Method for recovering manganese and lead by reducing and leaching electrolytic manganese anode slag through alkali activated sulfur powder

Abstract

The invention discloses a method for recovering manganese and lead by reducing and leaching electrolytic manganese anode slag through alkali-activated sulfur powder, which comprises the following steps: S1, uniformly mixing the electrolytic manganese anode slag, the sulfur powder and solid alkali, and heating and activating to obtain an activated and reduced material; s2, the activation reduction material is leached with dilute sulfuric acid, and a manganese-containing leaching solution and lead sulfate-containing leaching residues are obtained after liquid-solid separation; and S3, the leaching residues are leached through a chlorine salt solution, and a lead-containing solution and the leaching residues are obtained after solid-liquid separation. The method is simple and easy to operate, the reducing agent is wide in source and low in cost, the leaching rate of manganese and lead can be effectively increased, and the concentration of impurities in the leachate is low; secondary waste residue pollution and waste gas pollution are not generated in the whole process, so that the pollution to the environment is effectively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of recovery of hydrometallurgical waste residues, and particularly relates to a method for reducing and leaching manganese and lead from electrolytic manganese anode slag by alkali activation of sulfur powder. Background Art

[0002] The anode slag of electrolytic manganese is the waste residue generated at the anode during the production of electrolytic metallic manganese. Its main component is manganese, with the content of manganese dioxide accounting for about 40-50%, and the lead content is also relatively high, accounting for about 4-6%. Both are valuable secondary resources that can be reused. However, the mineral composition and structure of electrolytic manganese anode slag are complex, and the symbiotic relationship between lead and manganese hydrated oxides is very close. It is difficult to separate manganese and lead by mechanical separation methods. Therefore, at present, except for a small amount used in the smelting of ferromanganese and silicomanganese alloys, most of them are piled up and have not been well developed and comprehensively utilized, which not only causes waste of resources, but also is prone to environmental pollution if not properly treated. Therefore, how to efficiently separate and comprehensively utilize the main valuable components, manganese and lead, in electrolytic manganese anode slag economically and environmentally is an urgent problem to be solved by those skilled in the art.

[0003] The existing methods for resource utilization of electrolytic manganese anode mud mainly include the reduction method and the activated anode slag method, which have problems such as high operating costs, easy secondary pollution, and inability to be industrially promoted. The reduction method uses charcoal, graphite, etc. as reducing agents for high-temperature roasting reactions or uses biomass, sulfurous acid, pyrite, sulfur dioxide, etc. as reducing agents to convert tetravalent manganese in the anode mud into divalent manganese and enter the solution, while impurities such as lead exist in the solid phase. Solid-liquid separation can achieve the comprehensive utilization of manganese. However, the high-temperature roasting process requires high energy consumption, is prone to environmental pollution, and will cause a large increase in operating costs. The activated anode slag method removes impurity elements in the anode slag through acid leaching, roasting acid leaching, alkali oxidation, etc., changes the crystal form of manganese dioxide in the anode slag, and then promotes the regeneration of manganese sesquioxide or permanganate into manganese dioxide through hydrogen ions or reducing agents to obtain activated manganese dioxide products. The products are prone to secondary pollution and have high operating costs, and cannot be industrially promoted.

[0004] The method for preparing manganese sulfate electrolyte and recovering lead from electrolytic manganese anode slime disclosed in CN201410054653.8 uses electrolytic manganese anode slime, sulfur ore dressing concentrate with sulfur content ≥ 45% and concentrated sulfuric acid as raw materials. Through reduction leaching, impurity removal and filtration, manganese sulfate electrolyte is obtained. Taking the leaching residue as raw material, through processing, sulfur ore dressing concentrate with sulfur content ≥ 45%, hydrochloric acid and nitric acid are used as raw materials. Through reduction leaching, impurity removal and filtration, the filter residue is qualified lead concentrate. Although this method has the characteristics of less consumption of the reducing agent pyrite, low cost, and the ability to recycle manganese and lead, there are also defects: on the one hand, a large amount of waste residue is generated during the leaching process, and the waste residue needs to be further treated, increasing the treatment cost; on the other hand, the iron content in the leaching solution is high, resulting in the need to adopt a complex purification process to obtain qualified manganese sulfate solution later.

[0005] Therefore, it is an urgent problem for those skilled in the art to provide a method for reduction leaching of electrolytic manganese anode slag with low operating cost and no secondary pollution. Summary of the Invention

[0006] The purpose of the present invention is to solve the technical problems of high manganese leaching cost and secondary pollution generated during the leaching process in the prior art, and provide a method for recovering manganese and lead by reduction leaching of electrolytic manganese anode slag with activated sulfur powder with alkali. This method has the advantages of wide source of reducing agent, low price, simple process, high leaching rate of manganese and lead, low operating cost, no secondary waste residue pollution and waste gas pollution, etc.

[0007] The technical solution adopted by the present invention is as follows: A method for recovering manganese and lead by reduction leaching of electrolytic manganese anode slag with activated sulfur powder with alkali includes the following steps:

[0008] S1. Mix electrolytic manganese anode slag, sulfur powder and solid alkali, and obtain activated reduction raw material through heating activation;

[0009] S2. Leach the activated reduction raw material with dilute sulfuric acid, and obtain manganese-containing leaching solution and leaching residue containing lead sulfate after liquid-solid separation;

[0010] S3. Leach the leaching residue with chloride salt solution, and obtain lead-containing solution and leaching residue after liquid-solid separation.

[0011] Preferably, the solid alkali is one or two of sodium hydroxide and potassium hydroxide.

[0012] Preferably, the mass ratio of the sulfur powder to the electrolytic manganese anode slag is (0.10 - 0.15):1.0; the mass ratio of the solid alkali to the electrolytic manganese anode slag is (0.5 - 1.5):1.0.

[0013] Preferably, the temperature of heating activation in S1 is 30 - 90 °C, and the time is 0.1 - 1.0 h.

[0014] Preferably, in S2, the concentration of dilute sulfuric acid is 0.1-1.0 mol / L, the volume-mass ratio of the leaching intermediate liquid to solid is (1-3) L: 1 Kg, the leaching temperature is 15-30 °C, and the leaching time is 0.5-1 h.

[0015] More preferably, the chloride salt solution is one or more of sodium chloride, potassium chloride, and calcium chloride.

[0016] More preferably, in S3, the concentration of the chloride salt solution is 1.0-5.0 mol / L, the volume-mass ratio of the leaching intermediate liquid to solid is (1-3) L: 1 Kg, the leaching temperature is 30-90 °C, and the leaching time is 0.5-5.0 h.

[0017] The beneficial effects of the present invention are as follows:

[0018] 1. The present invention first uses sulfur powder and alkali to reduce manganese dioxide in electrolytic manganese anode slag. After leaching with dilute acid, the obtained manganese sulfate is dissolved in water, and some metals with a small precipitation pH such as iron remain in the slag, realizing leaching separation; using sulfur powder as a reducing agent can effectively improve the reduction rate of manganese in an alkaline environment; using chloride salt to leach lead-containing slag significantly improves the lead leaching rate, and the impurity concentration in the leaching solution is low; no secondary waste residue pollution and waste gas pollution are generated during the whole process, effectively reducing environmental pollution.

[0019] 2. The reducing agent in the present invention has a wide source, low price, simple process steps, easy operation, and is suitable for large-scale industrial production. Description of the Drawings

[0020] Figure 1 It is a flow chart of the method of the present invention. Detailed Embodiments

[0021] The present invention will be further described below in conjunction with the drawings and specific embodiments.

[0022] Example 1

[0023] Weigh 1 Kg of electrolytic manganese anode slag, 0.15 Kg of sulfur powder, and 0.5 Kg of solid sodium hydroxide respectively, stir until evenly mixed, heat to 30 °C for activation reduction for 1.0 h to obtain an activated reduction raw material. Add 0.1 mol / L dilute sulfuric acid to the activated reduction raw material to adjust the pulp to a liquid-solid ratio of 3 L: 1 Kg, stir and leach at room temperature for 1 h, filter to obtain a manganese-containing leaching solution and a lead-containing leaching residue, and the leaching rate of manganese is 96.0%. Add a 4.0 mol / L sodium chloride solution to the leaching residue to adjust the pulp to a liquid-solid ratio of 3 L: 1 Kg, stir and leach at room temperature for 1 h, filter to obtain a lead-containing leaching solution and a leaching residue, and the leaching rate of lead is 92.6%.

[0024] Example 2

[0025] Weigh 1 Kg of electrolytic manganese anode slag, 0.1 Kg of sulfur powder and 0.75 Kg of solid potassium hydroxide respectively, stir until evenly mixed, heat to 50 °C for activation reduction for 1.0 h to obtain an activated reduction raw material. Add 0.5 mol / L dilute sulfuric acid to the activated reduction raw material to adjust the pulp to a liquid-solid ratio of 2 L:1 Kg, stir and leach at room temperature for 1 h, filter to obtain a manganese-containing leaching solution and a lead-containing leaching residue, and the leaching rate of manganese is 96.9%. Add a 4.0 mol / L sodium chloride-calcium chloride solution to the leaching residue to adjust the pulp to a liquid-solid ratio of 4 L:1 Kg, stir and leach at room temperature for 1 h, filter to obtain a lead-containing leaching solution and a leaching residue, and the leaching rate of lead is 93.4%.

[0026] Example 3

[0027] Weigh 1 Kg of electrolytic manganese anode slag, 0.12 Kg of sulfur powder and 1.0 Kg of solid sodium hydroxide respectively, stir until evenly mixed, heat to 80 °C for activation reduction for 0.5 h to obtain an activated reduction raw material. Add 0.75 mol / L dilute sulfuric acid to the activated reduction raw material to adjust the pulp to a liquid-solid ratio of 2 L:1 Kg, stir and leach at room temperature for 3.0 h, filter to obtain a manganese-containing leaching solution and a lead-containing leaching residue, and the leaching rate of manganese is 97.9%. Add a 5.0 mol / L potassium chloride-calcium chloride solution to the leaching residue to adjust the pulp to a liquid-solid ratio of 2 L:1 Kg, stir and leach at room temperature for 2.0 h, filter to obtain a lead-containing leaching solution and a leaching residue, and the leaching rate of lead is 96.4%.

[0028] Example 4

[0029] Weigh 1 Kg of electrolytic manganese anode slag, 0.13 Kg of sulfur powder and 1.0 Kg of solid potassium hydroxide respectively, stir until evenly mixed, heat to 90 °C for activation reduction for 0.5 h to obtain an activated reduction raw material. Add 1.0 mol / L dilute sulfuric acid to the activated reduction raw material to adjust the pulp to a liquid-solid ratio of 3 L:1 Kg, stir and leach at room temperature for 0.8 h, filter to obtain a manganese-containing leaching solution and a lead-containing leaching residue, and the leaching rate of manganese is 96.8%. Add a 2.0 mol / L sodium chloride - 2.0 mol / L calcium chloride solution to the leaching residue to adjust the pulp to a liquid-solid ratio of 2.5 L:1 Kg, stir and leach at room temperature for 1 h, filter to obtain a lead-containing leaching solution and a leaching residue, and the leaching rate of lead is 95.4%.

[0030] Example 5

[0031] Weigh 1 Kg of electrolytic manganese anode slag, 0.14 Kg of sulfur powder and 0.5 Kg of solid sodium hydroxide - 0.5 Kg of potassium hydroxide respectively, stir until evenly mixed, heat to 90 °C for activation reduction for 0.1 h to obtain an activated reduction raw material. Add 0.8 mol / L dilute sulfuric acid to the activated reduction raw material to adjust the pulp to a liquid-solid ratio of 3 L:1 Kg, stir and leach at room temperature for 1.0 h, filter to obtain a manganese-containing leaching solution and a lead-containing leaching residue, and the leaching rate of manganese is 97.8%. Add a 2.0 mol / L potassium chloride - 2.0 mol / L calcium chloride solution to the leaching residue to adjust the pulp to a liquid-solid ratio of 3 L:1 Kg, stir and leach at room temperature for 1 h, filter to obtain a lead-containing leaching solution and a leaching residue, and the leaching rate of lead is 96.5%.

[0032] The description and drawings of the present invention are considered to be illustrative rather than restrictive. Based on the present invention, those skilled in the art can make some substitutions and deformations to some technical features without creative labor according to the disclosed technical content, and all are within the protection scope of the present invention.

Claims

1. A method for recovering manganese and lead from electrolytic manganese anode slag by reduction leaching with alkali-activated sulfur powder, characterized in that, It includes the following steps: S1. Mix electrolytic manganese anode slag, sulfur powder and solid base, and obtain an activated reducing raw material through heating activation; S2. Leach the activated reducing raw material with dilute sulfuric acid, and obtain a manganese-containing leaching solution and a leaching residue containing lead sulfate after liquid-solid separation; S3. Leach the leaching residue with a chloride salt solution, and obtain a lead-containing solution and a leaching residue after liquid-solid separation.

2. The method according to claim 1, wherein The solid base is one or two of sodium hydroxide and potassium hydroxide.

3. The method according to claim 1, characterized in that The mass ratio of the sulfur powder to the electrolytic manganese anode slag is (0.10-0.15):1.0; the mass ratio of the solid base to the electrolytic manganese anode slag is (0.5-1.5):1.

0.

4. The method according to claim 1, wherein In S1, the temperature of heating activation is 30-90°C, and the time is 0.1-1.0 h.

5. The method according to claim 1, characterized in that, In S2, the concentration of the dilute sulfuric acid is 0.1-1.0 mol / L, the volume-mass ratio of liquid to solid in the leaching is (1-3) L:1 Kg, the leaching temperature is 15-30°C, and the leaching time is 0.5-1 h.

6. The method according to claim 1, characterized in that The chloride salt solution is one or several of sodium chloride, potassium chloride and calcium chloride.

7. The method according to claim 1, characterized in that, In S3, the concentration of the chloride salt solution is 1.0-5.0 mol / L, the volume-mass ratio of liquid to solid in the leaching is (1-3) L:1 Kg, the leaching temperature is 30-90°C, and the leaching time is 0.5-5.0 h.

Images