A method for separating and producing manganese compounds and silver from a sulfur-containing manganese silver ore

Abstract

This application relates to the field of manganese-silver ore metallurgy technology, specifically to a method for separating and producing manganese compounds and silver from sulfur-bearing manganese-silver ore. The sulfur-bearing manganese-silver ore processed in this method contains 0.03wt%–0.3wt% Ag, 1.0wt%–3.0wt% Pb, 1.0wt%–3.0wt% Zn, 15wt%–35wt% S, 10wt%–25wt% Fe, and 15wt%–35wt% Mn. The sulfur-bearing manganese-silver ore is ball-milled and then oxidized under aeration at a relative humidity of 80–100% until it turns grayish-white. Sulfuric acid is added to the pretreated sulfur-bearing manganese-silver ore for mixed leaching and pressure filtration to obtain a manganese sulfate solution and a demanganese residue. The silver recovery rate in the demanganese residue is not less than 98%, and the manganese recovery rate in the manganese sulfate solution is not less than 92%. This method can not only comprehensively recover manganese and silver and improve the recovery rate of manganese and silver, but also greatly reduce the generation of hydrogen sulfide gas during the leaching process, which is conducive to the industrial promotion and application.

Description

Technical Field

[0001] This invention relates to the field of manganese silver ore metallurgy technology, specifically to a method for separating and producing manganese compounds and silver from sulfur-containing manganese silver ore. Background Technology

[0002] With the advancement of beneficiation and smelting technologies in recent years, manganese-silver ore has gradually been developed and utilized from its past status as a "dormant mine." Traditional oxidized manganese-silver ores have low sulfur content. When processing low-sulfur manganese-silver ores, the first step is to reduce and leach the manganese oxides. Using pyrite as a reducing agent to reduce tetravalent manganese to divalent manganese is the most commonly used method in industry. For example, Chinese patent CN111286603A discloses a method for leaching manganese using pyrite to obtain silver-containing leaching residue, followed by cyanide leaching to extract silver.

[0003] For manganese-silver ores with high sulfur content, the industry often uses them as the main source for silver extraction. This type of ore has high yield and low manganese valuation, so using it only for silver extraction results in a large waste of manganese and environmental pollution. However, conventional hydrometallurgical and pyrometallurgical processes are not suitable for manganese-silver ores with high sulfur content: In commonly used hydrometallurgical extraction techniques for manganese and silver, sulfuric acid leaching is often used. Directly leaching this high-sulfur manganese-silver ore with sulfuric acid will produce a large amount of hydrogen sulfide gas. Even with the addition of an alkaline spraying device, hydrogen sulfide will still overflow, threatening the health and lives of workers and causing environmental pollution. When processing high-sulfur manganese-silver ore using pyrometallurgical methods, the high manganese content can easily cause furnace caking due to manganese oxides and the low-melting-point eutectics formed with other components. Even if the manganese content is reduced to a suitable level for furnace feeding using ore blending methods, manganese resources are still wasted.

[0004] Therefore, in order to make fuller use of high-sulfur manganese-silver ores with high yield and low cost, it is necessary to develop a manganese-silver separation method that has good separation efficiency and does not produce environmental pollution or safety hazards. Summary of the Invention

[0005] To address the problems of existing technologies, this invention proposes a method for separating and producing manganese compounds and silver from sulfur-containing manganese-silver ore, comprising the following steps:

[0006] A method for separating and producing manganese compounds and silver from sulfur-containing manganese-silver ore, characterized by comprising the following steps:

[0007] Step 1: The sulfur-containing manganese silver ore contains 0.03wt% to 0.3wt% Ag, 1.0wt% to 3.0wt% Pb, 1.0wt% to 3.0wt% Zn, 15wt% to 35wt% S, 10wt% to 25wt% Fe, and 15wt% to 35wt% Mn. The sulfur-containing manganese silver ore is crushed and ball-milled, and then oxidized by ventilation for 10 to 60 days under conditions of relative humidity of 80 to 100% and temperature of 20 to 40°C until the surface of the sulfur-containing manganese silver ore changes from black to grayish-white. Then the pile is turned over, and the turning operation is repeated 2 to 5 times to obtain pretreated sulfur-containing manganese silver ore.

[0008] Step 2: First, add water or sulfuric acid-containing waste liquid from the production process to the reactor. Then, slowly add concentrated sulfuric acid and pretreated sulfur-containing manganese-silver ore. Control the reaction system temperature at 40-60℃ during feeding. The ratio of sulfuric acid content to pretreated sulfur-containing manganese-silver ore in the reactor should be 0.6-0.8:1. The total liquid-to-solid ratio in the reaction system should be 2-8:1. After feeding, raise the temperature to 80-95℃ and leach for 2-3 hours. Maintain the pH value at 1.5-2.0 during the reaction. Keep the pressure inside the reactor at -0.05MPa to -0.1MPa throughout the reaction. Then, filter while hot to obtain manganese sulfate solution and demanganese residue. The silver recovery rate in the demanganese residue should be no less than 98%, and the silver grade in the demanganese residue should be 0.04wt%-4.5wt%, which is more than 1.4 times that of the original ore. The manganese recovery rate in the manganese sulfate solution should be no less than 92%.

[0009] Step 3: The demanganese residue obtained in Step 2 is used to extract silver using a wet process; the manganese sulfate solution is purified to obtain a purified manganese sulfate solution, which is then further crystallized to produce manganese sulfate crystals or electrolyzed to produce electrolytic manganese dioxide.

[0010] Furthermore, the sulfur-bearing manganese silver ore contains 0.05wt%~0.2wt% Ag, 1.8wt%~3.0wt% Pb, 1.8wt%~3.0wt% Zn, 20wt%~35wt% S, 10wt%~25wt% Fe, and 15wt%~35wt% Mn.

[0011] Further, in step 1, the sulfur-containing manganese silver ore is crushed and ball-milled to a particle size of 200-300 mesh or more than 60%.

[0012] Furthermore, during the ventilation oxidation process described in step 1, the pile is turned over every 2 to 10 days.

[0013] Furthermore, the gas generated in the leaching reaction described in step 2 enters the alkaline absorption tower.

[0014] Furthermore, the pretreated sulfur-containing manganese-silver ore added to the reactor in step 2 is a sulfur-containing manganese-silver ore slurry with added water or sulfuric acid, wherein the sulfuric acid slurry is carried out in a rotary kiln.

[0015] Furthermore, the concentrated sulfuric acid in step 2 is added in two stages: first, water or sulfuric acid-containing waste liquid from the production process is added to the reactor to submerge the first stirring blade at the bottom of the reactor; then, concentrated sulfuric acid is added for the first time, the amount of which is 50% to 80% of the total amount of sulfuric acid; then, the pretreated sulfur-containing manganese-silver ore obtained in step 1 is added; after the pretreated sulfur-containing manganese-silver ore has been fed into the reaction system, concentrated sulfuric acid or water / sulfuric acid-containing waste liquid is added to the reaction system.

[0016] Furthermore, the concentration of the concentrated sulfuric acid mentioned in step 2 is above 97%, and the replenishment rate is 1 to 2 tons / hour.

[0017] Further, in step 3, the demanganese slag is used to extract silver using a wet process: a silver leaching agent with hydrochloric acid medium is added to the demanganese slag for leaching and dissolution, and after pressure filtration, Fe powder is added to the filtrate for displacement to obtain crude silver. Sodium chlorate and sulfuric acid are added to the crude silver for impurity removal, and after pressure filtration, impurity-removed slag is obtained. Ammonia water is added to the impurity-removed slag first, and then hydrazine hydrate is added to reduce it to obtain refined silver. After pressure filtration, drying, and casting, silver ingots are obtained.

[0018] Furthermore, the H in the silver impregnation agent of the hydrochloric acid medium + The concentration is 7.5 mol / L, Fe 3+ The concentration is 60 g / L, Fe 2+ The concentration is 15 g / L, and the leaching and dissolution temperature is 103~108℃.

[0019] Further, the manganese sulfate solution purification process in step 3 is as follows: first, MnO2 is added, then the solution is heated to 85~95℃, the pH value is adjusted to 2.5~3.0, then quicklime and barium sulfide are added, the pH value of the solution is adjusted to 5~6, then the solution is filtered to obtain the iron-removed liquid, and then a sulfiding agent is slowly added to the iron-removed liquid, and the purified manganese sulfate solution is obtained after filtration.

[0020] In the raw ore, tiny Ag 0 Silver sulfides are usually tightly wrapped and coexisting with major sulfide minerals such as pyrite (FeS2), ZnS, and PbS. When acid is added directly for leaching, it is difficult for the acid to effectively penetrate into the mineral and come into contact with the silver. When an oxidant is added directly, elemental sulfur is easily generated on the mineral surface, which passivates the surface and makes it difficult for the silver to be exposed. Therefore, the silver recovery rate is difficult to improve by referring to existing technologies, whether it is direct acid leaching or acid leaching after adding an oxidant. In addition, a large amount of hydrogen sulfide gas is easily generated during the acid leaching process.

[0021] The method of this invention first subjectes the crushed raw ore to natural weathering and oxidation. On one hand, natural weathering breaks down the sulfide minerals encapsulating the silver, oxidizing FeS2 and MnS to form porous, loose iron / manganese oxides / hydroxides, and oxidizing ZnS to form soluble ZnSO4. This loosens the minerals surrounding the silver particles, exposing the silver and making it easier for it to come into contact with the leaching agent, sulfuric acid. On the other hand, in the acidic environment generated during the weathering process (from H2SO4 produced by sulfur oxidation), the silver can partially dissolve into Ag. + Ion: Ag 0 +Fe 3+ →Ag + +Fe 2+ soluble Ag + After migrating a short distance in solution, ions can easily become toxic if they encounter any reducing agent (such as residual sulfides, Fe). 2+ Ions, and even organic matter, will be reduced back to metallic silver: Ag + +Fe 2+ →Ag 0 +Fe 3+ Silver ions migrate and recrystallize as Ag in more favorable locations (such as pores and cracks). 0 The repeated dissolution-reprecipitation process causes the tiny silver particles to gradually grow larger and purer (Ostwald Ripening phenomenon), and after weathering and aggregation, Ag is formed. 0 It is not easily dissolved in dilute sulfuric acid, and can be recovered to the maximum extent in the demanganese residue.

[0022] At the same time, the original ore contains a large amount of S 2- When sulfuric acid is added, a large amount of hydrogen sulfide is produced. This invention utilizes the weathering process to oxidize FeS2: 2FeS2 + 7O2 + 2H2O → 2FeSO4 + 2H2SO4. The generated sulfuric acid (H2SO4) acidifies the mining environment, greatly promoting the dissolution and oxidation of other sulfides. The generated ferrous sulfate (FeSO4) is further oxidized and hydrolyzed: 4FeSO4 + O2 + 2H2SO4 → 2Fe2(SO4)3 + 2H2O. 3+ It is a very important oxidizing agent, capable of directly oxidizing other sulfides, forming an autocatalytic cycle that continuously accelerates the reaction. At this point, the manganese ore is also reacted with O2 and Fe. 3+ Oxidation occurs, producing soluble sulfate. Therefore, the sulfide source that could produce H₂S is oxidized to the higher oxidation state sulfate ion, SO₄²⁻. 2- Since sulfates react with acids to produce no more H2S, adding sulfuric acid will not produce hydrogen sulfide gas or will only produce trace amounts of hydrogen sulfide.

[0023] This method is simple and low-cost, and can efficiently recover and separate silver and manganese from high-sulfur manganese silver ore without the need for additional oxidants. Furthermore, it greatly reduces the amount of hydrogen sulfide gas generated during acid leaching, which is beneficial for industrial application and promotion. Attached Figure Description

[0024] Figure 1 A process flow diagram of the present invention is shown. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is further described in detail below through specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0026] Reference Flow Chart of the Invention Figure 1 .

[0027] Example 1

[0028] A method for separating and producing manganese compounds and silver from sulfur-containing manganese-silver ore includes the following steps:

[0029] Step 1: The sulfur-containing manganese-silver ore contains Ag 0.0751wt%, Pb 2.51wt%, Zn 2.2wt%, S 28.5wt%, Fe 22.09wt%, Mn 31.5wt%, with the balance being other impurity elements. The sulfur-containing manganese-silver ore is crushed and ball-milled to a particle size of 200 mesh or more than 60%. Then, it is oxidized in a ventilated environment for 30 days under conditions of relative humidity of 80-100% and temperature of 20-28℃, with turning over every 7 days, until the sulfur-containing manganese-silver ore changes from black to grayish-white, thus obtaining the pretreated sulfur-containing manganese-silver ore.

[0030] Step 2: First add 25m to the reaction vessel 3 The waste liquid generated from the electrolytic production of manganese dioxide (specifically, the waste liquid generated from the electrolytic production of manganese sulfate) is then treated by adding 2 tons of 98% concentrated sulfuric acid at a rate of 0.2 tons / minute. Next, 8 tons of pretreated sulfur-containing manganese-silver ore obtained in step 1 are added. After the initial feeding, another 1 ton of 98% sulfuric acid is added at a rate of 1 ton / hour. Following the addition of sulfuric acid, the waste liquid from the electrolytic production of manganese dioxide is then added until the volume reaches 60 m³. 3The waste liquid contained approximately 2.5 tons of waste acid (sulfuric acid). The temperature during feeding was 45℃, and the pressure during both feeding and reaction was -0.05 to -0.1 MPa. The reaction was carried out in a semi-closed reactor, maintaining a slightly negative pressure to prevent the possible escape of hydrogen sulfide gas. After feeding, the temperature was raised to approximately 90℃ and maintained for another 2 hours of leaching. The pH value was maintained at 1.6 to 1.8 during the reaction, adjusted by adding pretreated sulfur-containing manganese-silver ore or concentrated sulfuric acid. Subsequently, the manganese sulfate solution and demanganese residue were obtained by hot pressure filtration. The silver recovery rate in the demanganese residue was 98.50%, the silver grade in the demanganese residue was 0.1273 wt%, and the manganese recovery rate in the manganese sulfate solution was 93.16%. Almost no hydrogen sulfide gas was generated during the leaching process. The liquid-solid mass ratio of the sodium hydroxide solution added to the alkaline absorption tower to the manganese-silver ore was 0.01:1, and the hydrogen sulfide gas detector showed 0~10 PPM.

[0031] Step 3: Add a hydrochloric acid-medium silver leaching agent to the demanganese residue produced in Step 2 for high-temperature leaching and dissolution. The hydrochloric acid-medium silver leaching agent contains H... + The concentration is 7.5 mol / L, Fe 3+ The concentration is 60 g / L, Fe 2+ The concentration was 15 g / L, the leaching reaction temperature was 105℃, and the silver-containing solution was obtained by pressure filtration. Fe powder was added to the silver-containing solution for reduction and replacement. The amount of Fe powder added was 1.2 times the theoretical amount. The iron powder reduction temperature was 80℃. The crude silver powder was obtained by pressure filtration. Sodium chlorate and dilute sulfuric acid were added to the crude silver powder for impurity removal. After pressure filtration, the residue after impurity removal was obtained. Ammonia water was added to the residue first, and after pressure filtration, hydrazine hydrate was added for reduction. After pressure filtration, refined silver powder was obtained. The refined silver powder was dried and cast to obtain silver ingots.

[0032] The impurity removal process of manganese sulfate solution is as follows: First, add iron-removing MnO2 powder, then heat the solution to about 90°C, adjust the pH value to 2.5~3.0, add quicklime and barium sulfide, adjust the pH value of the solution to 5~6, then filter to obtain the iron-removed liquid, and then slowly add sulfiding agent to the iron-removed liquid. After filtration, a qualified purified manganese sulfate solution is obtained for crystallization to produce manganese sulfate crystals, or for further production of electrolytic manganese dioxide.

[0033] Example 2

[0034] A method for separating and producing manganese compounds and silver from sulfur-containing manganese-silver ore includes the following steps:

[0035] Step 1: The sulfur-containing manganese-silver ore contains Ag 0.0723wt%, Pb 1.21wt%, Zn 1.3wt%, S 23.55wt%, Fe 15.9wt%, and Mn 20.3wt%. The sulfur-containing manganese-silver ore is crushed and ball-milled to a particle size of 200 mesh or more than 60%. Then, it is oxidized in a ventilated environment for 20 days under conditions of relative humidity of 90-100% and temperature of 30-38℃, with turning over every 10 days, until the sulfur-containing manganese-silver ore changes from black to grayish-white, thus obtaining the pretreated sulfur-containing manganese-silver ore.

[0036] Step 2: First, simultaneously and evenly add sulfuric acid-containing waste liquid generated during the production process, 5 tons of 98% concentrated sulfuric acid, and 12 tons of pretreated sulfur-containing manganese-silver ore to the rotary kiln to obtain a sulfur-containing manganese-silver ore slurry. The feeding time is 4 hours, and the temperature of the rotary kiln is 60℃. The slurry is then transported to a semi-enclosed reactor, with a total liquid volume of 60m³ in the reactor. 3 The temperature was 50℃, and the waste liquid contained approximately 2.5 tons of waste acid (sulfuric acid). The pressure was -0.05 to -0.1 MPa. The reaction system was maintained at a slightly negative pressure to prevent the possible leakage of hydrogen sulfide gas. After all the slurry was fed into the reactor, the temperature was raised to about 90℃ and maintained at this temperature for another 3 hours. During the reaction, the pH value was maintained at 1.8 to 2.0, and the pH value was adjusted by adding ore or sulfuric acid. Subsequently, the manganese sulfate solution and manganese removal slag were obtained by hot pressure filtration. The silver recovery rate in the manganese removal slag was 98.20%, and the silver grade in the manganese removal slag was 0.1032 wt%. The manganese recovery rate in the manganese sulfate solution was 92.16%. Almost no hydrogen sulfide gas was generated during the leaching process. The liquid-solid mass ratio of sodium hydroxide solution added to the alkaline absorption tower to manganese-silver ore was 0.01:1, and the hydrogen sulfide gas detector showed 0 to 10 PPM.

[0037] Step 3: The purification process for silver and manganese is the same as in Example 1.

[0038] Example 3

[0039] A method for separating and producing manganese compounds and silver from sulfur-containing manganese-silver ore includes the following steps:

[0040] Step 1: The sulfur-bearing manganese-silver ore contains Ag 0.0522wt%, Pb 1.05wt%, Zn 1.23wt%, S 25.8wt%, Fe 18.56wt%, and Mn 18.01wt%. The sulfur-bearing manganese-silver ore is crushed and ball-milled to a particle size of 300 mesh or more than 60%. Then, it is oxidized in a ventilated environment for 20 days under conditions of relative humidity of 90-100% and temperature of 30-38℃, with turning every 7 days, until the sulfur-bearing manganese-silver ore changes from black to grayish-white, thus obtaining the pretreated sulfur-bearing manganese-silver ore.

[0041] Step 2: First, add 30m to the reaction vessel. 3Water was added, followed by 7 tons of 98% concentrated sulfuric acid at a rate of 0.3 tons / minute. Then, 15 tons of pretreated sulfur-containing manganese-silver ore were added. After the initial addition, 3 tons of 98% sulfuric acid were added at a rate of 2 tons / hour. After the sulfuric acid was added, water was added until the solution reached 60 m³. 3 The feeding process was carried out at a temperature of 60℃, with a pressure of -0.05 to -0.1 MPa during both feeding and reaction. The reaction was conducted in a semi-closed reactor, maintaining a slightly negative pressure to prevent the possible escape of hydrogen sulfide gas. After feeding, the temperature was raised to approximately 95℃ and maintained for another 3 hours, with the pH value maintained between 1.7 and 1.9. Subsequently, the mixture was separated by hot pressure filtration to obtain a manganese sulfate solution and a demanganese residue. The silver recovery rate in the demanganese residue was 98.36%, with a silver grade of 0.0758 wt%, while the manganese recovery rate in the manganese sulfate solution was 92.02%. Almost no hydrogen sulfide gas was generated during the leaching process. The liquid-to-solid mass ratio of the sodium hydroxide solution added to the alkaline absorption tower to the manganese-silver ore was 0.01:1, and the hydrogen sulfide gas detector showed a reading of 0–10 PPM.

[0042] Step 3: The purification process for silver and manganese is the same as in Example 1.

[0043] Comparative Example 1

[0044] A method for separating and producing manganese compounds and silver from sulfur-containing manganese-silver ore includes the following steps:

[0045] Step 1: The sulfur-containing manganese-silver ore contains Ag 0.0751wt%, Pb 2.51wt%, Zn 2.2wt%, S 28.5wt%, Fe 22.09wt%, and Mn 31.5wt%. The sulfur-containing manganese-silver ore is crushed and ball-milled to a particle size of 200 mesh or more than 60%. Then, it is oxidized for 60 days in a closed warehouse without ventilation under conditions of relative humidity of 80-100% and temperature of 20-28℃. The sulfur-containing manganese-silver ore is turned over every 7 days. The color of the sulfur-containing manganese-silver ore does not change significantly and it does not turn white. The pretreated sulfur-containing manganese-silver ore is obtained.

[0046] Step 2: (This step is the same as in Example 1) First, add 25m to the reaction vessel. 3 The waste liquid generated from the electrolytic production of manganese dioxide (specifically, the waste liquid generated from the electrolytic production of manganese sulfate) is then treated by adding 2 tons of 98% concentrated sulfuric acid at a rate of 0.2 tons / minute. Next, 8 tons of pretreated sulfur-containing manganese-silver ore obtained in step 1 are added. After the initial feeding, another 1 ton of 98% sulfuric acid is added at a rate of 1 ton / hour. Following the addition of sulfuric acid, the waste liquid from the electrolytic production of manganese dioxide is then added until the volume reaches 60 m³. 3The waste liquid contained approximately 2.5 tons of waste acid (sulfuric acid). The temperature during feeding was 45℃, and the pressure during both feeding and reaction was -0.05 to -0.1 MPa. The reaction was carried out in a semi-closed reactor, maintaining a slightly negative pressure to prevent the possible escape of hydrogen sulfide gas. After feeding, the temperature was raised to approximately 90℃ and maintained for another 2 hours of leaching. The pH value was maintained at 1.6 to 1.8 during the reaction, adjusted by adding pretreated sulfur-containing manganese-silver ore or concentrated sulfuric acid. Subsequently, the manganese sulfate solution and demanganese residue were obtained by hot pressure filtration. The silver recovery rate in the demanganese residue was 98.5%, the silver grade in the demanganese residue was 0.1223 wt%, and the manganese recovery rate in the manganese sulfate solution was 91.7%. Despite the addition of a large amount of alkali solution, a large amount of hydrogen sulfide gas was still generated during the leaching process. The ratio of sodium hydroxide solution of the same concentration as in Example 1 to manganese silver ore added to the alkali absorption tower was 0.04:1, and the hydrogen sulfide gas detector showed 50~200 PPM.

[0047] Step 3: The purification process for silver and manganese is the same as in Example 1.

[0048] Comparative Example 2

[0049] A method for separating and producing manganese compounds and silver from sulfur-containing manganese-silver ore includes the following steps:

[0050] Step 1: The sulfur-containing manganese-silver ore contains Ag 0.0751wt%, Pb 2.51wt%, Zn 2.2wt%, S 28.5wt%, Fe 22.09wt%, and Mn 31.5wt%. The sulfur-containing manganese-silver ore is crushed and ball-milled to a particle size of 200 mesh or more than 60%. Then, it is oxidized for 60 days in a closed warehouse without ventilation under conditions of relative humidity of 80-100% and temperature of 20-28℃. The sulfur-containing manganese-silver ore is turned over every 7 days and sprayed with 30% hydrogen peroxide once. The reaction is violent when spraying hydrogen peroxide, and the ore may be sprayed into the air, which is dangerous. The sulfur-containing manganese-silver ore turns slightly white, and the pretreated sulfur-containing manganese-silver ore is obtained.

[0051] Step 2: (This step is the same as in Example 1) First, add 25m to the reaction vessel. 3 The waste liquid generated from the electrolytic production of manganese dioxide (specifically, the waste liquid generated from the electrolytic production of manganese sulfate) is then treated by adding 2 tons of 98% concentrated sulfuric acid at a rate of 0.2 tons / minute. Next, 8 tons of pretreated sulfur-containing manganese-silver ore obtained in step 1 are added. After the initial feeding, another 1 ton of 98% sulfuric acid is added at a rate of 1 ton / hour. Following the addition of sulfuric acid, the waste liquid from the electrolytic production of manganese dioxide is then added until the volume reaches 60 m³. 3The waste liquid contained approximately 2.5 tons of waste acid (sulfuric acid). The temperature during feeding was 45℃, and the pressure during both feeding and reaction was -0.05 to -0.1 MPa. The reaction was carried out in a semi-closed reactor, maintaining a slightly negative pressure to prevent the possible escape of hydrogen sulfide gas. After feeding, the temperature was raised to approximately 90℃ and maintained for another 2 hours of leaching. The pH value was maintained at 1.6 to 1.8 during the reaction, adjusted by adding pretreated sulfur-containing manganese-silver ore or concentrated sulfuric acid. Subsequently, the manganese sulfate solution and demanganese residue were obtained by hot pressure filtration. The silver recovery rate in the demanganese residue was 98.1%, the silver grade in the demanganese residue was 0.1205 wt%, and the manganese recovery rate in the manganese sulfate solution was 92.1%. A small amount of hydrogen sulfide gas was still generated during the leaching process. The ratio of sodium hydroxide solution of the same concentration as in Example 1 to manganese silver ore added to the absorption tower was 0.04:1, and the hydrogen sulfide gas detector showed 10~100 PPM.

[0052] Step 3: The purification process for silver and manganese is the same as in Example 1.

[0053] Comparative Example 3

[0054] A method for separating and producing manganese compounds and silver from sulfur-containing manganese-silver ore includes the following steps:

[0055] Step 1: The sulfur-containing manganese-silver ore contains Ag 0.0751wt%, Pb 2.51wt%, Zn 2.2wt%, S 28.5wt%, Fe 22.09wt%, and Mn 31.5wt%. The sulfur-containing manganese-silver ore is crushed and ball-milled to a particle size of 200 mesh or less (more than 60%). Then, it is oxidized in a ventilated environment for 30 days under dry conditions (relative humidity below 30%) and a temperature of 20~28℃. The pile is turned over every ten days. The color of the sulfur-containing manganese-silver ore does not change significantly and remains black. The pretreated sulfur-containing manganese-silver ore is obtained.

[0056] Step 2: First add 25m to the reaction vessel 3 The waste liquid generated from the electrolytic production of manganese dioxide is then mixed with 3 tons of 98% concentrated sulfuric acid at a rate of 0.2 tons / minute, followed by 8 tons of pretreated sulfur-containing manganese-silver ore obtained in step 1. The waste liquid from the electrolytic production of manganese dioxide is then replenished to a final volume of 60 m³. 3The waste liquid contained approximately 2.5 tons of waste acid (sulfuric acid). The temperature during feeding was 50°C, and the pressure during feeding and reaction was -0.05 to -0.1 MPa. After feeding, the temperature was raised to approximately 90°C and maintained at this temperature for about 2 hours of leaching reaction. The pH value during the reaction was 2.8 to 3.0. Subsequently, manganese sulfate solution and demanganese residue were obtained by hot pressure filtration. The silver recovery rate in the demanganese residue was 97.5%, and the silver grade in the demanganese residue was 0.0998 wt%. The manganese recovery rate in the manganese sulfate solution was 83.1%. A large amount of hydrogen sulfide gas was generated during the leaching process. The ratio of sodium hydroxide solution of the same concentration as in Example 1 to manganese-silver ore added to the absorption tower was 0.06:1, and the hydrogen sulfide gas detector showed 200-500 PPM.

[0057] Step 3: The purification process for silver and manganese is the same as in Example 1.

[0058]

[0059]

[0060] As can be seen from Tables 1 and 2:

[0061] The pretreatment scheme of "ventilation + high humidity (80~100%)" of this invention can fully oxidize and fix the sulfides in the ore in the demanganese slag, turning the ore from black to white and reducing the generation of hydrogen sulfide in the leaching stage from the source. However, Comparative Example 1 (no ventilation) and Comparative Example 3 (dry ventilation) did not achieve effective oxidation, resulting in most of the sulfides reacting with sulfuric acid in the leaching stage to generate hydrogen sulfide gas that overflowed. Therefore, the sulfur content in the demanganese slag of Example 1 was higher than that of the comparative example. Moreover, the manganese recovery rate of Comparative Example 3 was significantly reduced due to the inhibition of oxidation reaction by the drying conditions.

[0062] Although Comparative Example 2 slightly whitened the ore by spraying hydrogen peroxide, it posed safety risks of violent reaction and mineral splashing. Furthermore, it still required several times more alkaline solution to absorb hydrogen sulfide than the present invention, and the silver recovery rate was slightly lower than that of the present invention, proving that the scheme was neither safe nor economical.

[0063] The pH value for ore leaching in this invention is limited to 1.6-1.8. At the same time, the leaching time, leaching temperature, leaching pressure, and sulfuric acid replenishment method are coordinated with the pretreatment process to minimize the amount of alkali solution used while ensuring a high recovery rate. In contrast, Comparative Example 3 has a higher pH value (2.8-3.0), resulting in insufficient manganese leaching, a significant decrease in recovery rate, and a surge in hydrogen sulfide generation. It requires several times more alkali solution than this invention, further verifying the rationality of the parameter design in this invention.

[0064] This invention achieves a triple benefit of high resource recovery rate (manganese ≥92%, silver ≥98%), low safety risk (virtually no hydrogen sulfide), and low cost (minimum alkali usage) through a "ventilation + high humidity" ore pretreatment process combined with precise leaching parameter control. In contrast, comparative examples 1-3, due to improper pretreatment processes or parameters, all suffer from low efficiency, high safety risk, high cost, or low recovery rate. In summary, this invention, through ventilated oxidation pretreatment under conditions of 80-100% relative humidity and 20-40℃, can efficiently recover and separate silver and manganese from high-sulfur manganese-silver ores without the need for additional oxidants. Furthermore, it significantly reduces the hydrogen sulfide gas generated during acid leaching, which is beneficial for industrial application and promotion.

[0065] The foregoing descriptions have outlined some exemplary embodiments of the present invention. It is understood that these embodiments are merely illustrative and do not constitute a limitation on the scope of protection of the present invention. Features in these embodiments can be rearranged in suitable ways, and the resulting solutions remain within the scope of protection claimed by the present invention. All other embodiments obtained by those skilled in the art based on the foregoing embodiments without inventive effort, i.e., all modifications, equivalent substitutions, and improvements made within the spirit and principles of this application, fall within the scope of protection claimed by the present invention.

Claims

1. A method for separating and producing manganese compounds and silver from sulfur-containing manganese-silver ore, characterized in that, Includes the following steps: Step 1: The sulfur-containing manganese-silver ore contains 0.03wt% to 0.3wt% Ag, 1.0wt% to 3.0wt% Pb, 1.0wt% to 3.0wt% Zn, 15wt% to 35wt% S, 10wt% to 25wt% Fe, and 10wt% to 35wt% Mn. The sulfur-containing manganese-silver ore is crushed and ball-milled, and then oxidized by ventilation for 10 to 60 days under conditions of relative humidity of 80 to 100% and temperature of 20 to 40°C until the surface of the sulfur-containing manganese-silver ore changes from black to grayish-white. Then the pile is turned over, and the turning operation is repeated 2 to 5 times to obtain pretreated sulfur-containing manganese-silver ore. Step 2: First, add water or sulfuric acid-containing waste liquid from the production process to the reactor. Then, slowly add concentrated sulfuric acid and pretreated sulfur-containing manganese-silver ore. Control the reaction system temperature at 40-60℃ during feeding. The ratio of sulfuric acid content to pretreated sulfur-containing manganese-silver ore in the reactor should be 0.6-0.8:

1. The total liquid-to-solid ratio in the reaction system should be 2-8:

1. After feeding, raise the temperature to 80-95℃ and leach for 2-3 hours. Maintain the pH value at 1.5-2.0 during the reaction. Keep the pressure inside the reactor at -0.05MPa to -0.1MPa throughout the reaction. Then, filter while hot to obtain manganese sulfate solution and demanganese residue. The silver recovery rate in the demanganese residue should be no less than 98%, and the silver grade in the demanganese residue should be 0.04wt%-4.5wt%, which is more than 1.4 times that of the original ore. The manganese recovery rate in the manganese sulfate solution should be no less than 92%. Step 3: The demanganese residue obtained in Step 2 is used to extract silver using a wet process; the manganese sulfate solution is purified to obtain a purified manganese sulfate solution, which is then further crystallized to produce manganese sulfate crystals or electrolyzed to produce electrolytic manganese dioxide.

2. The method for separating and producing manganese compounds and silver from sulfur-bearing manganese-silver ore according to claim 1, characterized in that, The sulfur-bearing manganese silver ore contains 0.05wt%~0.2wt% Ag, 1.8wt%~3.0wt% Pb, 1.8wt%~3.0wt% Zn, 20wt%~35wt% S, 10wt%~25wt% Fe, and 15wt%~35wt% Mn.

3. The method for separating and producing manganese compounds and silver from sulfur-bearing manganese-silver ore according to claim 1, characterized in that, In step 1, the sulfur-containing manganese silver ore is crushed and ball-milled to a particle size of 200-300 mesh or more (60% or more of the particles are 200-300 mesh).

4. The method for separating and producing manganese compounds and silver from sulfur-bearing manganese-silver ore according to claim 1, characterized in that, During the ventilation oxidation process described in step 1, the pile is turned over every 2 to 10 days.

5. The method for separating and producing manganese compounds and silver from sulfur-bearing manganese-silver ore according to claim 1, characterized in that, The gas generated in the leaching reaction described in step 2 enters the alkaline absorption tower.

6. The method for separating and producing manganese compounds and silver from sulfur-bearing manganese-silver ore according to claim 1, characterized in that, The pretreated sulfur-containing manganese-silver ore added to the reactor in step 2 is a sulfur-containing manganese-silver ore slurry that has been slurried with water or sulfuric acid, wherein the sulfuric acid slurry is carried out in a rotary kiln.

7. The method for separating and producing manganese compounds and silver from sulfur-containing manganese-silver ore according to claim 1, characterized in that, In step 2, the concentrated sulfuric acid is added in two stages: first, water or sulfuric acid-containing waste liquid from the production process is added to the reactor to submerge the first stirring blade at the bottom of the reactor; then, concentrated sulfuric acid is added for the first time, with the amount of concentrated sulfuric acid added being 50% to 80% of the total amount of sulfuric acid; then, the pretreated sulfur-containing manganese-silver ore obtained in step 1 is added; after the pretreated sulfur-containing manganese-silver ore has been fed into the reaction system, concentrated sulfuric acid or water / sulfuric acid-containing waste liquid is added to the reaction system.

8. A method for separating and producing manganese compounds and silver from sulfur-containing manganese-silver ore according to claim 7, characterized in that, In step 2, the concentration of concentrated sulfuric acid is above 97%, and the replenishment rate is 1 to 2 tons per hour.

9. A method for separating and producing manganese compounds and silver from sulfur-bearing manganese-silver ore according to claim 1, characterized in that, In step 3, the demanganese slag is used to extract silver using a wet process: a silver leaching agent with hydrochloric acid medium is added to the demanganese slag for leaching and dissolution, and after pressure filtration, Fe powder is added to the filtrate for displacement to obtain crude silver. Sodium chlorate and sulfuric acid are added to the crude silver for impurity removal, and after pressure filtration, impurity-removed slag is obtained. Ammonia water is added to the impurity-removed slag first, and then hydrazine hydrate is added to reduce it to obtain refined silver. After pressure filtration, drying, and casting, silver ingots are obtained.

10. A method for separating and producing manganese compounds and silver from sulfur-bearing manganese-silver ore according to claim 9, characterized in that, The silver immersion agent in the hydrochloric acid medium contains H + The concentration is 7.5 mol / L, Fe 3+ The concentration is 60 g / L, Fe 2+ The concentration is 15 g / L, and the leaching and dissolution temperature is 103~108℃.

11. A method for separating and producing manganese compounds and silver from sulfur-bearing manganese-silver ore according to claim 1, characterized in that, The impurity removal process of the manganese sulfate solution in step 3 is as follows: First, MnO2 is added, then the solution is heated to 85~95℃ and the pH value is adjusted to 2.5~3.

0. Then, quicklime and barium sulfide are added and the pH value of the solution is adjusted to 5~6. Then, the solution is filtered to obtain the iron-removed liquid. Then, a sulfiding agent is slowly added to the iron-removed liquid and filtered to obtain the purified manganese sulfate solution.

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