A method for preparing thallium removal agent using zinc anode mud and the thallium removal agent.

Abstract

This invention discloses a method for preparing a thallium removal agent using zinc anode mud and the thallium removal agent itself, relating to the fields of chemical smelting and wastewater treatment technology. The method includes: mixing zinc anode mud with dilute sulfuric acid and / or zinc electrolysis waste liquid, then adding zinc sulfide concentrate and / or ferrous sulfide, reacting at 60℃~80℃ for 3h~5h, with a final acid concentration of 20g / L~30g / L, and filtering to obtain a leachate of low-valent manganese ferroalloy; introducing ozone into the low-valent manganese ferroalloy leachate, oxidizing at 70℃~80℃ for 60min~90min, adjusting the final pH to 3.0~5.0, and filtering to obtain a solid mixture containing manganese dioxide and ferric hydroxide; mixing the solid mixture with solid sodium hydroxide, and calcining at 550℃~600℃ for 1h~2h to obtain the thallium removal agent. This invention combines reduction leaching, oxidation precipitation, and calcination of zinc anode mud to obtain a thallium removal agent containing highly oxidizing permanganate and easily hydrolyzable adsorbent ferrate. This agent can be used for thallium removal in wastewater and heavy metal solutions, improving the utilization rate of zinc anode mud and realizing the resource utilization of zinc electrolysis intermediate slag.

Description

Technical Field

[0001] This invention relates to the field of chemical smelting and wastewater treatment technology, specifically to a method for preparing a thallium removal agent using zinc anode mud and the thallium removal agent itself. Background Technology

[0002] With the increasing scarcity of low-impurity, easily processed raw materials, some high-impurity, difficult-to-process zinc ores are gradually being used in production. The use of zinc ores with high thallium content can lead to an increase in thallium levels in the zinc smelting system. If proper circuit opening methods are not implemented, thallium accumulates within the system and gradually migrates to the electrolysis end, ultimately causing zinc precipitates to "burn," resulting in quality accidents and increased production costs. Therefore, thallium removal and circuit opening have become common problems in zinc smelting. Currently used thallium removal methods mainly include displacement, sulfidation, oxidation precipitation, and oxidation adsorption, with different methods employed for solutions or wastewater with varying thallium contents.

[0003] Zinc electrolysis anode mud (i.e., zinc anode mud) mainly contains valuable elements such as manganese and lead. It is estimated that about 50 kg of anode mud will be generated for every ton of zinc produced. During the electrolysis process, a small portion will naturally fall off from the anode into the electrolytic cell and be returned to the roasted sand leaching process as an oxidant. Most of it is manually stripped from the anode. Hydrometallurgical zinc plants generally treat this part of zinc electrolysis anode mud as lead slag and sell it externally, without recycling the valuable metals such as manganese. Some zinc smelters use the oxidizing and adsorbing properties of anode mud to remove thallium from the zinc smelting solution, but problems such as unstable thallium removal effect, large usage, low utilization rate, and easy blockage of pipes and tanks will occur. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0005] Therefore, this invention extracts effective components from zinc anode mud to prepare a thallium removal agent, which not only enables the resource utilization of zinc anode mud, but also solves the practical problem of thallium removal, thus having significant economic and environmental benefits.

[0006] In a first aspect, the present invention provides a method for preparing a thallium removal agent using zinc anode mud, comprising:

[0007] Reduction leaching: Zinc anode mud is mixed with dilute sulfuric acid and / or zinc electrolysis waste liquid, and then zinc sulfide concentrate and / or ferrous sulfide are added. The mixture is reacted at 60℃~80℃ for 3h~5h. After the reaction is completed, the acid concentration is 20g / L~30g / L. The solution is filtered to obtain low-valent manganese ferrochlore leachate.

[0008] Oxidation precipitation: Ozone is introduced into the low-valent manganese iron leaching solution, and the oxidation treatment is carried out at 70℃~80℃ for 60min~90min. The final pH is adjusted to 3.0~5.0, and the mixture is filtered to obtain a solid mixture containing manganese dioxide and iron hydroxide.

[0009] Calcination: The solid mixture containing manganese dioxide and iron hydroxide is mixed with solid sodium hydroxide and calcined at 550℃~600℃ for 1h~2h to obtain thallium removal agent.

[0010] Furthermore, the reduction leaching also includes:

[0011] The zinc anode mud is ball-milled to a particle size of -200 mesh ≥80%, and then mixed with the dilute sulfuric acid and / or the zinc electrolytic waste liquid.

[0012] Furthermore, the reduction leaching also includes:

[0013] The liquid-to-solid ratio of the zinc anode mud to the dilute sulfuric acid and / or the zinc electrolytic waste liquid is 3-5:1, the concentration of the dilute sulfuric acid is 160g / L-200g / L, and the concentration of the zinc electrolytic waste liquid is 160g / L-200g / L.

[0014] Furthermore, the reduction leaching also includes:

[0015] The amount of zinc sulfide concentrate and / or ferrous sulfide added is 1.1 to 1.2 times the theoretical molar amount.

[0016] Furthermore, in the oxidative precipitation, the endpoint pH is adjusted to 3.0–5.0 using sodium hydroxide and / or sodium carbonate.

[0017] Further, the oxidation precipitation is carried out by introducing ozone into the low-valent manganese iron leaching solution, oxidizing it at 70℃~72℃ for 80min~90min, adjusting the final pH to 4.5~5.0, and filtering to obtain the solid mixture containing manganese dioxide and iron hydroxide.

[0018] Further, the calcination is performed by mixing the solid mixture containing manganese dioxide and iron hydroxide with solid sodium hydroxide and calcining it at 580℃~600℃ for 1.5h~2h to obtain the thallium removal agent.

[0019] In a second aspect, the present invention provides a thallium removal agent, which is prepared by the above-described method of preparing a thallium removal agent using zinc anode mud.

[0020] Furthermore, the thallium removal method of the thallium removal agent includes:

[0021] The thallium removal agent is added to the thallium-containing solution to adjust the pH of the thallium-containing solution to be not lower than 3.0. The dosage of the thallium removal agent is 4 g / L to 6 g / L, and the thallium removal reaction time is not less than 30 min.

[0022] Furthermore, when the dosage of the thallium removal agent is 5 g / L, the thallium removal rate reaches over 97%.

[0023] The method for preparing thallium removal agent using zinc anode mud provided by the present invention has at least the following advantages compared with the prior art:

[0024] 1. By using processes such as reduction leaching, oxidation precipitation and calcination, manganese in zinc anode mud is gradually extracted and converted into high-valence manganate, realizing the resource utilization and harmless use of manganese in zinc anode mud.

[0025] 2. By adding zinc sulfide concentrate and / or ferrous sulfide during the reduction leaching of zinc anode mud, high-valence manganese can be extracted without introducing impurities harmful to zinc smelting. At the same time, the iron element in zinc sulfide concentrate or ferrous sulfide can be fully utilized. During the extraction and conversion of manganese, iron is simultaneously converted into ferrates. The final thallium removal agent product contains highly oxidizing permanganate and easily hydrolyzed ferrates with adsorption properties. The thallium removal mechanism of this thallium removal agent is the principle of oxidation adsorption.

[0026] 3. The raw materials used are readily available, all of which are raw materials and intermediate materials for zinc smelting. The slag produced can be returned to the zinc system for treatment. No waste is generated during the process. The resulting thallium removal agent can be used in the thallium removal process of zinc smelting wastewater, which has significant economic and environmental benefits. Attached Figure Description

[0027] Figure 1 This is a process flow diagram of preparing thallium removal agent using zinc anode mud, as provided in Embodiment 1 of the present invention. Detailed Implementation

[0028] To better understand the above technical solutions, the technical solutions of the embodiments of this application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of this application and the specific features in the embodiments are detailed descriptions of the technical solutions of the embodiments of this application, rather than limitations on the technical solutions of this application. In the absence of conflict, the embodiments of this application and the technical features in the embodiments can be combined with each other.

[0029] A first aspect of the present invention provides a method for preparing a thallium removal agent using zinc anode mud, comprising:

[0030] S1 Reduction Leaching: Zinc anode mud is mixed with dilute sulfuric acid and / or zinc electrolysis waste liquid, and then zinc sulfide concentrate and / or ferrous sulfide are added. The mixture is reacted at 60℃~80℃ for 3h~5h. The acid concentration at the end of the reaction is 20g / L~30g / L. The solution is filtered to obtain low-valent manganese ferrochlore leachate.

[0031] S2 Oxidation Precipitation: Ozone is introduced into the low-valent manganese iron leaching solution, and the oxidation treatment is carried out at 70℃~80℃ for 60min~90min. The final pH is adjusted to 3.0~5.0, and the mixture is filtered to obtain a solid mixture containing manganese dioxide and iron hydroxide.

[0032] S3 Calcination: The solid mixture containing manganese dioxide and iron hydroxide is mixed with solid sodium hydroxide and calcined at 550℃~600℃ for 1h~2h to obtain thallium removal agent.

[0033] The method for preparing thallium removal agent using zinc anode mud provided in this invention has the following beneficial effects:

[0034] 1. By employing reduction leaching, oxidation precipitation, and calcination processes in zinc anode mud, manganese is gradually extracted and converted into high-valent manganate, achieving resource utilization and harmless treatment of manganese in the zinc anode mud. 2. During the reduction leaching of zinc anode mud, zinc sulfide concentrate and / or ferrous sulfide are added. Without introducing impurities harmful to zinc smelting, high-valent manganese is extracted through reduction, while iron in the zinc sulfide concentrate or ferrous sulfide is fully utilized. During the extraction and conversion of manganese, iron is simultaneously converted into ferrate. The final thallium removal agent contains highly oxidizing permanganate and easily hydrolyzed, adsorbent ferrate. The thallium removal mechanism of this agent is based on oxidation adsorption. 3. The raw materials used are readily available, all being raw materials and intermediate materials from zinc smelting. The generated slag can be returned to the zinc system for treatment, with no waste generated during the process. The resulting thallium removal agent can be used in the thallium removal process of zinc smelting wastewater, demonstrating significant economic and environmental benefits.

[0035] In the technical solution of this invention, manganese from zinc electrolysis anode mud and iron from zinc sulfide concentrate and / or ferrous sulfide are utilized to obtain a thallium removal agent with strong oxidizing and adsorption properties through reduction, oxidation, and calcination. The process is simple, and the thallium removal effect is good after application. The main chemical reactions that occur in the process include:

[0036] MnO₂ + 4NaOH + O₂ = Na₂MnO₄ + 2H₂O

[0037] Fe₂O₃ + 6NaOH = Na₃[Fe(OH)₆]

[0038] In some embodiments, the reductive leaching further includes:

[0039] The zinc anode mud is ball-milled to a particle size of -200 mesh ≥80%, and then mixed with the dilute sulfuric acid and / or the zinc electrolytic waste liquid.

[0040] Understandably, zinc anode mud is generally in the form of layers and has a relatively hard texture. In order to accelerate its reaction with dilute sulfuric acid and ensure that the effective components react fully, it needs to be ball-milled to a density of over 80% at -200 mesh.

[0041] In some embodiments, the reductive leaching further includes:

[0042] The liquid-to-solid ratio of the zinc anode mud to the dilute sulfuric acid and / or the zinc electrolytic waste liquid is 3-5:1, the concentration of the dilute sulfuric acid is 160g / L-200g / L, and the concentration of the zinc electrolytic waste liquid is 160g / L-200g / L.

[0043] Specifically, the concentration of manganese sulfate in the leachate is controlled by adjusting the liquid-to-solid ratio of the zinc anode mud to dilute sulfuric acid. If the liquid-to-solid ratio is higher than 5:1, the concentration of manganese sulfate is too low, which affects the efficiency of subsequent oxidation precipitation. If the liquid-to-solid ratio is lower than 3:1, the concentration of manganese sulfate in the leachate is too high, which affects the leaching rate and leaching percentage of the zinc anode mud in the reduction leaching process.

[0044] The choice of a dilute sulfuric acid concentration of 160g / L to 200g / L is primarily to match the concentration of the zinc electrolysis waste solution. This allows the zinc electrolysis waste solution containing 160g / L to 200g / L of acid to be directly used instead of dilute sulfuric acid, reducing the amount of sulfuric acid used. Understandably, lower or higher concentrations of sulfuric acid could also be used, but this would increase the amount of sulfuric acid used and the preparation process, making direct substitution with zinc electrolysis waste solution impossible and increasing costs.

[0045] In some embodiments, the reductive leaching further includes:

[0046] The amount of zinc sulfide concentrate and / or ferrous sulfide added is 1.1 to 1.2 times the theoretical molar amount.

[0047] Understandably, experiments have shown that reduction leaching is better when the amount of zinc sulfide concentrate and / or ferrous sulfide added is 1.1 to 1.2 times the theoretical molar amount.

[0048] In some embodiments, during the oxidative precipitation, the endpoint pH is adjusted to 3.0–5.0 using sodium hydroxide and / or sodium carbonate.

[0049] Specifically, after the oxidation treatment is completed, the high-valence manganese ions precipitate in the form of manganese dioxide. It is necessary to adjust the final pH value of the solution to 3.0 to 5.0. Within this pH range, the high-valence iron ions hydrolyze to form ferric hydroxide precipitate.

[0050] It is understandable that S1 reduction leaching is the leaching process of zinc anode mud, which only affects the leaching rate of manganese in the zinc anode mud. Our experiments summarized the optimal parameters for S1 reduction leaching as follows: mix zinc anode mud with dilute sulfuric acid and / or zinc electrolysis waste liquid, then add zinc sulfide concentrate and / or ferrous sulfide, react at 70℃ for 4 hours, the acid concentration at the end of the reaction is 30 g / L, the liquid-to-solid ratio of zinc anode mud to dilute sulfuric acid and / or zinc electrolysis waste liquid is 5:1, and the amount of zinc sulfide concentrate or ferrous sulfide added is 1.2 times the theoretical molar amount. The key steps affecting the thallium removal agent's effectiveness are the preparation process of the solid mixture containing manganese dioxide and ferric hydroxide in S2 oxidation precipitation and the calcination process in step S3. Therefore, below, we focus on optimizing the process parameters of S2 oxidation precipitation and S3 calcination.

[0051] Preferably, the oxidation precipitation is carried out by introducing ozone into the low-valent manganese iron leaching solution, oxidizing it at 70℃~72℃ for 80min~90min, adjusting the final pH to 4.5~5.0, and filtering to obtain the solid mixture containing manganese dioxide and iron hydroxide.

[0052] In this technical solution, ozone is a strong oxidant capable of oxidizing low-valent manganese and low-valent iron ions in the solution. In the S2 oxidation precipitation step, low-valent manganese ions are oxidized to high-valent manganese ions, and divalent iron ions are oxidized to trivalent iron ions. The reaction temperature is chosen to be between 70℃ and 80℃ because ozone is a gas, and its solubility in water decreases with increasing temperature. Below 70℃, although the solubility of ozone is relatively high, its reaction rate with metal ions is very low, which is not conducive to the oxidation process and results in fewer effective components. Above 80℃, although the reaction rate of ozone with metal ions increases, its solubility in water is very low, and the reduced effective concentration affects the reaction efficiency, which is not conducive to the oxidation process. Considering all factors, the preferred temperature is 70℃ to 72℃. The oxidation treatment time for the solution is 60-90 minutes. If the reaction time is less than 60 minutes, the low-valent manganese and iron ions will not react completely, resulting in a low content of effective components in the oxidation precipitation product, affecting the effectiveness of the thallium removal agent. If the reaction time is more than 90 minutes, the low-valent manganese and iron ions have completely converted to their high-valent states, and continuing to introduce ozone will waste ozone and increase preparation costs. Considering all factors, the optimal oxidation treatment time is 80-90 minutes. After the oxidation treatment, the high-valent manganese ions precipitate as manganese dioxide. The final pH value of the solution needs to be adjusted to allow the high-valent iron ions to hydrolyze and form iron hydroxide precipitate; the preferred final pH value is 4.5-5.0. Through the synergistic control of the entire oxidation precipitation process, a solid mixture containing manganese dioxide and iron hydroxide can be efficiently extracted from the low-valent manganese iron leachate. See Table 1 for details. Table 1 examines the effect of different parameters of S2 oxidation precipitation on the thallium removal rate of the thallium removal agent. For S1 leaching, the liquid-solid ratio of zinc anode mud to dilute sulfuric acid and / or zinc electrolysis waste liquid is 5:1, the amount of zinc sulfide concentrate or ferrous sulfide added is 1.2 times the theoretical molar amount, the reaction is carried out at 70℃ for 4 hours, and the acid concentration at the end of the reaction is 30 g / L. For S3 calcination, the calcination is carried out at 600℃ for 1.5 hours. As shown in Table 1, within the oxidation precipitation temperature range of 70–85℃, the thallium removal rate decreases with increasing temperature. At 70℃, the thallium removal rate reaches 92.58%, and at 65℃, it reaches 89.64%. Within the oxidation precipitation time range of 50–90 min, the thallium removal rate increases with increasing time. At 80 min, the thallium removal rate reaches 92.58%. Further extending the time to 90 min results in a smaller increase in the thallium removal rate, and further extending the time to 100 min does not increase the thallium removal rate further. Within the oxidation precipitation pH range of 2.0–6.0, the thallium removal rate increases with increasing pH. At pH 5.0, the thallium removal rate reaches 92.58%. However, at pH 6, zinc hydrolysis and precipitation lead to losses; therefore, a pH of 3–5 is preferred, with pH 4.5–5 being the optimal range. Therefore, the optimal conditions for oxidation precipitation are a temperature of 70℃, a time of 80 min, and a pH of 5.0.

[0053] Table 1. Effects of different temperatures, times, and pH values ​​on the thallium removal rate of the prepared thallium removal agent during oxidation precipitation treatment (the dosage of the thallium removal agent used for thallium removal from thallium-containing solutions is 3 g / L).

[0054] Temperature ℃ time min pH value Thallium removal rate % 65 80 5 89.64 70 80 5 92.58 75 80 5 86.55 80 80 5 79.10 85 80 5 70.03 70 50 5 72.48 70 60 5 78.02 70 70 5 84.73 70 80 5 92.58 70 90 5 92.77 70 100 5 92.72 70 80 2 65.37 70 80 3 84.91 70 80 4 89.06 70 80 5 92.58 70 80 6 92.61

[0055] Preferably, the calcination is performed by mixing the solid mixture containing manganese dioxide and iron hydroxide with solid sodium hydroxide and calcining it at 580℃~600℃ for 1.5h~2h to obtain the thallium removal agent.

[0056] In this technical solution, a solid mixture containing manganese dioxide and ferric hydroxide, obtained by S2 oxidation precipitation, is mixed with solid sodium hydroxide and calcined at 550℃~600℃ for 1h~2h to obtain a thallium removal agent. If the calcination temperature is below 550℃, the content of the effective components formed by manganese dioxide, ferric hydroxide, and sodium hydroxide is too low, affecting the effectiveness of the thallium removal agent. If the calcination temperature is above 600℃, the energy required for the reaction between manganese dioxide, ferric hydroxide, and sodium hydroxide is sufficient; further increasing the temperature will waste energy, and high temperatures may cause the effective components to decompose again, affecting the effectiveness of the thallium removal agent. If the calcination time is less than 1h, the reaction between manganese dioxide, ferric hydroxide, and sodium hydroxide is insufficient, resulting in an inadequate content of effective components. If the calcination time is more than 2h, the reaction between manganese dioxide, ferric hydroxide, and sodium hydroxide is complete; further extending the calcination time will lead to energy waste and have little effect on increasing the content of effective components. For details, please refer to our optimization of the process parameters of the S3 calcination process, as shown in Table 2. Table 2 examines the influence of different parameter conditions of the S3 calcination process on the thallium removal rate of the thallium removal agent. For the S1 leaching conditions, the liquid-solid ratio of zinc anode mud to dilute sulfuric acid and / or zinc electrolysis waste liquid is 5:1, the amount of zinc sulfide concentrate or ferrous sulfide added is 1.2 times the theoretical molar amount, the reaction is carried out at 70℃ for 4 hours, and the acid concentration at the end of the reaction is 30 g / L. For the S2 oxidation precipitation conditions, the oxidation treatment is carried out at 70℃ for 80 minutes, and the final pH is adjusted to 5.0. As shown in Table 2, within the calcination temperature range of 530–620℃, the thallium removal rate increases with increasing calcination temperature. After 580℃, the upward trend slows down, and the thallium removal rate reaches 92.58% at 600℃. Within the calcination time range of 0.5–2.5 h, the thallium removal rate increases with increasing calcination time. After 1.5 h, the upward trend slows down, and the thallium removal rate reaches 92.58% at 1.5 h. Therefore, the optimal conditions for calcination treatment are a temperature of 600℃ and a time of 1.5 h.

[0057] Table 2. Effect of different temperatures and times during calcination on the thallium removal rate of the prepared thallium removal agent (the dosage of the thallium removal agent used for thallium removal from thallium-containing solutions is 3 g / L).

[0058]

[0059]

[0060] In a second aspect, the present invention provides a thallium removal agent, which is prepared by the above-described method of preparing a thallium removal agent using zinc anode mud.

[0061] Specifically, the thallium removal method of the thallium removal agent includes: adding the thallium removal agent to a thallium-containing solution, adjusting the pH of the thallium-containing solution to be not lower than 3.0, using 4 g / L to 6 g / L of the thallium removal agent, and conducting a thallium removal reaction for not less than 30 minutes. Furthermore, when the amount of the thallium removal agent is 5 g / L, the thallium removal rate reaches over 97%.

[0062] Specifically, the thallium removal agent prepared in this application is suitable for thallium-containing solutions with a pH not lower than 3.0, and there is no upper limit requirement for the pH. For thallium-containing solutions or wastewater from zinc smelting, the pH is generally controlled at around 5.

[0063] Example 1: A method for preparing a thallium removal agent using zinc anode mud and the application of the obtained thallium removal agent.

[0064] See Figure 1 As shown, a method for preparing a thallium removal agent using zinc anode mud includes the following steps:

[0065] S1 Reduction Leaching: After ball milling, the zinc electrolytic anode mud has a particle size of -200 mesh (80%). It is mixed with 160 g / L dilute sulfuric acid at a liquid-to-solid ratio of 5:1. Zinc sulfide concentrate or ferrous sulfide, which is 1.2 times the theoretical molar amount of manganese and iron reduction, is added. The mixture is reacted at 70℃ for 4 hours, resulting in a final acid concentration of 30 g / L. The leachate is obtained by filtration and is a low-valence manganese-iron leachate. The leachate residue is sent to a volatilization kiln for treatment.

[0066] S2 Oxidation Precipitation: Ozone is introduced into the low-valent manganese iron leaching solution obtained in S1 for oxidation at a temperature of 70℃ for 80 min. The final pH is adjusted to 5 with sodium hydroxide or sodium carbonate. The solution is filtered to obtain a solid mixture containing manganese dioxide and iron hydroxide. The filtrate is then sent for zinc calcination leaching.

[0067] S3 calcination: The solid mixture containing manganese dioxide and iron hydroxide obtained in S2 is mixed with solid sodium hydroxide and calcined at 600°C for 1.5 hours. The mixture is then ground to obtain the thallium removal agent product.

[0068] The thallium removal effect of the thallium removal agent product obtained in Example 1 is evaluated below. The thallium removal agent prepared by the method of this application is generally suitable for solutions or wastewater with a pH of 3.0 or higher. For solutions or wastewater with a pH that does not meet the requirements, the pH can be adjusted to the specified range. The thallium removal agent can be directly added to the solution or wastewater to be treated. The cadmium-poor solution is a solution obtained after leaching and zinc powder replacement of cadmium slag from zinc smelting. It contains thallium as high as 150-200 mg / L, making it a representative high-thallium solution. As shown in Tables 3 and 4, the self-prepared solution, an aqueous solution simulating the thallium content of a cadmium-poor solution, exhibited a thallium removal rate that increased with the dosage of the thallium removal agent under the conditions of pH 4.5 and a reaction time of 30 min. The removal rate reached 97.45% when the dosage was 5 g / L. Similarly, for the actual solution (cadmium-poor solution), under the same conditions of pH 4.5 and a reaction time of 30 min, the thallium removal rate increased with the dosage of the thallium removal agent, reaching 98.77% when the dosage was 5 g / L. To achieve a better thallium removal effect, the dosage of the thallium removal agent is best within the range of 4–6 g / L.

[0069] Table 3 shows the thallium removal effect of the thallium scavenger prepared in Example 1 on self-prepared thallium-containing solutions.

[0070]

[0071] Table 4 shows the thallium removal effect of the thallium removal agent prepared in Example 1 on the production solution (cadmium-poor solution).

[0072]

[0073] It will be readily understood by those skilled in the art that the above-described advantageous methods can be freely combined and superimposed without conflict. The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application. The above are merely preferred embodiments of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this application, and these improvements and modifications should also be considered within the protection scope of this application.

Claims

1. A method for preparing a thallium removal agent using zinc anode mud, characterized in that, include: Reduction leaching: Zinc anode mud is mixed with dilute sulfuric acid and / or zinc electrolysis waste liquid, and then zinc sulfide concentrate and / or ferrous sulfide are added. The mixture is reacted at 60℃~80℃ for 3h~5h. After the reaction is completed, the acid concentration is 20g / L~30g / L. The solution is filtered to obtain low-valent manganese ferrochlore leachate. Oxidation precipitation: Ozone is introduced into the low-valent manganese iron leaching solution, and the oxidation treatment is carried out at 70℃~80℃ for 60min~90min. The final pH is adjusted to 3.0~5.0, and the mixture is filtered to obtain a solid mixture containing manganese dioxide and iron hydroxide. Calcination: The solid mixture containing manganese dioxide and iron hydroxide is mixed with solid sodium hydroxide and calcined at 550℃~600℃ for 1h~2h to obtain thallium removal agent.

2. The method for preparing thallium removal agent using zinc anode mud according to claim 1, characterized in that, The reduction leaching also includes: The zinc anode mud is ball-milled to a particle size of -200 mesh ≥80%, and then mixed with the dilute sulfuric acid and / or the zinc electrolytic waste liquid.

3. The method for preparing thallium removal agent using zinc anode mud according to claim 1, characterized in that, The reduction leaching also includes: The liquid-to-solid ratio of the zinc anode mud to the dilute sulfuric acid and / or the zinc electrolytic waste liquid is 3-5:1, the concentration of the dilute sulfuric acid is 160g / L-200g / L, and the concentration of the zinc electrolytic waste liquid is 160g / L-200g / L.

4. The method for preparing thallium removal agent using zinc anode mud according to claim 1, characterized in that, The reduction leaching also includes: The amount of zinc sulfide concentrate and / or ferrous sulfide added is 1.1 to 1.2 times the theoretical molar amount.

5. The method for preparing thallium removal agent using zinc anode mud according to claim 1, characterized in that, In the oxidative precipitation process, the endpoint pH is adjusted to 3.0–5.0 using sodium hydroxide and / or sodium carbonate.

6. The method for preparing thallium removal agent using zinc anode mud according to claim 5, characterized in that, The oxidation precipitation is achieved by introducing ozone into the low-valent manganese iron leaching solution, oxidizing it at 70℃~72℃ for 80min~90min, adjusting the final pH to 4.5~5.0, and filtering to obtain the solid mixture containing manganese dioxide and iron hydroxide.

7. The method for preparing thallium removal agent using zinc anode mud according to claim 1, characterized in that, The calcination is performed by mixing the solid mixture containing manganese dioxide and iron hydroxide with solid sodium hydroxide and calcining it at 580℃~600℃ for 1.5h~2h to obtain the thallium removal agent.

8. A thallium removal agent, characterized in that, It is prepared by the method of preparing thallium removal agent using zinc anode mud as described in any one of claims 1 to 7.

9. The thallium removal agent according to claim 8, characterized in that, The thallium removal method of the thallium scavenger includes: The thallium removal agent is added to the thallium-containing solution to adjust the pH of the thallium-containing solution to be not lower than 3.

0. The amount of the thallium removal agent is 4 g / L to 6 g / L, and the thallium removal reaction time is not less than 30 min.

10. The thallium removal agent according to claim 9, characterized in that, When the dosage of the thallium removal agent is 5 g / L, the thallium removal rate reaches over 97%.

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