;

[0027] Figure 2 Schematic diagram of the hydrolysis mechanism of the impurity ion masking agent in the embodiment of the present application;

[0028] Figure 3 This is the synthetic route diagram of the proline derivative in the embodiments of the present application. Detailed implementation manners

[0029] Hereinafter, embodiments of the technical solutions of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to illustrate the technical solutions of the present application more clearly, and thus are only examples and cannot be used to limit the protection scope of the present application.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above accompanying drawings are intended to cover non-exclusive inclusion.

[0031] In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity, specific order or primary-secondary relationship of the indicated technical features. In the description of the embodiments of the present application, "a plurality" means more than two unless otherwise specifically defined.

[0032] Referring to "embodiments" herein means that specific features, structures or characteristics described in connection with the embodiments can be included in at least one embodiment of this application. The phrase appears in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0033] Currently, the heap leaching process uses cyanide to leach natural mineral gold and copper resources. Since cyanide is highly toxic, there are potential safety hazards during its use, resulting in limited scope of application. In the cyanide heap leaching technology, impurity ions react with sodium cyanide, leading to huge consumption of reagents and high subsequent environmental protection treatment costs. The currently disclosed environmentally friendly reagent systems cannot achieve the ideal state of cyanide-free.

[0034] To solve the technical problems of toxicity, safety hazards, high reagent consumption and environmental protection treatment costs faced by cyanide leaching of gold and copper resources in the current heap leaching process, the present application provides a green gold and copper leaching reagent and a heap leaching process. Among them, by using a new type of environmentally friendly reagent and optimizing the heap leaching process, the technical effects of significantly reducing toxicity, improving resource extraction efficiency, reducing reagent consumption and reducing environmental protection treatment costs can be achieved.

[0035] In a first aspect, an embodiment of the present application provides a green gold and copper leaching agent, which includes a green leaching agent main body, a leaching aid, and an impurity metal masking agent. The green leaching agent main body is a proline derivative, the impurity metal masking agent is one or two of glutathione and N-acetyl-L-cysteine, and the leaching aid is one or more of hydrogen peroxide, calcium peroxide, and sodium hypochlorite.

[0036] In the technical solution of the embodiment of the present application, a proline derivative is used as the green leaching agent main body, replacing traditional toxic agents such as cyanide, significantly reducing environmental pollution and health risks to operators. By adding a leaching aid, efficient conversion of the target metal valence is achieved, ensuring efficient chelation of subsequent metal ions with the green gold and copper leaching agent, effectively promoting the leaching rate and efficiency of metals such as gold and copper, and shortening the production cycle. The carboxyl, mercapto, and amino groups contained in the molecular structure of the impurity metal masking agent can chelate with impurity metals in a complex metal system environment, ensuring effective chelation of the leaching agent main body with the target metal, avoiding unnecessary consumption, improving the purity of the target metal, and reducing the complexity and cost in the subsequent refining process.

[0037] Further, in some embodiments, the structural formula of the proline derivative is

[0038]

[0039] In the technical solution of the embodiment of the present application, the proline derivative with a specific structure has high reactivity. Due to its containing multiple functional groups, it can effectively carry out complexation reactions with gold and copper ions, thereby realizing the leaching of metals.

[0040] Further, in some embodiments, the mass concentration of the green leaching agent main body is 20 - 50 g / L.

[0041] In the technical solution of the embodiment of the present application, within the appropriate concentration range, the active ingredients in the agent react more fully with the target metal ions, thereby improving the leaching efficiency.

[0042] Further, in some embodiments, the mass concentration of the leaching aid is 0.5 - 5 g / L.

[0043] In the technical solution of the embodiment of the present application, the leaching aid can effectively promote the dissolution of the target metal and enhance the leaching effect. The leaching aid and the green leaching agent main body act synergistically to improve the rate and selectivity of the leaching reaction.

[0044] Further, in some embodiments, the mass concentration of the impurity metal masking agent is 5 - 20 g / L.

[0045] In the technical solution of the embodiment of the present application, the impurity metal masking agent can effectively combine with impurity metal ions to form a stable complex. The masking of impurity metals is beneficial to optimizing the leaching process, making the leaching of target metals more efficient and selective. Through the mutual cooperation among the main body of the green leaching agent, the leaching aid, and the impurity metal masking agent, an efficient leaching system is formed, significantly improving the leaching rate and efficiency of target metals.

[0046] In a second aspect, the present application provides a heap leaching process, which uses the green gold and copper leaching agents described in the first aspect to leach gold and copper, and includes the following steps:

[0047] S1. Crush the gold- and copper-containing ore materials until the ore particles with a particle size of -0.074 mm account for 75-85% of the total mass of the materials, and then add them into a heap leaching container to obtain heap leaching ore materials;

[0048] S2. Adjust the pH value of the green gold and copper leaching agents to a predetermined range, and then add them into the heap leaching container to circulate and wash the heap leaching ore materials for a predetermined time to obtain gold- and copper-containing pregnant solution and tailings;

[0049] S3. Use the fire assay method to detect the gold and copper contents in the tailings and calculate the leaching rate.

[0050] The calculation formula is:

[0051] η=(m 1 β 1 -m 2 β 2 ) / m 1 β 1 ×100%;

[0052] In the formula, η is the leaching rate, and the unit is %;

[0053] m 1 is the mass of the original leaching sample, and the unit is g;

[0054] β 1 is the grade of the original leaching sample, and the unit is g / t;

[0055] m 2 is the mass of the tailings after leaching, and the unit is g;

[0056] β 2 is the grade of the tailings after leaching, and the unit is g / t.

[0057] Among them, by crushing the ore materials to a specific particle size and using green gold and copper leaching agents, the leaching efficiency of gold and copper is significantly improved. The cyclic leaching process ensures sufficient contact between the agents and the ore materials, further enhancing the leaching rate. The content of gold and copper in the tailings is tested by the fire assay method. Specifically, the test analysis method refers to "GB / T 7739". The gold and copper-containing precious liquid is detected by ICP-OES (Inductively Coupled Plasma Optical Emission Spectrometry). The calculated leaching rates of gold and copper are assisted and verified according to the concentrations of gold and copper in the gold and copper-containing precious liquid. The relative error between the two methods being less than 1% is considered valid data. By mutually verifying the two different detection methods, the data accuracy is improved.

[0058] Further, in some embodiments, the pH value of the green gold and copper leaching agents is ≥10.

[0059] In the technical solution of the embodiment of the present application, the alkaline environment can change the charge property of the surface of the ore materials, which helps the better contact between the gold and copper leaching agents and the ore materials, and improves the leaching rate and efficiency. At high pH values, the solubility of some impurity metals (such as iron, zinc, etc.) decreases, thereby reducing the leaching of impurities, which is beneficial to improving the purity and efficiency of subsequent precious liquid treatment.

[0060] Further, in some embodiments, the intensity of cyclic leaching is 8 - 12 L / m 2 ·h, and the time is 360 - 1080 h.

[0061] In the technical solution of the embodiment of the present application, the leaching intensity within an appropriate range ensures sufficient contact between the leaching liquid and the ore materials, while avoiding resource waste caused by overly strong leaching. The leaching time provides sufficient time for the target metals to be fully leached, while avoiding low efficiency caused by overly long leaching time.

[0062] Further, in some embodiments, the gold and copper-containing ore materials include one or more of bio-oxidized slag, oxidized heap leaching slag, calcine, and flotation gold concentrate.

[0063] In the technical solution of the embodiment of the present application, the green gold and copper leaching agents are applicable to various types of gold and copper-containing ore materials and can effectively extract gold and copper from these complex ores.

[0064] Some specific embodiments are listed below. It should be noted that the embodiments described below are exemplary and are only used to explain the present application and should not be construed as a limitation to the present application. For those without specific technologies or conditions noted in the embodiments, they shall be carried out according to the technologies or conditions described in the literature in the field or according to the product specifications. For reagents or instruments without the manufacturer noted, they are all conventional products that can be obtained through commercial purchase.

[0065] Example 1

[0066] This embodiment provides a heap leaching process, which uses green gold and copper leaching agents to leach gold and copper. Among them, the agent includes a green leaching agent main body, a leaching aid, and an impurity metal masking agent. The green leaching agent main body is a proline derivative, and its structural formula is The leaching aid is calcium peroxide, and the impurity metal masking agent is glutathione. The multi-element content of the ore containing gold and copper to be treated is shown in Table 1:

[0067] Table 1 Analysis results of multi-elements in raw ore

[0068] Element Au (g / t) Ag (g / t) Cu Pb Zn Content (%) 0.58 8.82 0.013 <0.0050 0.015 Element As Fe S C Sb Content (%) 0.0072 5.33 0.55 4.31 <0.0050 Element CaO MgO <![CDATA[Al 2 O 3 > <![CDATA[SiO 2 > / Content (%) 2.92 2.84 9.38 63.12 /

[0069] Specifically, it includes the following steps:

[0070] S1. Crush the ore material containing gold and copper until the ore particles with a particle size of -0.074 mm account for 80% of the total mass of the material. Then, add it into a heap leaching column with a height of 1.2 m and an inner diameter of 10 cm. The stacking height of the minerals is 1 m to obtain the heap leaching ore material;

[0071] S2. Add the green gold and copper leaching agent from the upper part of the heap leaching column. Among them, the concentration of the proline derivative is 40 g / L, the concentration of calcium peroxide is 2 g / L, the concentration of glutathione is 10 g / L, and the pH value of the agent is 12. After adding the agent into the heap leaching column, perform leaching from top to bottom at normal temperature and pressure. The dripping intensity is 10 L / m 2 ·h. Collect the leachate flowing out at the lower part and recycle it to the upper part of the heap leaching column by a pump. Perform cyclic leaching for 720 h to obtain the gold and copper rich solution and tailings;

[0072] S3. Use the fire assay method to detect the gold and copper content in the tailings and calculate the leaching rate.

[0073] Detect the gold and copper rich solution by ICP - OES, and assist in proving the leaching rate in step S3 according to the gold and copper concentrations in the gold and copper rich solution. The relative error between the two methods is less than 1%, proving that the data is valid.

[0074] Examples 2 - 4 and Comparative Examples 1 - 3

[0075] Examples 2 - 4 and Comparative Examples 1 - 3 respectively provide a heap leaching process. Compared with Example 1, the only difference is that the concentration of the proline derivative is different, and the rest is roughly the same as that of Example 1, so it will not be elaborated here.

[0076] Table 2 Leaching rates of gold and copper in Examples 1 - 4 and Comparative Examples 1 - 3

[0077]

[0078] As can be seen from Table 2, the green gold and copper leaching agents provided by the present application can be used to treat copper- and gold-containing ores by heap leaching process. The concentration of proline derivatives directly affects the leaching rates of gold and copper. At the same time, due to the difference in chemical activities of gold and copper, the reaction rate of proline derivatives with copper is faster. When the addition amount is 20 g / L, the limit leaching of copper can be achieved, and the leaching rate of copper is 93%. The main reason is that the impurity metal masking agent (glutathione) has a certain ability to chelate copper ions, but it is difficult to chelate gold ions. When the agent concentration is 50 g / L, the limit leaching of gold can be achieved, and the leaching rate of gold is 82%. The potential chelation mechanism of proline derivatives with gold ions is as Figure 1 shown.

[0079] Examples 5-9 and Comparative Examples 4-7

[0080] Examples 5-9 and Comparative Examples 4-7 respectively provide a heap leaching process. Compared with Example 1, the difference is only that the concentration of calcium peroxide is different, and the rest is roughly the same as that of Example 1, which will not be elaborated here.

[0081] Table 3 Leaching rates of gold and copper in Examples 5-9 and Comparative Examples 4-7

[0082]

[0083]

[0084] As can be seen from Table 3, the concentration of the leaching aid directly affects the leaching rates of gold and copper. When using only the main body of the green leaching agent and the impurity metal masking agent without the leaching aid, the leaching of gold in the ore cannot be achieved. At the same time, it can be found that due to the difference in chemical activities of gold and copper, the leaching effect of gold is directly related to the dosage of the leaching aid. When the dosage of the leaching aid is 5 g / L, the limit leaching of gold can be achieved, and the leaching rate of gold is 87%. As the dosage of the leaching aid further increases, the leaching rate of gold no longer increases.

[0085] Examples 10-13 and Comparative Examples 8-10

[0086] Examples 10-13 and Comparative Examples 8-10 respectively provide a heap leaching process. Compared with Example 1, the difference is only that the impurity metal masking agent is N-acetyl-L-cysteine and the concentration of proline derivatives is different, and the rest is roughly the same as that of Example 1, which will not be elaborated here.

[0087] Table 4 Leaching rates of gold and copper in Examples 10-13 and Comparative Examples 8-10

[0088]

[0089]

[0090] As can be seen from Table 4, the concentration of proline derivatives directly affects the leaching rates of gold and copper. Due to the difference in chemical activities between gold and copper, the reaction rate of proline derivatives with copper is faster. When the dosage of the agent is 20 g / L, the limit leaching of copper can be achieved, and the leaching rate of copper is 98%. When the concentration of the agent is 50 g / L, the limit leaching of gold can be achieved, and the leaching rate of gold is 83%. When using N-acetyl-L-cysteine, the leaching rate of copper under the optimal test parameters is slightly higher than that of glutathione. The main reason may be that the hydrolysis products of the two agents are different, resulting in differences in the leaching mechanism of copper ions, which are finally macroscopically reflected in the leaching rate index of copper. The hydrolysis mechanisms of glutathione and N-acetyl-L-cysteine are as Figure 2 shown.

[0091] Examples 14-16 and Comparative Examples 11-13

[0092] Examples 14-16 and Comparative Examples 11-13 respectively provide a heap leaching process. Compared with Example 4, the only difference is the concentration of glutathione, and the rest is roughly the same as Example 4, which will not be elaborated here.

[0093] Table 5 Leaching rates of gold and copper in Examples 14-16 and Comparative Examples 11-13

[0094] Item Glutathione Concentration (g / L) Leaching Rate of Gold (%) Leaching Rate of Copper (%) Example 4 10 82 93 Example 14 5 72 90 Example 15 15 83 97 Example 16 20 84 97 Comparative Example 11 1 43 72 Comparative Example 12 21 84 97 Comparative Example 13 30 84 97

[0095] As can be seen from Table 5, the concentration of the impurity ion masking agent (glutathione) directly affects the leaching rates of gold and copper, especially more significantly for the leaching rate of gold. When the concentration of glutathione is too low, the impurity ions react with the main body of the leaching agent, reducing the concentration of the main body of the leaching agent and destroying the optimal process parameters. As the dosage of glutathione further increases, the leaching rate of gold no longer increases.

[0096] Examples 17-19 and Comparative Examples 14-16

[0097] Examples 17-19 and Comparative Examples 14-16 respectively provide a heap leaching process. Compared with Example 13, the only difference is the concentration of N-acetyl-L-cysteine, and the rest is roughly the same as Example 13, which will not be elaborated here.

[0098] Table 6 Leaching rates of gold and copper in Examples 17-19 and Comparative Examples 14-16

[0099]

[0100] As shown in Table 6, the concentration of impurity ion masking agent (N-acetyl-L-cysteine) directly affects the leaching rate of gold and copper, especially the leaching rate of gold. When the concentration of N-acetyl-L-cysteine ​​is too low, the impurity ions react with the main body of the leaching agent, the concentration of the main body of the leaching agent decreases, the optimal process parameters are destroyed, and the leaching rate of gold is reduced.

[0101] Embodiment 20

[0102] This example provides a method for synthesizing a proline derivative used in the heap leaching process in Example 1, such as Figure 3 As shown, the following steps are included:

[0103] S1. Add 0.5 mol of proline to 1 L of ethylene glycol solution, stir for 30 min, then add 5 mL of sulfuric acid each time, add 50 ml of sulfuric acid in 10 times, wait for heat to return to room temperature, heat under reflux and stir for 36 h. After the reaction is complete, filter while hot and collect the solid precipitate.

[0104] S2. Add 50g of sodium hydroxide to 500mL of CS 2 The solution was stirred for 5 min, the solid precipitate obtained in step S1 was added, and the mixture was heated to 50°C and stirred and refluxed for 3 h. After the solution turned from yellow to orange, it was stirred and refluxed for another 2 h. The liquid phase was collected by filtration and vacuum evaporated to obtain the main proline derivative of the green leaching agent with a yield of 52%.

[0105] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A green gold and copper leaching agent, characterized in that: The invention comprises a green leaching agent body, a leaching aid and an impurity metal masking agent, wherein the green leaching agent body is a proline derivative, the impurity metal masking agent is one or two of glutathione and N-acetyl-L-cysteine, and the leaching aid is one or more of hydrogen peroxide, calcium peroxide and sodium hypochlorite.

2. The green gold and copper leaching agent according to claim 1, characterized in that: The structural formula of the proline derivative is 3. The green gold and copper leaching agent according to claim 1, characterized in that: The mass concentration of the green leaching agent body is 20-50 g / L.

4. The green gold and copper leaching agent according to claim 3, characterized in that: The mass concentration of the soaking aid is 0.5-5 g / L.

5. The green gold and copper leaching agent according to claim 4, characterized in that: The mass concentration of the impurity metal masking agent is 5 to 20 g / L.

6. A heap leaching process, characterized in that: The green gold and copper leaching agent according to any one of claims 1 to 5 is used to leach gold and copper, comprising the following steps: S1. Crushing the gold and copper ore material to a particle size of -0.074 mm, the ore powder accounts for 75 to 85% of the total mass of the material, and then adding it to the heap leaching container to obtain the heap leaching ore; S2. adjusting the pH value of the green gold and copper leaching agent to a predetermined range, and then adding the agent to the heap leaching container, cyclically leaching the heap leaching material for a predetermined time to obtain a gold-containing and copper-containing precious liquid and tailings; S3. Using fire assay method to detect the content of gold and copper in the tailings, and calculate the leaching rate.

7. The heap leaching process according to claim 6, characterized in that: The pH value of the green gold and copper leaching agent is ≥10.

8. The heap leaching process according to claim 6, characterized in that: The intensity of the circulating elution is 8 to 12 L / m 2 ·h.

9. The heap leaching process according to claim 8, characterized in that: The cycle elution time is 360 to 1080 hours.

10. The heap leaching process according to claim 6, characterized in that: The gold and copper mineral materials include one or more of biological oxidation slag, oxidation heap leaching slag, roasted sand, and flotation gold concentrate.

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