Gold extraction method for carbonaceous refractory gold ore

Abstract

The present application provides a gold extraction method for refractory carbonaceous gold ore, belonging to the technical field of hydrometallurgy. In the present invention, the refractory carbonaceous gold ore is placed in an electrolytic cell containing an electrolyte solution, the pH of the pulp is adjusted to 2 < pH ≤ 7, a voltage is applied to the electrodes, and electrochemical oxidation pretreatment is carried out. Subsequently, the pH value of the pulp is adjusted to 1 ≤ pH ≤ 2, and an anion resin is added, and the pulp is stirred for gold leaching to achieve efficient recovery of gold. Through the electrochemical oxidation pretreatment, the present invention can effectively achieve the oxidation and removal of carbon, eliminating the "gold-robbing performance" of carbon on gold. At the same time, the acidic leaching and recovery of gold in the gold ore after pretreatment are successfully realized, reducing the acid-base transformation steps of the oxidation slag, and realizing non-cyanide leaching of gold. It can not only efficiently recover gold in refractory carbonaceous gold ore, but also has a short process flow, simple operation and environmental friendliness, providing a highly valuable technical solution for the field of hydrometallurgy of precious metals.

Description

Technical Field

[0001] The invention relates to the technical field of hydrometallurgy, and in particular to a method for extracting gold from carbon-containing refractory gold ore. Background Art

[0002] Driven by the strong demand for sustained economic development, the demand for gold, as a key cornerstone of currency reserves and an indispensable metal for high-tech industries, has shown a rapid growth trend in recent years. Benefiting from this, the gold industry has made great progress, and my country has been ranked first in the world in gold production for many years with its excellent production capacity. However, the proportion of refractory gold resources in existing gold mines has increased year by year. Among the proven geological reserves, the gold reserves of refractory gold mines exceed 3,000 tons, accounting for more than 1 / 3 of the total proven reserves. Therefore, it is urgent to develop a convenient and efficient method for refractory gold mines.

[0003] Currently, cyanidation still occupies a dominant position in the gold industry, and more than 80% of the world's annual gold production relies on this process. However, cyanidation is not perfect. Although cyanidation gold leaching has a mature process, it is highly toxic, pollutes the environment, and has a slow leaching rate. Especially when treating carbon-containing gold ores, the "gold-robbing effect" produced by carbon will cause the cyanidation leaching index to deteriorate significantly.

[0004] The roasting method is to roast the ore within a specific temperature range to make the carbon oxidize or lose its activity, and the sulfide is also oxidized, thereby opening the fine packaging structure of the fine-grained gold ore and creating favorable conditions for subsequent cyanide leaching. Although the roasting method can improve the recovery rate of gold, its investment cost is high, energy consumption is huge, and it is more polluting to the environment. Against the backdrop of increasingly stringent environmental standards, these disadvantages are becoming more and more prominent.

[0005] In addition, relevant studies have shown that adding oxidants such as chlorine and hypochlorite to the slurry can remove carbon from difficult-to-treat gold ores and oxidize carbon-containing substances into CO or CO2, thereby reducing the "gold-robbing effect" of carbonaceous minerals. However, chlorine has problems such as low utilization rate and environmental pollution in practical applications, which greatly limits its industrial application. Although sodium hypochlorite can increase the leaching rate of gold in carbonaceous gold ores, sodium hypochlorite is a liquid, which makes it face great difficulties in transportation and storage.

[0006] In the prior art, a new method for warm leaching of carbonaceous gold ore is provided in the patent with the publication number CN107988489A. Ore grinding: The raw ore is crushed by a crushing device and then ground to obtain pulp; Leaching pretreatment: The mass concentration of the pulp obtained by grinding is adjusted to 40%, poured into a stirrer, and an oxidant, a leaching aid, and a pH adjuster are added in sequence, and stirred for 2 hours; Warm cyanidation carbon leaching: The pretreated pulp is poured into a heat preservation container and heated to 90 °C, and the pulp temperature is kept at 90 °C unchanged. Then, an adsorbent and a gold leaching agent are added in sequence, the heat preservation container is sealed, and it is kept still for 24 hours to extract the gold-loaded carbon, and the solid-liquid separation of the pulp is carried out. However, in the gold leaching process of this method, the raw materials are highly toxic, cause environmental pollution, and are greatly affected by the carbon in the ore during subsequent gold extraction. In the patent with the publication number CN105838901B, a method for roasting pretreatment of gold extraction from sulfur-arsenic and carbon-containing gold ore is provided. The sulfur-arsenic and carbon-containing gold ore is mixed after adding sodium salt and quickly roasted under oxygen-rich conditions. The obtained roasted ore is washed with water and then subjected to cyanidation leaching. Although this method has good removal effects of sulfur-arsenic and carbon and a high gold leaching rate, the energy consumption is huge and the environmental pollution is relatively serious. Summary of the Invention

[0007] In view of the technical problems existing in the background art, the present application provides a method for gold extraction from carbonaceous refractory gold ore, aiming to solve the problems of difficult elimination of carbon in existing carbonaceous refractory gold ore, complex process flow, large energy consumption in the gold leaching process, and environmental pollution.

[0008] The present application provides a method for gold extraction from carbonaceous refractory gold ore, comprising the following steps:

[0009] S1. The carbonaceous gold ore is finely ground, added into an electrolytic cell, and after stirring evenly, a first pH adjuster is added to adjust the pH value of the pulp so that 2 < pH ≤ 7, and electrolytic pretreatment is carried out;

[0010] S2. Anion exchange resin is continuously added to the pulp, and a second pH adjuster is added to adjust the pH value of the pulp so that 1 ≤ pH ≤ 2, and stirring gold leaching is carried out;

[0011] S3. The gold-loaded resin in the pulp is separated, the tail liquid is recycled after impurity removal and purification, and the tail slag is neutralized and discharged.

[0012] In the technical solution of the embodiment of the present application, the robbery effect of carbonaceous minerals is eliminated through electrochemical pretreatment, and direct leaching of gold can be achieved without solid-liquid separation, significantly improving the recovery rate of gold in carbonaceous gold ore. The acidic leaching and recovery of gold in the gold ore after pretreatment are successfully realized, the acid-base transformation step of the oxidation slag is reduced, and the synchronous development of the pretreatment and leaching recovery processes of carbonaceous gold ore is achieved. During the entire technological process, the liquid is recycled to maximize the utilization of resources; the tailings do not contain toxic and harmful substances, eliminating potential environmental pollution hazards; at the same time, no harmful waste gas is generated during the entire production process, fully demonstrating the green and environmental protection characteristics of this process, which conforms to the current concept of sustainable development. In addition, by stepwise adjusting the pH value of the pulp, while ensuring the removal of impurities such as carbon in the minerals, a high leaching rate of gold is guaranteed. In the subsequent gold extraction process, gold can be directly extracted by conventional resin, and the extraction effect is good. This method has the advantages of simple equipment, short process, low reagent consumption, good environmental benefits, and good metal recovery effect, showing good application prospects in the utilization of carbonaceous gold ore treatment.

[0013] In some embodiments, in step S1, the voltage of the electrolysis is 2 - 12V, and the time of the electrolysis is 3 - 8h.

[0014] In this embodiment, through specific electrolysis voltage and electrolysis time, sulfides, carbonaceous minerals, etc. in the gold ore can be oxidized by the oxides generated at the anode, exposing the gold wrapped by sulfides and eliminating the influence of carbonaceous minerals, etc.

[0015] In some embodiments, in step S2, the time of the stirring leaching is 1 - 6h.

[0016] In this embodiment, through stirring leaching, the gold dissolved in the liquid phase in the pulp comes into full contact with the resin, and the gold is adsorbed by the resin to achieve the recovery of gold.

[0017] In some embodiments, in step S1, the electrolyte in the electrolytic solution is one or any combination of two of sodium chloride and / or potassium chloride, sodium bromide and / or potassium bromide, potassium iodide and / or sodium iodide; the mass concentration of the electrolyte is 20 - 200g / L.

[0018] In this embodiment, using one or any combination of two of sodium chloride and / or potassium chloride, sodium bromide and / or potassium bromide, potassium iodide and / or sodium iodide as the electrolyte, oxides are generated by anode electrolysis to oxidize impurities such as sulfides and carbonaceous minerals in the gold ore.

[0019] In some embodiments, in step S1, the fine grinding means that the grinding fineness is 80% - 95% of -0.074mm.

[0020] In this embodiment, by grinding the minerals to a specific fineness, the subsequent electrolysis for impurity elimination and gold leaching effect are better.

[0021] In some embodiments, in step S1, the mass concentration of the pulp in the electrolytic cell is 5% - 40%.

[0022] In some embodiments, in step S1, the first pH regulator is hydrochloric acid.

[0023] In this embodiment, first, the pH value of the pulp is adjusted to 2 - 7 with hydrochloric acid. Combined with the electrolysis conditions, carbon and sulfides in the minerals can be electrolytically oxidized, without directly adjusting the pH value of the pulp to the range suitable for gold electrolysis, preventing sulfides on the surface of gold minerals from producing acid during electrolysis, resulting in too low pH value of the solution and seriously affecting the subsequent effect of resin adsorption of gold.

[0024] In some embodiments, in step S2, the second pH regulator is hydrochloric acid or sulfuric acid.

[0025] In this embodiment, during the gold leaching process, the pH value of the pulp is adjusted to the range suitable for gold electrolysis again. By adjusting the pH value of the pulp step by step, the effect of resin adsorption of gold is not affected.

[0026] In some embodiments, in step S2, the anion exchange resins include: resins of models YKTG01, YKTG04, D201, D201×7, and XJZY; the addition amount of the anion exchange resin is 10 - 40 ml / L.

[0027] In this embodiment, due to the step - by - step pH adjustment, the gold - adsorbing resin can be a conventional resin with good adsorption effect.

[0028] In some embodiments, in step S1, the material of the electrolytic cell is one of PP, fiberglass, PPH, or PPR; the material of the anode of the electrolytic cell is one of graphite, ruthenium - plated titanium plate, or ruthenium - plated titanium mesh, and the material of the cathode is one of titanium plate, titanium mesh, or graphite.

[0029] In this embodiment, a suitable electrolytic material can make the electrolysis reaction proceed smoothly.

[0030] The above description is only an overview of the technical solution of this application. In order to understand the technical means of this 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 this application more obvious and understandable, the following specific embodiments of this application are given. Specific Embodiments

[0031] The embodiments of the technical solution of this application are described in detail below. The following embodiments are only used to illustrate the technical solution of this application more clearly, so they are only examples and cannot be used to limit the protection scope of this application.

[0032] As used herein, the mention of "embodiment" means that the specific features, structures or characteristics described in connection with the embodiment may be included in at least one embodiment of the present application. The appearance of this phrase at various positions 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 will explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments.

[0033] In the description of the embodiments of the present application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the front and back associated objects.

[0034] In order to solve the problems of difficult carbon elimination in existing carbonaceous refractory gold ores, easy occurrence of gold-robbing effect, large energy consumption in the gold leaching process, and environmental pollution, etc., the present application provides a gold extraction method for carbonaceous refractory gold ores. By electrochemical pretreatment, the gold-robbing effect of carbonaceous minerals is eliminated, and direct leaching of gold can be achieved without solid-liquid separation, significantly improving the gold recovery rate in carbonaceous gold ores. The acidic leaching and recovery of gold in the gold ore after pretreatment are successfully realized, the acid-base transformation step of the oxidation slag is reduced, and the synchronous development of the pretreatment and leaching recovery processes of carbonaceous gold ores is achieved. During the entire process, the liquid is recycled to maximize resource utilization; the tailings do not contain toxic and harmful substances, eliminating potential environmental pollution hazards; at the same time, no harmful waste gas is generated during the entire production process, fully demonstrating the green and environmental protection characteristics of this process, which conforms to the current concept of sustainable development. In addition, since conventional resins have poor adsorption effects under conditions of too low pH value, and sulfides in gold ores will produce acid during electrolysis, the pH value will gradually decrease during electrolysis, resulting in the fact that the method of adjusting the pH value in one step in the prior art often affects the adsorption effect of conventional resins on gold due to the gradual decrease of the pH value. However, the present application adjusts the pH value of the pulp step by step to ensure the removal of impurities such as carbon in the minerals while ensuring a high leaching rate of gold. In the subsequent gold extraction process, gold can be directly extracted by conventional resins and has a good extraction effect. This method has the advantages of simple equipment, short process, low reagent consumption, good environmental benefits and good metal recovery effect, and shows good application prospects in the utilization of carbonaceous gold ores.

[0035] The present application provides a gold extraction method for carbonaceous refractory gold ores, comprising the following steps:

[0036] S1. Finely grind the carbonaceous gold ore, add it to an electrolytic cell, stir evenly, and then add a first pH regulator to adjust the pH value of the pulp so that 2 < pH ≤ 7, and perform electrolytic pretreatment;

[0037] S2. Continuously add anion exchange resin to the pulp, add a second pH regulator to adjust the pH value of the pulp to make 1 ≤ pH ≤ 2, and stir for gold leaching.

[0038] S3. Separate the gold-loaded resin in the pulp, recycle the tail liquid after impurity removal and purification, and discharge the tailings after neutralization.

[0039] Further, in some embodiments, in step S1, the voltage of the electrolysis is 2 - 12 V, and the time of the electrolysis is 3 - 8 h.

[0040] In the technical solution of the embodiment of the present application, through specific electrolysis voltage and electrolysis time, sulfides, carbonaceous minerals, etc. in the gold ore can be oxidized by the oxides generated at the anode, so that the sulfide-coated gold is exposed, and the influence of carbonaceous minerals, etc. is eliminated.

[0041] Further, in some embodiments, in step S2, the time of the stirring leaching is 1 - 6 h.

[0042] In the technical solution of the embodiment of the present application, through stirring leaching, the gold dissolved in the liquid phase in the pulp is fully contacted with the resin, so that the gold is adsorbed by the resin, and the recovery of gold is realized.

[0043] Further, in some embodiments, in step S1, the electrolyte in the electrolytic solution is one or any combination of two of sodium chloride and / or potassium chloride, sodium bromide and / or potassium bromide, potassium iodide and / or sodium iodide; the mass concentration of the electrolyte is 20 - 200 g / L.

[0044] In the technical solution of the embodiment of the present application, using one or any combination of two of sodium chloride and / or potassium chloride, sodium bromide and / or potassium bromide, potassium iodide and / or sodium iodide as the electrolyte, the anode electrolysis generates oxides to oxidize impurities such as sulfides and carbonaceous minerals in the gold ore.

[0045] Further, in some embodiments, in step S1, the fine grinding means that the grinding fineness is 80% - 95% of -0.074 mm.

[0046] In the technical solution of the embodiment of the present application, by grinding the minerals to a specific fineness, the subsequent electrolysis can better eliminate impurities and the gold leaching effect.

[0047] Further, in some embodiments, in step S1, the mass concentration of the pulp in the electrolytic cell is 5% - 40%.

[0048] Further, in some embodiments, in step S1, the first pH regulator is hydrochloric acid.

[0049] In the technical solution of the embodiment of the present application, first, the pH value of the pulp is adjusted to 2-7 with hydrochloric acid. Combined with the electrolysis conditions, carbon and sulfides in the minerals can be electrolytically oxidized, without directly adjusting the pH value of the pulp to the range suitable for electrolytic gold, preventing the sulfides on the surface of the gold minerals from generating acid during electrolysis, resulting in too low pH value of the solution and seriously affecting the effect of resin adsorption of gold subsequently.

[0050] Further, in some embodiments, in step S2, the second pH regulator is hydrochloric acid or sulfuric acid.

[0051] In the technical solution of the embodiment of the present application, during the gold leaching process, the pH value of the pulp is adjusted to the range suitable for electrolytic gold again. By adjusting the pH value of the pulp step by step, the effect of resin adsorption of gold is not affected.

[0052] Further, in some embodiments, in step S2, the anion exchange resins include: resins of models YKTG01, YKTG04, D201, D201×7, and XJZY; the addition amount of the anion exchange resin is 10-40 ml / L.

[0053] In the technical solution of the embodiment of the present application, due to the step-by-step adjustment of the pH value, the gold adsorption resin can be a conventional resin and has a good adsorption effect.

[0054] Further, in some embodiments, in step S1, the material of the electrolytic cell is one of PP, fiberglass, PPH, or PPR; the material of the anode of the electrolytic cell is one of graphite, ruthenium-plated titanium plate, or ruthenium-plated titanium mesh, and the material of the cathode is one of titanium plate, titanium mesh, or graphite.

[0055] In the technical solution of the embodiment of the present application, a suitable electrolytic material can make the electrolysis reaction proceed smoothly.

[0056] 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 not specified in the embodiments regarding specific technologies or conditions, they shall be carried out according to the technologies or conditions described in the literature in this field or according to the product specifications. For reagents or instruments not specified by the manufacturer, they are all conventional products that can be obtained through commercial purchase.

[0057] Example 1

[0058] This embodiment provides a gold extraction method for refractory carbon-containing gold ore, specifically including the following steps:

[0059] (1) Grind the gold ore to a mass content of -0.074 mm accounting for 80%, add it to a PP electrolytic cell containing 20 g / L sodium chloride electrolyte, with a ruthenium-plated titanium plate as the anode and a titanium mesh as the cathode. The mass concentration of the pulp in the electrolytic cell is 5%, and use hydrochloric acid to adjust the pH of the pulp to 7. Apply a voltage of 12 V between the anode and the cathode, and perform electrolytic pretreatment for 3 hours under stirring.

[0060] (2) Add 10 ml / L of D201×7 macroporous anion exchange resin to the pulp, and use hydrochloric acid to maintain the pH of the pulp solution at 2 during the leaching process, and perform stirring leaching for 6 hours.

[0061] (3) After the leaching is completed, separate the gold-loaded resin in the pulp, and then perform solid-liquid separation.

[0062] The source and performance parameters of the raw materials are as follows:

[0063] All the raw materials used are carbonaceous refractory gold ores produced by a domestic mining enterprise. The main element contents are shown in Table 1. Among them, carbon mainly exists in the forms of organic carbon and elemental carbon, with contents of 47.18% and 22.99% respectively, and the carbonate content is 29.83%. Under the condition of sufficient cyanide, the direct cyanidation leaching rate of this raw material is 23.52%.

[0064] Table 1 Main element contents of the original ore

[0065]

[0066] Analyze the gold grade in the leaching residue of this example, and calculate the gold leaching rate to be 93.30%.

[0067] Examples 2 - 3 and Comparative Examples 1 - 2

[0068] Examples 2 - 3 and Comparative Examples 1 - 2 respectively provide a gold extraction method for carbonaceous refractory gold ores. Compared with Example 1, the difference lies in the different voltages in step (1). The voltages corresponding to each example and comparative example are shown in Table 2. The other steps are roughly the same as those in Example 1 and will not be elaborated here.

[0069] Table 2 Voltages in Examples 2 - 3 and Comparative Examples 1 - 2

[0070]

[0071] Analyze the gold grade in the leaching residues of Examples 2 - 3 and Comparative Examples 1 - 2 respectively, and calculate the gold leaching rates as shown in Table 3 respectively.

[0072] Table 3 Gold leaching rates in Examples 2 - 3 and Comparative Examples 1 - 2

[0073]

[0074] From the gold leaching rates in Examples 1 to 3 and Comparative Examples 1 to 2, it can be seen that when the electrolysis voltage in step (1) is within the range of 2 to 12 V, the gold leaching rate is relatively high. When the electrolysis voltage in step (1) is too high or too low, it will affect the gold leaching effect. Too high a voltage is likely to cause side reactions and increase energy consumption, while too low a voltage will result in insufficient reaction driving force, slower rate, uneven current distribution, etc. Therefore, controlling an appropriate voltage is crucial for the pretreatment effect and the subsequent gold leaching rate.

[0075] Examples 4 to 5 and Comparative Examples 3 to 4

[0076] Examples 4 to 5 and Comparative Examples 3 to 4 respectively provide a gold extraction method for carbonaceous refractory gold ore. Compared with Example 1, the difference lies in the electrolysis time in step (1). The corresponding electrolysis times for each example and comparative example are shown in Table 4. The other steps are substantially the same as those in Example 1 and will not be elaborated here.

[0077] Table 4 Electrolysis time in step (1) of Examples 4 to 5 and Comparative Examples 3 to 4

[0078]

[0079] The gold grades in the leaching residues of Examples 4 to 5 and Comparative Examples 3 to 4 were analyzed separately, and the calculated gold leaching rates are shown in Table 5 respectively.

[0080] Table 5 Gold leaching rates in Examples 4 to 5 and Comparative Examples 3 to 4

[0081]

[0082] From the gold leaching rates in Examples 4 to 5 and Comparative Examples 3 to 4, it can be seen that when the electrolysis time in step (1) is within 3 to 8 h, the gold leaching rate is relatively high. When the electrolysis time in step (1) is too short, it will affect the gold leaching effect, which is due to the poor pretreatment effect. Although the gold leaching effect is not much different from that in Example 1 when the electrolysis time is too long, it will increase energy consumption.

[0083] Examples 6 to 7 and Comparative Examples 5 to 6

[0084] Examples 6 to 7 and Comparative Examples 5 to 6 respectively provide a gold extraction method for carbonaceous refractory gold ore. Compared with Example 1, the difference lies in the gold leaching time in step (2). The corresponding gold leaching times for each example and comparative example are shown in Table 6. The other steps are substantially the same as those in Example 1 and will not be elaborated here.

[0085] Table 6 Gold leaching time in step (2) of Examples 6 to 7 and Comparative Examples 5 to 6

[0086]

[0087] Analyze the gold grade in the leaching residues in Examples 6-7 and Comparative Examples 5-6 respectively, and the calculated gold leaching rates are shown in Table 7 as follows.

[0088] Table 7 Gold Leaching Rates in Examples 6-7 and Comparative Examples 5-6

[0089]

[0090] It can be seen from the gold leaching rates in Examples 6-7 and Comparative Examples 5-6 that when the gold leaching time in step (2) is within 1-6 h, the gold leaching rate is relatively high. When the leaching time in step (2) is too short, it will affect the gold leaching effect, which is due to insufficient reaction and kinetic limitation. And when the leaching time is too long, it will not only increase the possibility of side reactions but also increase the energy consumption cost.

[0091] Comparative Example 7

[0092] This comparative example provides a gold extraction method for carbonaceous refractory gold ore. Compared with Example 1, the difference is that in step (1), the pH value of the pulp is directly adjusted to 2, and in step (2), the pH value is not adjusted. The other steps are substantially the same as those in Example 1 and will not be elaborated here.

[0093] Analyze the gold grade in the leaching residue before adding resin in this comparative example, and the calculated gold leaching rate is 93.06%; then analyze the gold grade in the filtrate after resin gold extraction is completed, and the obtained gold extraction rate is 82.39%.

[0094] It can be seen from the test results of Comparative Example 7 that the gold extraction effect is poor. Therefore, directly adjusting the pH value of the solution to 2 during pretreatment will have an adverse effect on the subsequent resin gold adsorption effect. This is because during the pretreatment electrolysis process, sulfides in the minerals will electrolyze to produce acid, further reducing the pH value of the solution. And too low pH value will protonate the resin functional groups, the resin structure may be damaged, and the adsorption capacity will decrease; H + competes with other cations for adsorption sites, and the adsorption kinetics slows down.

[0095] Comparative Example 8

[0096] This comparative example provides a gold extraction method for carbonaceous refractory gold ore. Compared with Example 1, the difference is that in step (1), the pH value of the pulp is directly adjusted to 2, and in step (2), sodium hydroxide is added to adjust the pH value of the pulp back to 2. The other steps are substantially the same as those in Example 1 and will not be elaborated here.

[0097] The gold grade in the tailings after the resin gold extraction was analyzed, and the gold leaching rate was 86.57%. This is because after the gold leaching, alkali is added to the leaching residue to adjust the pH value, which will cause the leached gold to re-precipitate and affect the gold leaching index.

[0098] In summary, the present application provides a method for extracting gold from carbonaceous and difficult-to-treat gold ores. The gold-robbing effect of carbonaceous minerals is eliminated by electrochemical pretreatment, and direct leaching of gold is achieved without solid-liquid separation, which significantly improves the recovery rate of gold in carbonaceous gold ores, and realizes the simultaneous development of carbonaceous gold ore pretreatment and leaching recovery processes. During the entire process, liquids are recycled to maximize resource utilization; tailings do not contain toxic and harmful substances, eliminating potential environmental pollution hazards; at the same time, no harmful waste gas is generated during the entire production process, which fully demonstrates the green and environmentally friendly characteristics of the process, which is in line with the current concept of sustainable development. In addition, by adjusting the pH value of the slurry in steps, while ensuring the removal of impurities such as carbon in the mineral, gold has a higher leaching rate. In the subsequent gold extraction process, it can be directly extracted by conventional resins, and has a higher extraction effect. The method has the advantages of simple equipment, short process, low reagent consumption, good environmental benefits and good metal recovery effect, and shows good application prospects in the treatment of carbonaceous gold ores.

[0099] 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 method for extracting gold from carbon-containing refractory gold ore, characterized in that: The following steps are involved: S1. Grind the carbonaceous gold ore, add it to the electrolytic cell, stir it evenly, add a first pH regulator to adjust the pH value of the slurry so that 2 < pH ≤ 7, and perform electrolytic pretreatment; S2. Continue to add anion exchange resin to the slurry, add a second pH adjuster to adjust the pH value of the slurry so that 1≤pH≤2, and stir to leaching gold; S3. Separate the gold-loaded resin from the ore pulp, circulate the tailings after purification and discharge the tailings after neutralization.

2. The method for extracting gold from carbon-containing refractory gold ore according to claim 1, characterized in that: In step S1, the voltage of the electrolysis is 2-12V, and the time of the electrolysis is 3-8h.

3. The method for extracting gold from carbon-containing refractory gold ore according to claim 1, characterized in that: In step S2, the stirring and leaching time is 1 to 6 hours.

4. The method for extracting gold from carbon-containing refractory gold ore according to claim 1, characterized in that: In step S1, the electrolyte in the electrolyte solution is one or a combination of any two of sodium chloride and / or potassium chloride, sodium bromide and / or potassium bromide, potassium iodide and / or sodium iodide; the mass concentration of the electrolyte is 20-200 g / L.

5. The method for extracting gold from carbon-containing refractory gold ore according to claim 1, characterized in that: In step S1, the fine grinding refers to the grinding fineness of -0.074mm accounting for 80% to 95%.

6. The method for extracting gold from carbon-containing refractory gold ore according to claim 1, characterized in that: In step S1, the mass concentration of the slurry in the electrolytic cell is 5% to 40%.

7. The method for extracting gold from carbon-containing refractory gold ore according to claim 1, characterized in that: In step S1, the first pH adjuster is hydrochloric acid.

8. The method for extracting gold from carbon-containing refractory gold ore according to claim 1, characterized in that: In step S2, the second pH adjuster is hydrochloric acid or sulfuric acid.

9. The method for extracting gold from carbon-containing refractory gold ore according to claim 1, characterized in that: In step S2, the anion exchange resin includes: YKTG01, YKTG04, D201, D201×7, XJZY resin; the addition amount of the anion exchange resin is 10-40 ml / L.

10. The method for extracting gold from carbon-containing refractory gold ore according to claim 1, characterized in that: In step S1, the material of the electrolytic cell is one of PP, fiberglass, PPH or PPR; the material of the anode of the electrolytic cell is one of graphite, ruthenium-plated titanium plate or ruthenium-plated titanium mesh, and the material of the cathode is one of titanium plate, titanium mesh or graphite.

Images