Method for recovering valuable metals and cyanide from cyanide tailings by means of pulse current diaphragm electrolysis

Abstract

The application provides a method for recovering valuable metals and cyanide in cyanide tail liquid based on pulse current diaphragm electrolysis, and belongs to the field of wastewater treatment, wherein a diaphragm electrolysis device is assembled to separate an anode chamber and a cathode chamber by an ion exchange membrane; an alkaline electrolyte solution is added into the anode chamber, and a cyanide tail liquid to be treated is added into the cathode chamber; a single pulse current is used for electrolysis reaction, and the cathode chamber is continuously aerated; after the reaction is completed, the cathode electrolyte is determined to calculate the cyanide recovery rate and the valuable metal recovery rate. The application can efficiently, lowly and selectively recover valuable metals in the cyanide tail liquid under alkaline conditions, and can effectively recover cyanide at the same time, overcomes the limitations of the traditional electrolysis method, and has important economic and environmental significance.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, specifically to a method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current diaphragm electrolysis. Background Technology

[0002] Cyanide is the most widely used gold extraction method in hydrometallurgy, but the cyanide tail liquor produced by this method usually contains highly toxic cyanides and heavy metal complexes. Direct discharge of this tail liquor will cause serious harm to the environment and ecosystem. Currently, the main methods for treating cyanide tail liquor include chemical oxidation, adsorption, and direct current electrolysis. Chemical oxidation can effectively destroy cyanide, but it usually cannot effectively recover valuable metals and may produce secondary pollution or consume large amounts of chemical reagents, resulting in high treatment costs. Adsorption is mainly used to recover precious metals such as gold, but its effectiveness in treating other metals and cyanides is limited, and adsorbent regeneration or subsequent treatment is complex. Direct current electrolysis involves applying a certain amount of direct current to simultaneously recover metals and destroy cyanide; however, traditional direct current electrolysis has the following problems: low current efficiency and high energy consumption for low-concentration tail liquor; easy electrode passivation, affecting treatment efficiency and electrode lifespan; severe hydrogen evolution side reaction at the cathode, reducing metal recovery efficiency; and the potential mixing of anode and cathode products, leading to reverse reactions or the formation of unwanted byproducts, such as cyanate (CNO) produced by anodizing. - It may migrate to the cathode region and affect metal deposition, or cyanide ions generated at the cathode may migrate to the anode and be over-oxidized.

[0003] In view of this, it is necessary to design a method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current diaphragm electrolysis to solve the above problems. Summary of the Invention

[0004] In view of the technical problems existing in the background technology, this application provides a method for recovering valuable metals and cyanides in cyanide tail liquid based on pulse current diaphragm electrolysis, which aims to solve the technical problems of low recovery rate of valuable metals under alkaline conditions, inability to recover cyanides simultaneously, high energy consumption, and easy passivation of electrodes in existing cyanide tail liquid treatment technologies.

[0005] This application provides a method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current diaphragm electrolysis, comprising the following steps:

[0006] S1. Assemble the diaphragm electrolysis device, separating the anode chamber and the cathode chamber with an ion exchange membrane;

[0007] S2. Add an alkaline electrolyte solution to the anode chamber and add the cyanide tailings to be treated to the cathode chamber;

[0008] S3. Electrolysis reaction is carried out using a single pulse current, and continuous aeration is provided to the cathode chamber;

[0009] S4. After the reaction is complete, the cathode electrolyte is measured, and the cyanide recovery rate and the valuable metal recovery rate are calculated.

[0010] As a further improvement of this application, the cathode of the diaphragm electrolysis device is one of graphite felt electrode, carbon felt electrode, stainless steel electrode, nickel foam electrode, and copper foam electrode.

[0011] As a further improvement of this application, the anode of the diaphragm electrolysis device is one of a titanium-iridium-tantalum electrode, a platinum-titanium electrode, a ruthenium-iridium-titanium electrode, or a tin-antimony-titanium electrode.

[0012] As a further improvement of this application, the parameters of the electrolysis reaction include: voltage 1~7V, current 0.4~2A, pulse frequency 50Hz~1kHz, duty cycle range 30~70%, and pulse width range 500~5000μs.

[0013] As a further improvement of this application, the electrolysis reaction time is 1 to 8 hours.

[0014] As a further improvement to this application, the aeration flow rate is 1~4 mL / min.

[0015] As a further improvement to this application, the ion exchange membrane is one of a cation exchange membrane, anion exchange membrane, or bipolar membrane.

[0016] As a further improvement of this application, the concentration of valuable metals in the cyanide tail liquid is 1000~5000ppm, and the concentration of cyanide is 1000~10000ppm.

[0017] As a further improvement to this application, the diaphragm electrolysis device includes a pulse power supply, a diaphragm electrolysis cell, and an aeration device.

[0018] The beneficial effects of this application are as follows:

[0019] This application provides a method for recovering valuable metals and cyanide from cyanide tailings using pulsed current diaphragm electrolysis. The method involves assembling a diaphragm electrolysis device, separating the anode and cathode chambers with an ion-exchange membrane; adding an alkaline electrolyte solution to the anode chamber and the cyanide tailings to be treated to the cathode chamber; conducting the electrolysis reaction using a single-pulse current while continuously aerating the cathode chamber; and measuring the cathode electrolyte after the reaction to calculate the cyanide recovery rate and the valuable metal recovery rate. This application develops a highly efficient, low-consumption, and selective technology for recovering valuable metals from cyanide tailings under alkaline conditions, while simultaneously and effectively recovering cyanide. This overcomes the limitations of traditional electrolysis methods and has significant economic and environmental implications.

[0020] Pulse electrolysis technology controls the current through a specific device, causing it to alternate periodically with a "current-off-current-off" cycle according to a preset pattern. This offers advantages such as improved mass transfer, increased current efficiency, and improved deposition quality. Diaphragm electrolysis technology effectively separates the anodic and cathodic regions, preventing product mixing and improving reaction selectivity and efficiency. Combining pulsed current with diaphragm electrolysis for cyanide tailings treatment overcomes the shortcomings of existing technologies, enabling the simultaneous recovery of valuable metals and cyanide, while also saving energy, reducing costs, and increasing efficiency.

[0021] This application utilizes a diaphragm material to effectively physically isolate the cathode and anode regions. The anode is an electrolyte solution for conduction, while the cathode is the cyanide tailings to be treated. This prevents product mixing between the cathode and anode regions, avoids the re-oxidation and dissolution of deposited valuable metals, inhibits cyanide ion oxidation, and improves the net yield and purity of the target product. By applying a single-pulse current, the ion concentration near the electrode interface is restored during the "power-off" period of the pulse power supply, thereby reducing concentration polarization, significantly improving the mass transfer process, and increasing the reaction efficiency at low concentrations, thus improving the recovery efficiency of valuable metals and cyanide. At the same time, pulse electrodeposition can result in finer metal deposition layer grains and better adhesion, which is beneficial for subsequent stripping and collection from the cathode, thereby improving the purity and value of the recovered metal and avoiding the loose, powdery or spongy deposition that often occurs in DC electrolysis. Furthermore, by optimizing pulse parameters (frequency, duty cycle, pulse width, etc.), the electrode potential and interfacial reaction environment can be more precisely controlled, suppressing the occurrence of side reactions such as hydrogen evolution at the cathode, suppressing electrode surface passivation, significantly reducing overall energy consumption, and saving electricity costs.

[0022] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of this application, the accompanying drawings used in this application will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without any creative effort.

[0024] Figure 1 This is a diagram of the diaphragm electrolysis device in an embodiment of this application;

[0025] Figure 2 This is a schematic diagram of a single-pulse current waveform in an embodiment of this application;

[0026] Figure 3This is an ICP diagram of the cyanide tail liquid to be treated in Example 1 of this application;

[0027] Figure 4 This is a SEM-EDS image of the cathode plate deposited in Example 1 of this application;

[0028] Figure 5 This is a physical image of the cathode plate after reaction in Example 1 of this application. Detailed Implementation

[0029] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0031] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0032] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0033] The highly toxic cyanide tail liquid produced by the cyanide process for gold extraction requires strict treatment. Existing methods each have their limitations: chemical oxidation destroys cyanide but makes it difficult to recover metals; adsorption focuses on the recovery of precious metals but is insufficient in cyanide treatment; direct current electrolysis can simultaneously treat cyanide and recover metals, but it suffers from problems such as low current efficiency, electrode passivation, hydrogen evolution side reactions, and reverse reactions caused by the mixing of products at the anode and cathode, which affect the treatment effect and energy consumption.

[0034] To address the technical problems of low recovery rate of valuable metals under alkaline conditions, inability to simultaneously recover cyanide, high energy consumption, and easy passivation of electrodes in existing cyanide tailings treatment technologies, this application provides a method for recovering valuable metals and cyanide from cyanide tailings based on pulsed current diaphragm electrolysis. By combining pulsed current with diaphragm electrolysis in cyanide tailings treatment, the method can achieve efficient, low-consumption, and selective recovery of valuable metals from cyanide tailings under alkaline conditions, while simultaneously and effectively recovering cyanide.

[0035] This application provides a method for recovering valuable metals and cyanides from cyanide tailings using pulsed current diaphragm electrolysis, comprising the following steps:

[0036] S1. Assemble the diaphragm electrolysis device, separating the anode chamber and the cathode chamber with an ion exchange membrane;

[0037] S2. Add an alkaline electrolyte solution to the anode chamber and add the cyanide tailings to be treated to the cathode chamber;

[0038] S3. Electrolysis reaction is carried out using a single pulse current, and continuous aeration is provided to the cathode chamber;

[0039] S4. After the reaction is complete, the cathode electrolyte is measured, and the cyanide recovery rate and the valuable metal recovery rate are calculated.

[0040] In the technical solution of this application embodiment, cyanide and metal are efficiently separated by ion exchange membrane. Pulsed current electrolysis reduces concentration polarization and improves current efficiency, while suppressing side reactions such as hydrogen evolution. Cathode aeration promotes the dissociation of metal cyanide complexes and accelerates the reduction and deposition of metal ions. At the same time, it prevents the cyanide from hydrolyzing due to excessively high pH in the cathode area. Through the synergistic regulation of electrochemical kinetics and mass transfer enhancement, the problem of simultaneous and efficient recovery of metal and cyanide in traditional cyanide tail liquid treatment is solved, which has both economic and environmental benefits.

[0041] Furthermore, in some embodiments, the cathode of the diaphragm electrolysis device is one of graphite felt electrode, carbon felt electrode, stainless steel electrode, nickel foam electrode, and copper foam electrode.

[0042] In the technical solution of this application embodiment, the cathode adopts an electrode material with high cost performance, which significantly reduces the system cost while ensuring the processing effect.

[0043] Furthermore, in some embodiments, the anode of the diaphragm electrolysis device is one of a titanium-iridium-tantalum electrode, a platinum-titanium electrode, a ruthenium-iridium-titanium electrode, or a tin-antimony-titanium electrode.

[0044] In the technical solution of this application embodiment, the anode adopts a titanium-based coated electrode with good oxygen evolution performance to ensure excellent corrosion resistance in the electrolyte, thereby ensuring the long-term stable and efficient operation of the entire electrolysis process and helping to improve the overall effect of metal recovery on the cathode side.

[0045] Furthermore, in some embodiments, the parameters of the electrolysis reaction include: voltage 1~7V, current 0.4~2A, pulse frequency 50Hz~1kHz, duty cycle range 30~70%, and pulse width range 500~5000μs.

[0046] In the technical solution of this application embodiment, by optimizing the voltage and current parameter settings of the pulse current, it directly acts on the electrode reaction process to improve the recovery efficiency of valuable metals and cyanides, thereby enhancing the overall processing performance; by optimizing the frequency of the pulse current, it synchronously regulates the transfer efficiency of reactants to the electrode interface and the activity and stability of the electrode surface, overcoming mass transfer limitations and mitigating adverse effects such as passivation, ultimately improving the comprehensive performance of valuable metal recovery and cyanide treatment; by optimizing the duty cycle of the pulse current, it precisely controls the current "on" time (t) within each pulse cycle. on ) and “off” time (t) off By determining the relative proportions of the effective electrochemical reaction time and the interfacial ion concentration / surface state recovery time, the optimal balance point can be found. This allows for the synergistic optimization of mass transfer efficiency, improvement of the current efficiency of the target reaction, reduction of overall energy consumption, and reduction of electrical costs while ensuring a certain processing rate. Furthermore, by optimizing the pulse width of the pulsed current, the depth of the electrochemical reaction during a single pulse and the subsequent "turn-off" time (t) can be precisely controlled. off The balance between the degree of recovery of the internal interface can be achieved by selecting an appropriate pulse width, which can effectively drive the deposition of valuable metals and the conversion of cyanide while avoiding severe concentration polarization caused by excessively long reaction time.

[0047] Furthermore, in some embodiments, the electrolysis reaction time is 1 to 8 hours.

[0048] In the technical solution of this application embodiment, by optimizing the diaphragm electrolysis reaction time, an optimal reaction endpoint is determined based on the processing target and the change law of current efficiency during electrolysis. This ensures the processing effect while maximizing equipment utilization, shortening the batch processing cycle, and reducing unit energy consumption, thereby achieving the economy and efficiency of the overall process.

[0049] Furthermore, in some embodiments, the aeration flow rate is 1~4 mL / min.

[0050] In the technical solution of this application embodiment, air or oxygen is introduced to promote the diffusion of ions in the solution, making it easier for ions to migrate from the bulk solution to the electrode surface, thereby accelerating the reaction rate. The aeration rate is controlled by a rotor flow meter, with a set value of 1~4 mL / min. If the aeration rate is too low, the recovery rate of valuable metals will be low; if the aeration rate is too high, the recovery rate of cyanide will decrease.

[0051] Furthermore, in some embodiments, the ion exchange membrane is one of a cation exchange membrane, anion exchange membrane, or bipolar membrane.

[0052] In the technical solution of this application embodiment, the presence of an ion exchange membrane avoids cross-contamination between the anode and cathode products and ensures the recovery rate of cyanide. The ion exchange membrane is preferably a bipolar membrane, which has a synchronous acid-base regulation function, automatically maintaining the pH balance between the cathode and anode chambers, preventing the re-oxidation and dissolution of deposited valuable metals, inhibiting cyanide ion oxidation, and improving the net yield and purity of the target product. The alkaline electrolyte solution is a sodium or potassium salt solution, which can significantly improve conductivity. The combination of an alkaline environment and pulse electrolysis improves the cyanide recovery rate while reducing side reactions.

[0053] Furthermore, in some embodiments, the concentration of valuable metals in the cyanide tail liquid is 1000~5000ppm, and the concentration of cyanide is 1000~10000ppm.

[0054] In the technical solution of this application embodiment, efficient treatment of cyanide tail liquid with a wide concentration range is achieved by pulsed current and diaphragm electrolysis.

[0055] like Figure 1 As shown, in some embodiments, the diaphragm electrolysis device further includes a pulse power supply, a diaphragm electrolysis cell, and an aeration device.

[0056] In the technical solution of this application embodiment, a dual-pulse power supply is used as the power supply device, and the pulse current has specific waveform parameters, such as... Figure 2 As shown, its output current can exhibit a periodic alternating change of "power on-power off-power on-power off" according to a preset pattern, T on T represents the energizing time, in μs; off The time represented by is the power outage time, in μs; T represents one cycle time, in μs. A diaphragm electrolytic cell includes an anode chamber, a cathode chamber, a cathode plate, an anode plate, and a diaphragm material.

[0057] The following are some specific embodiments. It should be noted that the embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they shall be performed in accordance with the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.

[0058] Example 1

[0059] This embodiment provides a method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current diaphragm electrolysis, including the following steps:

[0060] S1. Assemble the diaphragm electrolysis device, separating the anode chamber and the cathode chamber with an ion exchange membrane;

[0061] S2. Add 500 mL of alkaline electrolyte solution (20% NaOH solution) to the anode chamber to enhance conductivity, and add 500 mL of the cyanide tailings to be treated to the cathode chamber. ICP analysis of the cyanide tailings is as follows: Figure 3 As shown, the valuable substance is mainly zinc; a titanium-iridium-tantalum electrode is selected as the anode and a carbon felt electrode as the cathode, and the distance between the two electrode plates and the bipolar film is adjusted to 2.5 cm.

[0062] S3. Electrolysis was carried out using a single-pulse current with a voltage of 5.0V and a current of 1A, a pulse frequency of 250Hz, a duty cycle of 50%, a current duration and a rest time of 2000μs, and continuous aeration in the cathode chamber at a rate of 3mL / min. No external reagents or pH adjustment were required, and the reaction was carried out for 4 hours at room temperature.

[0063] S4. After the reaction is complete, the cathode electrolyte is measured, and the cyanide recovery rate and valuable metal recovery rate are calculated. These rates reach 96.6% and 90.3%, respectively, achieving highly efficient recovery of cyanide and valuable metals. The cathode plate products after the reaction are as follows: Figures 4 to 5 As shown in the SEM-EDS results, the cathode plate products mainly consist of four elements: Zn, Cu, C, and N. Among them, Zn has the highest content, indicating that valuable substances in the solution have been effectively recovered.

[0064] Based on formulas (1) and (2), the cathode current efficiency CE and unit energy consumption E were calculated. Compared with DC with the same applied current and voltage, the recovery rates of cyanide and valuable metals increased by 7.8% and 12%, respectively, the current efficiency increased by 38.1%, and the energy consumption decreased by 20 kWh·m³. -3 In the process of achieving efficient recycling of useful materials, a significant reduction in electricity costs can be achieved simultaneously, which aligns with the needs of green development.

[0065]

[0066] In the formula, n is the number of electrons transferred;

[0067] F is Faraday's constant;

[0068] c0 is the initial metal ion concentration, in mol / L;

[0069] c t The concentration of metal ions after the reaction is expressed in mol / L.

[0070] I is the current intensity, in A;

[0071] t is the electrolysis time, in hours;

[0072] M is the molar mass of the metal, in g / mol;

[0073] U is the slot voltage, in V;

[0074] V represents the volume of the liquid to be treated, in L.

[0075] Examples 2-3 and Comparative Examples 1-2

[0076] Examples 2-3 and Comparative Examples 1-2 respectively provide a method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current membrane electrolysis. Compared with Example 1, the only difference is the current and voltage, as shown in Table 1. Other experimental parameters and conditions are basically the same as those in Example 1, and will not be repeated here.

[0077] Examples 4-5 and Comparative Examples 3-4

[0078] Examples 4-5 and Comparative Examples 3-4 respectively provide a method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current membrane electrolysis. The only difference between these methods and Example 1 is the pulse frequency, as shown in Table 1. Other experimental parameters and conditions are basically the same as in Example 1 and will not be repeated here.

[0079] Examples 6-7 and Comparative Examples 5-6

[0080] Examples 6-7 and Comparative Examples 5-6 respectively provide a method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current diaphragm electrolysis. Compared with Example 1, the only difference is the duty cycle, as shown in Table 1. Other experimental parameters and conditions are basically the same as those in Example 1, and will not be repeated here.

[0081] Examples 8-9 and Comparative Examples 7-8

[0082] Examples 8-9 and Comparative Examples 7-8 respectively provide a method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current membrane electrolysis. Compared with Example 1, the only difference is the pulse width, as shown in Table 1. Other experimental parameters and conditions are basically the same as those in Example 1, and will not be repeated here.

[0083] Examples 10-11 and Comparative Examples 9-10

[0084] Examples 10-11 and Comparative Examples 9-10 respectively provide a method for recovering valuable metals and cyanides from cyanide tail liquid based on pulsed current diaphragm electrolysis. Compared with Example 1, the only difference is the electrolysis time, as shown in Table 1. Other experimental parameters and conditions are basically the same as those in Example 1, and will not be repeated here.

[0085] Comparative Example 11

[0086] Comparative Example 11 provides a method for recovering valuable metals and cyanide from cyanide tailings using pulsed current diaphragm electrolysis. The only difference from Example 1 is that no aeration was performed during the reaction process; other experimental parameters and conditions are essentially the same as in Example 1 and will not be repeated here. Calculations and analysis show that the cyanide recovery rate was 84.7%, and the valuable metal recovery rate was 45.4%, indicating that effective recovery of valuable metals was not achieved.

[0087] Comparative Example 12

[0088] Comparative Example 12 provides a method for recovering valuable metals and cyanide from cyanide tailings using pulsed current diaphragm electrolysis. The only difference from Example 1 is the use of a Ti electrode as the cathode plate. Calculations and analysis show that the cyanide recovery rate is 78.6%, and the valuable metal recovery rate is 56.9%, indicating that effective recovery of valuable metals was not achieved.

[0089] Table 1. Diaphragm electrolysis parameters and test results of the examples and comparative examples.

[0090]

[0091] Comparing Examples 1-3 and Comparative Examples 1-2, it can be seen that when the current and voltage are too low, the recovery rate of valuable metals is low, and the reaction effect is not ideal. When the current and voltage are too high, the desired effect can be achieved, but the power consumption is too high, the cost is too high, and the economic benefits are not suitable. Comparing Examples 4-5 and Comparative Examples 3-4, it can be seen that when the pulse frequency is too low, it is not conducive to the elimination of concentration polarization, thus leading to a decrease in the reaction effect. When the pulse frequency is too high, it will reduce the reaction rate, which is not conducive to the reaction. Comparing Examples 6-7 and Comparative Examples 5-6, it can be seen that when the duty cycle is too low, the effective time of the current is too short, thus leading to an unsatisfactory reaction effect. When the duty cycle is too high, the effect of reducing overall energy consumption and reducing power costs cannot be achieved. Comparing Examples 8-9 and Comparative Examples 7-8, it can be seen that when the pulse width is too small, the reaction will be incomplete, and the recovery effect of valuable metals will be poor. When the pulse width is too large, it is not conducive to the elimination of concentration polarization. Comparing Examples 10-11 and Comparative Examples 9-10, it is evident that a short electrolysis time leads to incomplete reaction and poor recovery of valuable metals, while a long electrolysis time increases energy consumption. Comparative Example 11 shows that without aeration during the reaction, the cyanide recovery rate was 84.7%, and the valuable metal recovery rate was 45.4%, failing to achieve effective recovery of valuable metals. Comparative Example 12 shows that using a Ti electrode as the cathode resulted in a cyanide recovery rate of 78.6% and a valuable metal recovery rate of 56.9%, also failing to achieve effective recovery of valuable metals.

[0092] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current diaphragm electrolysis, characterized in that, Includes the following steps: S1. Assemble the diaphragm electrolysis device, separating the anode chamber and the cathode chamber with an ion exchange membrane; S2. Add an alkaline electrolyte solution to the anode chamber and add the cyanide tailings to be treated to the cathode chamber; S3. Electrolysis is performed using a single-pulse current, and air or oxygen is continuously introduced into the cathode chamber for aeration. The parameters of the electrolysis reaction include: voltage 1~7V, current 0.4~2A, pulse frequency 50Hz~1kHz, duty cycle range 30~70%, and pulse width range 500~5000μs. The aeration flow rate is 1~4mL / min. S4. After the reaction is complete, the cathode electrolyte is measured, and the cyanide recovery rate and the valuable metal recovery rate are calculated.

2. The method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current diaphragm electrolysis according to claim 1, characterized in that, The cathode of the diaphragm electrolysis device is one of graphite felt electrode, carbon felt electrode, stainless steel electrode, nickel foam electrode, and copper foam electrode.

3. The method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current diaphragm electrolysis according to claim 2, characterized in that, The anode of the diaphragm electrolysis device is one of the following: titanium-iridium-tantalum electrode, platinum-titanium electrode, ruthenium-iridium-titanium electrode, and tin-antimony-titanium electrode.

4. The method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current diaphragm electrolysis according to claim 1, characterized in that, The electrolysis reaction takes 1 to 8 hours.

5. The method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current diaphragm electrolysis according to claim 1, characterized in that, The ion exchange membrane is one of a cation exchange membrane, anion exchange membrane, or bipolar membrane.

6. The method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current diaphragm electrolysis according to claim 1, characterized in that, The concentration of valuable metals in the cyanide tail liquid is 1000~5000ppm, and the concentration of cyanide is 1000~10000ppm.

7. The method for recovering valuable metals and cyanides from cyanide tailings based on pulsed current diaphragm electrolysis according to claim 1, characterized in that, The diaphragm electrolysis device includes a pulse power supply, a diaphragm electrolysis cell, and an aeration device.

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