Method for preparing thallium removal agent from zinc anode slime and thallium removal agent

Abstract

The invention discloses a method for preparing a thallium removal agent from zinc anode slime and the thallium removal agent, and relates to the technical field of chemical smelting and wastewater treatment. Comprising the steps that the zinc anode slime is mixed with dilute sulphuric acid and / or zinc electrolysis waste liquid, then zinc sulfide concentrate and / or ferrous sulfide are / is added, a reaction is conducted for 3-5 h at the temperature of 60-80 DEG C, the final acid is 20-30 g / L, and a low-valence ferromanganese leaching solution is obtained through filtering; ozone is introduced into the low-valence ferromanganese leachate, oxidation treatment is carried out for 60 min to 90 min at the temperature of 70 DEG C to 80 DEG C, the end point pH is adjusted to be 3.0 to 5.0, and a solid mixture containing manganese dioxide and ferric hydroxide is obtained through filtering; and uniformly mixing the solid mixture with a sodium hydroxide solid, and calcining at 550-600 DEG C for 1-2 hours to obtain the thallium removal agent. According to the method, reduction leaching, oxidation precipitation and calcination of the zinc anode slime are combined, the thallium removal agent containing permanganate with strong oxidizing property and ferrate which is easy to hydrolyze and has adsorbability is obtained, the thallium removal agent can be used for removing thallium in wastewater and heavy metal solutions, the utilization rate of the zinc anode slime is increased, and resource utilization of the zinc electrolysis intermediate slag is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of chemical smelting and wastewater treatment, and in particular to a method for preparing a thallium removing agent by utilizing zinc anode mud and the thallium removing agent. Background Art

[0002] With the increasing shortage of low-impurity and easy-to-handle raw materials, some high-impurity and difficult-to-handle zinc ores are gradually put into production. Among them, zinc ores with high thallium content will increase the thallium in the zinc smelting system after use. If the open circuit means are not strengthened, thallium will accumulate inside the system and gradually migrate to the electrolysis end, eventually leading to the precipitation of zinc "burned plate", causing quality accidents and increasing production costs. Therefore, thallium removal and open circuit have become common problems in zinc smelting. The currently used thallium removal methods mainly include replacement method, sulfidation method, oxidation precipitation method, oxidation adsorption method, etc. Different methods are used to treat solutions or wastewater with different 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 produced for every ton of zinc produced. During the electrolysis process, a small part of it naturally falls off from the anode into the electrolytic cell and returns to the roasting sand leaching process with the solution for use as an oxidant. Most of it is manually peeled off from the anode. Hydrometallurgical zinc smelting plants generally treat this part of zinc electrolysis anode mud as lead slag for sale, and do not recycle valuable metals such as manganese. Some zinc smelters use anode mud to remove thallium from zinc smelting solution using the oxidizing and adsorptive properties of anode mud. However, there will be problems such as unstable thallium removal effect, large usage, low utilization rate, and easy blockage of pipelines and tanks. 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, the present invention extracts effective components from zinc anode mud to prepare thallium removal agent, which not only makes zinc anode mud resource utilization, but also solves the practical problem of thallium removal, and has important 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: 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 60℃~80℃ for 3h~5h, the acid concentration is 20g / L~30g / L at the end of the reaction, filter to obtain the leaching solution of low-valent manganese iron;

[0008] Oxidation precipitation: introducing ozone into the low-valent ferromanganese leaching solution, oxidizing at 70° C. to 80° C. for 60 min to 90 min, adjusting the end point pH to 3.0 to 5.0, and filtering to obtain a solid mixture containing manganese dioxide and ferric hydroxide;

[0009] Calcination: The solid mixture containing manganese dioxide and ferric hydroxide is mixed with solid sodium hydroxide, and calcined at 550° C. to 600° C. for 1 h to 2 h to obtain a thallium removal agent.

[0010] Furthermore, the reduction leaching further comprises:

[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 electrolysis waste liquid.

[0012] Furthermore, the reduction leaching further comprises:

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

[0014] Furthermore, the reduction leaching further comprises:

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

[0016] Furthermore, in the oxidation precipitation, sodium hydroxide and / or sodium carbonate are used to adjust the end point pH to 3.0-5.0.

[0017] Furthermore, the oxidation precipitation is to introduce ozone into the low-valent manganese iron leaching solution, perform oxidation treatment at 70°C to 72°C for 80min to 90min, adjust the end point pH to 4.5 to 5.0, and filter to obtain the solid mixture containing manganese dioxide and ferric hydroxide.

[0018] Furthermore, the calcination is to mix the solid mixture containing manganese dioxide and iron hydroxide with solid sodium hydroxide, and calcine at 580° C. to 600° C. for 1.5 h to 2 h to obtain the thallium removal agent.

[0019] The second aspect of the present invention provides a thallium removing agent, which is prepared by the above-mentioned method for preparing the thallium removing agent by using zinc anode mud.

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

[0021] The thallium removal agent is added to the thallium-containing solution, and the pH of the thallium-containing solution is adjusted to be not less 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 minutes.

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

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

[0024] 1. The manganese element in zinc anode mud is gradually extracted and converted into high-valent manganate by using reduction leaching, oxidation precipitation and calcination processes, thus realizing the resource utilization and harmless utilization of manganese element in zinc anode mud.

[0025] 2. When zinc anode mud is added with zinc sulfide concentrate and / or ferrous sulfide during reduction leaching, high-valent manganese can be reduced and extracted without introducing impurities harmful to zinc smelting, and 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 ferrite. The final thallium removal agent product contains highly oxidizing permanganate and easily hydrolyzed ferrite with adsorption. The thallium removal mechanism of the thallium removal agent is the principle of oxidation adsorption.

[0026] 3. The raw materials used are easy to obtain, 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 three wastes are produced in the process. The obtained thallium removal agent product can be used in the thallium removal process of zinc smelting wastewater, which has obvious economic and environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a process flow chart for preparing a thallium removal agent using zinc anode mud provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0028] In order to better understand the above-mentioned technical scheme, the technical scheme of the embodiments of the present application is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical scheme of the embodiments of the present application, rather than limitations on the technical scheme of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments may be combined with each other.

[0029] A first aspect of an embodiment 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, and the reaction is carried out at 60℃~80℃ for 3h~5h. The acid concentration is 20g / L~30g / L at the end of the reaction, and the low-valent ferromanganese leaching solution is obtained by filtration;

[0031] S2 oxidation precipitation: introducing ozone into the low-valent manganese iron leaching solution, oxidizing at 70°C to 80°C for 60min to 90min, adjusting the end point pH to 3.0 to 5.0, and filtering to obtain a solid mixture containing manganese dioxide and ferric hydroxide;

[0032] S3 calcination: the solid mixture containing manganese dioxide and iron hydroxide is mixed with solid sodium hydroxide, and calcined at 550° C. to 600° C. for 1 h to 2 h to obtain a thallium removal agent.

[0033] The method for preparing a thallium removal agent using zinc anode mud provided in an embodiment of the present invention has the following beneficial effects:

[0034] 1. The manganese element in the zinc anode mud is gradually extracted and converted into high-valent manganate by using the processes of reduction leaching, oxidation precipitation and calcination of zinc anode mud, thus realizing the resource utilization and harmless utilization of manganese element in zinc anode mud. 2. Zinc sulfide concentrate and / or ferrous sulfide are added to the zinc anode mud during reduction leaching. On the premise of not introducing impurities harmful to zinc smelting, on the one hand, high-valent manganese is reduced and extracted, and on the other hand, the iron element in the zinc sulfide concentrate or ferrous sulfide can be fully utilized. In the process of manganese extraction and conversion, iron is simultaneously converted into ferrite. The final thallium removal agent product contains highly oxidizing permanganate and easily hydrolyzed ferrite with adsorption. The thallium removal mechanism of the thallium removal agent is the principle of oxidation adsorption. 3. The raw materials used are easy to obtain, 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 three wastes are generated in the process. The obtained thallium removal agent product can be used for the thallium removal process of zinc smelting wastewater, which has obvious economic and environmental benefits.

[0035] In the technical solution of the embodiment of the present invention, the manganese element in the zinc electrolysis anode mud and the iron element in the zinc sulfide concentrate and / or ferrous sulfide are respectively utilized, and a thallium removal agent with strong oxidizing and adsorbing properties is obtained through reduction, oxidation and calcination. The process is simple and the thallium removal effect is good after application. The main chemical reactions occurring in the process include:

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

[0037] Fe2O3+6NaOH=Na3[Fe(OH)6]

[0038] In some embodiments, the reduction leaching further comprises:

[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 electrolysis waste liquid.

[0040] It is understandable that zinc anode mud is generally flaky and has a relatively hard texture. In order to speed up its reaction with dilute sulfuric acid and allow the effective components to react fully, it needs to be ball-milled to -200 mesh to account for more than 80%.

[0041] In some embodiments, the reduction leaching further comprises:

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

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

[0044] The concentration of dilute sulfuric acid is selected to be 160g / L to 200g / L mainly to match the concentration of zinc electrolysis waste liquid, so that zinc electrolysis waste liquid containing 160g / L to 200g / L of acid can be directly used to replace dilute sulfuric acid, reducing the amount of sulfuric acid used. It is understandable that sulfuric acid with lower or higher concentrations can also be used, but the amount of sulfuric acid used and the preparation process must be increased, and zinc electrolysis waste liquid cannot be directly used instead, which increases the cost investment.

[0045] In some embodiments, the reduction leaching further comprises:

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

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

[0048] In some embodiments, in the oxidation precipitation, sodium hydroxide and / or sodium carbonate are used to adjust the end point pH to 3.0-5.0.

[0049] Specifically, after the oxidation treatment is completed, the high-valent manganese ions are precipitated in the form of manganese dioxide, and the end point pH value of the solution needs to be adjusted to 3.0-5.0. Within this pH value range, the high-valent iron ions are hydrolyzed to form iron hydroxide precipitates.

[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 zinc anode mud. Our experiment summarizes the optimal parameters of S1 reduction leaching as follows: 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 70°C for 4h, the acid concentration at the end of the reaction is 30g / L, the liquid-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 that affect the effect of thallium removal are the preparation process of the solid mixture containing manganese dioxide and ferric hydroxide in the S2 oxidation precipitation and the step S3 calcination process, so below, we focus on optimizing the process parameters of S2 oxidation precipitation and S3 calcination.

[0051] Preferably, the oxidative precipitation is carried out by introducing ozone into the low-valent manganese iron leaching solution, performing oxidation treatment at 70°C to 72°C for 80min to 90min, adjusting the end point pH to 4.5 to 5.0, and filtering to obtain the solid mixture containing manganese dioxide and ferric hydroxide.

[0052] In this technical solution, ozone is a strong oxidant that can oxidize low-valent manganese ions 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 selected between 70°C and 80°C because ozone is a gas, and its solubility in water decreases with increasing temperature. When the temperature is below 70°C, 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 fewer effective components are finally formed; when the temperature is above 80°C, although the reaction rate of ozone with metal ions increases, its solubility in water is very low, and the reduction in effective concentration affects the reaction efficiency, which is not conducive to the oxidation process; taking all factors into consideration, the preferred temperature is 70°C to 72°C. The oxidation treatment time of the solution is 60min to 90min. If the reaction time is less than 60min, the low-valent manganese and iron ions cannot fully react, resulting in a low content of effective components in the oxidation precipitation product, affecting the effect of the thallium removal agent; if the reaction time is higher than 90min, the low-valent manganese and iron ions have been completely converted into high-valent states, and continuing to introduce ozone reaction will lead to ozone waste and increase the preparation cost; considering all factors, the preferred oxidation treatment time is 80min to 90min. After the oxidation treatment is completed, the high-valent manganese ions are precipitated in the form of manganese dioxide. The endpoint pH value of the solution needs to be adjusted so that the high-valent iron ions are hydrolyzed to form iron hydroxide precipitation. The preferred endpoint pH is 4.5 to 5.0. Through the coordinated 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 parameter conditions of S2 oxidation precipitation on the thallium removal rate of the thallium removal agent. The leaching conditions for S1 are that 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°C for 4h, and the acid concentration is 30g / L at the end of the reaction. The calcination conditions for S3 are all calcined at 600°C for 1.5h. As can be seen from Table 1, when the oxidation precipitation temperature is in the range of 70 to 85°C, as the temperature rises, the thallium removal rate decreases, when the temperature is 70°C, the thallium removal rate reaches 92.58%, and when the temperature is 65°C, the thallium removal rate reaches 89.64%; when the oxidation precipitation time is in the range of 50 to 90min, as time extends, the thallium removal rate increases, when the temperature is 80min, the thallium removal rate reaches 92.58%, when the time is further extended to 90min, the thallium removal rate increases less, and when the time is further extended to 100min, the thallium removal rate no longer increases; in the oxidation precipitation pH=2.0 to 6.0 range, as the pH increases, the thallium removal rate increases, when pH=5.0, the thallium removal rate reaches 92.58%, but when the pH is 6, the zinc hydrolysis precipitation will cause losses, so the pH is 3 to 5, preferably pH=4.5 to 5. Therefore, the optimal conditions for oxidation precipitation are temperature 70°C, time 80 min, and pH = 5.0.

[0053] Table 1 Effect of different temperatures, times and pH values ​​on the thallium removal rate of the obtained thallium removal agent during oxidation precipitation treatment (the dosage of the thallium removal agent used to remove thallium from thallium-containing solution is 3g / L)

[0054] Temperature ℃ Time min pH 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 to mix the solid mixture containing manganese dioxide and ferric hydroxide with solid sodium hydroxide, and calcine at 580° C. to 600° C. for 1.5 h to 2 h to obtain the thallium removal agent.

[0056] In this technical solution, a solid mixture containing manganese dioxide and iron hydroxide obtained by oxidation precipitation of S2 is mixed with solid sodium hydroxide, and calcined at 550℃~600℃ for 1h~2h to obtain a thallium remover. Among them, when the calcination temperature is lower than 550℃, the content of effective components formed by manganese dioxide, iron hydroxide and sodium hydroxide is low, which affects the use effect of the thallium remover; when the calcination temperature is higher than 600℃, the energy required for the reaction between manganese dioxide, iron hydroxide and sodium hydroxide can be met. Continuing to increase the temperature will cause energy waste, and high temperature may cause the effective components to decompose again, affecting the use effect of the thallium remover. When the calcination time is lower than 1h, the reaction between manganese dioxide, iron hydroxide and sodium hydroxide is insufficient, and the content of effective components is insufficient; when the calcination time is higher than 2h, the reaction between manganese dioxide, iron hydroxide and sodium hydroxide is complete. Continuing to extend the calcination time will lead to energy waste, and the effect of increasing the content of effective components is very small. For details, please see our optimization of the process parameters of the S3 calcination process, as shown in Table 2. Table 2 examines the effects of different parameters of the S3 calcination process on the thallium removal rate of the thallium removal agent. The conditions for S1 leaching are all 5:1 liquid-to-solid ratio of zinc anode mud to dilute sulfuric acid and / or zinc electrolysis waste liquid, 1.2 times the theoretical molar amount of zinc sulfide concentrate or ferrous sulfide added, reacting at 70°C for 4h, and the acid concentration at the end of the reaction is 30g / L. The conditions for S2 oxidation precipitation are all oxidation treatment at 70°C for 80min, and the end point pH is adjusted to 5.0. As can be seen from Table 2, within the range of calcination temperature of 530-620°C, with the increase of calcination temperature, the thallium removal rate shows an upward trend. After the temperature is 580°C, the rising trend of the thallium removal rate slows down. When the temperature is 600°C, the thallium removal rate is 92.58%; within the range of calcination time of 0.5-2.5h, with the extension of calcination time, the thallium removal rate shows an upward trend. After the time is 1.5°C, the rising trend of the thallium removal rate slows down. When the time is 1.5h, the thallium removal rate is 92.58%. Therefore, the optimal conditions for calcination treatment are temperature 600°C and time 1.5h.

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

[0058]

[0059]

[0060] According to a second aspect of the embodiments of the present invention, a thallium removing agent is provided, which is prepared by the above-mentioned method for preparing the thallium removing agent by using zinc anode mud.

[0061] Specifically, the thallium removal method of the thallium removal agent comprises: adding the thallium removal agent to a thallium-containing solution, adjusting the pH of the thallium-containing solution to not less than 3.0, the amount of the thallium removal agent is 4g / L to 6g / L, and the thallium removal reaction time is not less than 30min. Moreover, when the amount of the thallium removal agent is 5g / L, the thallium removal rate reaches more than 97%.

[0062] Specifically, the thallium removal agent prepared in the present application is suitable for thallium-containing solutions with a pH value not less than 3.0, and there is no requirement for the upper limit of the pH value. For zinc smelting thallium-containing solutions or wastewater, the pH value can generally be controlled at about 5.

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

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

[0065] S1 reduction leaching: After ball milling, the zinc electrolysis anode mud has a particle size of -200 mesh accounting for 80%, and is mixed with 160g / L dilute sulfuric acid at a liquid-solid ratio of 5:1. Manganese and iron are added to reduce the theoretical molar amount of 1.2 times the zinc sulfide concentrate or ferrous sulfide. The reaction is carried out at a temperature of 70°C for 4 hours, and the final acid is 30g / L. The low-valent manganese iron leaching solution is obtained by filtration, and the leaching residue is sent to the volatilization kiln for treatment.

[0066] S2 oxidation precipitation: ozone oxidation is introduced into the low-valent manganese iron leaching solution obtained in S1 at a temperature of 70°C for 80 minutes, and the end point pH is adjusted to 5 with sodium hydroxide or sodium carbonate. A solid mixture containing manganese dioxide and ferric hydroxide is obtained by filtration, and the filtrate is sent to zinc roasted sand for leaching.

[0067] S3 calcination, the solid mixture containing manganese dioxide and iron hydroxide obtained in S2 is mixed with solid sodium hydroxide, calcined at 600° C. for 1.5 hours, and then ground to obtain a 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 the present application is generally suitable for solutions or wastewaters with a pH value of more than 3.0. For solutions or wastewaters whose pH value does not meet the requirements, the pH value can be adjusted to the specified range, and the thallium removal agent is directly added to the solution or wastewater to be treated. Cadmium-depleted solution is a solution obtained after leaching and zinc powder replacement of cadmium slag from zinc smelting. It contains thallium up to 150-200 mg / L and is a representative high-thallium solution. As can be seen from Table 3 and Table 4, the self-prepared solution is an aqueous solution prepared by simulating the thallium content of the cadmium-depleted solution with thallium sulfate standard solution. Under the conditions of pH=4.5 and reaction time of 30min, the thallium removal rate increases with the increase of the amount of thallium removal agent. When the amount of thallium removal agent is 5g / L, the thallium removal rate reaches 97.45%; for the actual solution (cadmium-depleted solution), also under the conditions of pH=4.5 and reaction time of 30min, the thallium removal rate increases with the increase of the amount of thallium removal agent. When the amount of thallium removal agent is 5g / L, the thallium removal rate reaches 98.77%; in order to obtain a better thallium removal effect, the amount of thallium removal agent used is preferably in the range of 4-6g / L.

[0069] Table 3 Thallium removal effect of the thallium removal agent prepared in Example 1 for self-prepared thallium-containing solution

[0070]

[0071] Table 4 Thallium removal effect of the thallium removal agent prepared in Example 1 for use in production solution (cadmium-poor solution)

[0072]

[0073] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed. The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application. The above are only preferred implementation methods of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A method for preparing a thallium removal agent using zinc anode mud, characterized in that: include: Reduction leaching: 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 60℃~80℃ for 3h~5h, the acid concentration is 20g / L~30g / L at the end of the reaction, filter to obtain the leaching solution of low-valent manganese iron; Oxidation precipitation: introducing ozone into the low-valent ferromanganese leaching solution, oxidizing at 70° C. to 80° C. for 60 min to 90 min, adjusting the end point pH to 3.0 to 5.0, and filtering to obtain a solid mixture containing manganese dioxide and ferric hydroxide; Calcination: The solid mixture containing manganese dioxide and ferric hydroxide is mixed with solid sodium hydroxide, and calcined at 550° C. to 600° C. for 1 h to 2 h to obtain a thallium removal agent.

2. The method for preparing a thallium removal agent using zinc anode mud according to claim 1, characterized in that: The reduction leaching further comprises: 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 electrolysis waste liquid.

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

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

5. The method for preparing thallium removal agent by using zinc anode mud according to claim 1, characterized in that: In the oxidation precipitation, sodium hydroxide and / or sodium carbonate are used to adjust the end point pH to 3.0-5.

0.

6. The method for preparing thallium removal agent by using zinc anode mud according to claim 5, characterized in that: The oxidation precipitation is to introduce ozone into the low-valent ferromanganese leaching solution, perform oxidation treatment at 70°C to 72°C for 80min to 90min, adjust the end point pH to 4.5 to 5.0, and filter to obtain the solid mixture containing manganese dioxide and ferric hydroxide.

7. The method for preparing thallium removal agent by using zinc anode mud according to claim 1, characterized in that: The calcination is to mix the solid mixture containing manganese dioxide and iron hydroxide with solid sodium hydroxide, and calcine at 580° C. to 600° C. for 1.5 h to 2 h to obtain the thallium removing agent.

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

9. The thallium removing agent according to claim 8, characterized in that: The thallium removal method of the thallium removal agent comprises: The thallium removal agent is added to the thallium-containing solution, and the pH of the thallium-containing solution is adjusted to be not less 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 minutes.

10. The thallium removing 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 more than 97%.

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