Method for purifying manganese electrolysis anolyte and utilizing purified slag

Abstract

The invention provides a manganese electrolysis anolyte purification and purification residue utilization method which comprises the following steps: adding sodium fluoride into a manganese electrolysis anolyte for precipitation and purification to obtain a purification solution and purification residues; adding a sodium hydroxide solution into the purified slag, and carrying out wet grinding alkali transfer to obtain alkali transfer slag and alkali transfer liquid; adding sulfuric acid into the alkali transfer slag for acid leaching to obtain magnesium sulfate and calcium sulfate slag; adding hydrofluoric acid into the alkali transfer solution for neutralization to obtain a neutralized solution; the neutralization liquid is subjected to evaporative crystallization, sodium fluoride is obtained, and the sodium fluoride is used for precipitation purification. According to the method, the manganese electrolysis anolyte is precipitated and purified through sodium fluoride to separate calcium and magnesium elements and manganese ions, then the calcium element and the magnesium element are separated through sodium hydroxide solution wet ball milling and sulfuric acid leaching, and the starting material sodium fluoride is recycled, so that waste liquid generated in the technological process is reduced, and the production cost is reduced. The cyclic utilization of resources is promoted, and the concept of green sustainable development is met.

Description

Technical Field

[0001] The invention belongs to the technical field of resource recycling, and in particular relates to a method for purifying manganese electrolysis anode liquid and utilizing purified slag. Background Art

[0002] Metallic manganese is widely used in metallurgy, medicine, electronics, communications and other fields, and electrolysis is the main way to produce manganese. In the manganese electrolysis process, the anolyte needs to circulate in a closed loop, and the magnesium ions in the anolyte will gradually accumulate during the circulation process. When the magnesium ion concentration reaches a certain level, it will lead to a decrease in current efficiency and an increase in production costs. In addition, magnesium ions will also co-crystallize with manganese sulfate and ammonium sulfate, causing the loss of beneficial components in the electrolyte, and even blocking the circulation pipeline, affecting the continuity of manganese electrolysis production. In an electrolytic cell with a diaphragm, the deposition of magnesium sulfate will also block the diaphragm and accelerate the scrapping of the diaphragm. Therefore, it is necessary to regularly treat the manganese electrolysis anolyte. The manganese electrolysis anolyte is rich in manganese, calcium, magnesium and other elements, and has important recycling value. Therefore, effective purification and resource utilization of the manganese electrolysis anolyte has high economic and social value.

[0003] That is, how to provide a method for purifying manganese electrolytic anolyte and utilizing purified slag, purifying the manganese electrolytic anolyte by precipitation of sodium fluoride, and separating the calcium and magnesium ions in the purified slag by wet grinding alkali conversion and sulfuric acid leaching, so as to realize the resource utilization of manganese electrolytic anolyte, is a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0004] The object of the present invention is to provide a method for purifying manganese electrolysis anolyte and utilizing the purified slag, so as to solve at least one of the above technical problems.

[0005] To achieve the above-mentioned purpose, the first aspect of the present invention provides a method for purifying manganese electrolytic anolyte and utilizing purified slag, the method comprising the following steps: S1, adding sodium fluoride to the manganese electrolytic anolyte for precipitation purification to obtain purified liquid and purified slag; the purified liquid is used to leach manganese ore; S2, adding sodium hydroxide solution to the purified slag for wet grinding and alkali conversion to obtain alkali conversion slag and alkali conversion liquid; S3, adding sulfuric acid to the alkali conversion slag for acid leaching to obtain magnesium sulfate and calcium sulfate slag; S4, adding hydrofluoric acid to the alkali conversion liquid for neutralization to obtain neutralized liquid; S5, evaporating and crystallizing the neutralized liquid to obtain sodium fluoride, and the sodium fluoride is used in the precipitation purification.

[0006] In the first aspect, in S1, the amount of sodium fluoride added is 1.2-1.6 times the theoretical reaction molar ratio of calcium and magnesium elements in the manganese electrolysis anolyte.

[0007] In the first aspect, in S1, the process parameters of the precipitation purification include: precipitation purification time is 0.2-2h, precipitation purification temperature is 20-40°C, and stirring speed is 200-400r / min.

[0008] In the first aspect, in S2, the concentration of the sodium hydroxide solution is 20-40 mol / L.

[0009] In the first aspect, in S2, the process parameters of the wet milling alkali conversion include: a liquid-to-solid ratio of 8-16 mL / g, a ball-to-material ratio of 10:1-18:1, a ball milling time of 0.5-2.5 h, and a ball milling speed of 400-800 r / min.

[0010] In the first aspect, in S3, the amount of sulfuric acid used is 1.5-2.0 times the theoretical reaction molar ratio of calcium and magnesium elements in the alkali-converted slag.

[0011] In the first aspect, in S3, the process parameters of the acid leaching include: acid leaching time of 0.2-2h, liquid-solid ratio of 8-14mL / g, and acid leaching temperature of 25-50°C.

[0012] In the first aspect, in S5, the temperature of the evaporative crystallization is 100-110°C.

[0013] Beneficial effects:

[0014] The invention provides a method for purifying manganese electrolytic anolyte and utilizing purified slag. Firstly, sodium fluoride is added to the manganese electrolytic anolyte for precipitation purification, so that calcium and magnesium ions in the manganese electrolytic anolyte form fluoride precipitation and enter the purified slag, while manganese ions in the manganese electrolytic anolyte enter the purified liquid, and can be recovered for leaching manganese ore; secondly, sodium hydroxide solution is added to the purified slag for wet grinding and alkali conversion, and calcium and magnesium ion precipitation and fluoride ion solution are gradually separated by wet ball milling, so that the calcium and magnesium ion precipitation enters the alkali conversion slag, and the fluoride ion solution enters the alkali conversion liquid, laying a foundation for subsequent processes; then, sulfuric acid is added to the alkali conversion slag for acid leaching, and calcium ions and magnesium ions are separated by sulfuric acid acid leaching to form magnesium sulfate solution and calcium sulfate slag; finally, hydrofluoric acid is added to the alkali conversion liquid for neutralization to obtain sodium fluoride neutralization solution, and the neutralization solution is evaporated and crystallized to obtain sodium fluoride solid, and the obtained sodium fluoride solid can be used as a starting material to precipitate and purify calcium and magnesium ions in the manganese electrolytic anolyte, thereby realizing the recycling of sodium fluoride. The present invention first precipitates and purifies manganese electrolysis anolyte by sodium fluoride to separate calcium, magnesium and manganese ions, then separates calcium and magnesium by sodium hydroxide solution wet ball milling and sulfuric acid leaching, and recycles the starting material sodium fluoride, thereby reducing the generation of waste liquid in the process flow, promoting the recycling of resources, and complying with the concept of green and sustainable development.

[0015] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A process for purifying manganese electrolysis anode liquid and utilizing purified slag provided by the present invention Figure 1 ;

[0018] Figure 2 A process for purifying manganese electrolysis anode liquid and utilizing purified slag provided by the present invention Figure 2 . DETAILED DESCRIPTION

[0019] The present invention will be described in detail below in conjunction with specific implementations and examples, and the advantages and various effects of the present invention will be more clearly presented. It should be understood by those skilled in the art that these specific implementations and examples are used to illustrate the present invention, rather than to limit the present invention.

[0020] Throughout the specification, unless otherwise specifically stated, the terms used herein should be understood as meanings commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art to which the present invention belongs. In the event of a conflict, the present specification takes precedence.

[0021] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or obtained by existing methods.

[0022] See also Figure 1-2The present application provides a method for purifying manganese electrolytic anode liquid and utilizing purified slag, the method comprising the following steps: S1, adding sodium fluoride to the manganese electrolytic anode liquid for precipitation purification to obtain purified liquid and purified slag; the purified liquid is used to leach manganese ore; S2, adding sodium hydroxide solution to the purified slag for wet grinding and alkali conversion to obtain alkali conversion slag and alkali conversion liquid; S3, adding sulfuric acid to the alkali conversion slag for acid leaching to obtain magnesium sulfate and calcium sulfate slag; S4, adding hydrofluoric acid to the alkali conversion liquid for neutralization to obtain a neutralized liquid; S5, evaporating and crystallizing the neutralized liquid to obtain sodium fluoride, and the sodium fluoride is used in the precipitation purification.

[0023] Specifically, the present invention provides a method for purifying manganese electrolytic anolyte and utilizing purified slag. First, sodium fluoride is added to the manganese electrolytic anolyte for precipitation purification, so that calcium and magnesium ions in the manganese electrolytic anolyte form fluoride precipitation and enter the purified slag, while manganese ions in the manganese electrolytic anolyte enter the purified liquid, which can be recovered for leaching manganese ore; secondly, sodium hydroxide solution is added to the purified slag for wet grinding and alkali conversion, and calcium and magnesium ion precipitation and fluoride ion solution are gradually separated by wet ball milling, so that the calcium and magnesium ion precipitation enters the alkali conversion slag, and the fluoride ion solution enters the alkali conversion liquid, laying a foundation for subsequent processes; then, sulfuric acid is added to the alkali conversion slag for acid leaching, and calcium ions and magnesium ions are separated by sulfuric acid acid leaching to form magnesium sulfate solution and calcium sulfate slag; finally, hydrofluoric acid is added to the alkali conversion liquid for neutralization to obtain sodium fluoride neutralization solution, and the neutralization solution is evaporated and crystallized to obtain sodium fluoride solid, and the obtained sodium fluoride solid can be used as a starting material to precipitate and purify calcium and magnesium ions in the manganese electrolytic anolyte, thereby realizing the recycling of sodium fluoride. The present invention first precipitates and purifies manganese electrolysis anolyte by sodium fluoride to separate calcium, magnesium and manganese ions, then separates calcium and magnesium by sodium hydroxide solution wet ball milling and sulfuric acid leaching, and recycles the starting material sodium fluoride, thereby reducing the generation of waste liquid in the process flow, promoting the recycling of resources, and complying with the concept of green and sustainable development.

[0024] In some possible embodiments, in S1, the amount of sodium fluoride added is 1.2-1.6 times the theoretical reaction molar ratio of calcium and magnesium elements in the manganese electrolysis anode liquid.

[0025] In some possible embodiments, in S1, the process parameters of the precipitation purification include: precipitation purification time is 0.2-2h, precipitation purification temperature is 20-40°C, and stirring speed is 200-400r / min.

[0026] Those skilled in the art can understand that the manganese electrolytic anolyte is rich in manganese, calcium, magnesium and other elements. By adding sodium fluoride to the manganese electrolytic anolyte, calcium and magnesium elements are precipitated from the manganese electrolytic anolyte to form a fluoride slag precipitate. At this time, the manganese electrolytic anolyte is rich in manganese elements and can be used in the manganese ore leaching process to recycle the manganese elements in the manganese electrolytic anolyte; by controlling the amount of sodium fluoride added, incomplete precipitation of calcium and magnesium and precipitation of manganese ions from the manganese electrolytic anolyte can be avoided.

[0027] In some possible embodiments, in S2, the concentration of the sodium hydroxide solution is 20-40 mol / L.

[0028] In some possible embodiments, in S2, the process parameters of the wet milling alkali conversion include: a liquid-to-solid ratio of 8-16 mL / g, a ball-to-material ratio of 10:1-18:1, a ball milling time of 0.5-2.5 h, and a ball milling speed of 400-800 r / min.

[0029] This is because, wet ball milling of the purified slag with sodium hydroxide solution as solvent can gradually release the fluoride ions in the purified slag, allowing them to enter the alkali-to-liquid conversion, laying the foundation for the subsequent preparation of sodium fluoride; at the same time, controlling the concentration of the sodium hydroxide solution, the liquid-to-solid ratio, the ball-to-material ratio, the ball milling time and the ball milling speed in the wet ball milling process can separate the fluoride ions from the purified slag to the maximum extent and increase the yield of sodium fluoride.

[0030] In some possible embodiments, in S3, the amount of sulfuric acid used is 1.5-2.0 times the theoretical reaction molar ratio of calcium and magnesium elements in the alkali-converted slag.

[0031] In some possible embodiments, in S3, the process parameters of the acid leaching include: acid leaching time of 0.2-2h, liquid-to-solid ratio of 8-14mL / g, and acid leaching temperature of 25-50°C.

[0032] Those skilled in the art can understand that the solubility of magnesium sulfate is greater than that of calcium sulfate. The calcium and magnesium elements can be separated from the alkali-converted slag by acid leaching with sulfuric acid, so that the magnesium element is dissolved from the alkali-converted slag to form a magnesium sulfate solution, which can then be used to prepare high-purity magnesium sulfate through evaporation and crystallization, while the calcium element forms a precipitate in the calcium sulfate slag, which can then be collected and used to prepare building materials.

[0033] In some possible embodiments, in S5, the temperature of the evaporation crystallization is 100-110°C.

[0034] This is because impurities in the sodium fluoride neutralization solution can be removed by evaporation and crystallization, and when used as a starting material, it promotes the precipitation and purification of the manganese electrolysis anolyte.

[0035] The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are intended only to illustrate the present application and are not intended to limit the scope of the present application. The experimental methods for which specific conditions are not specified in the following examples are usually measured according to national standards. If there is no corresponding national standard, then the conditions recommended by the manufacturer are followed.

[0036] Example 1

[0037] A method for purifying manganese electrolysis anolyte and utilizing purified slag, specifically comprising the following steps:

[0038] (1) Purification by precipitation: adding sodium fluoride to the manganese electrolytic anolyte for purification by precipitation to obtain purified liquid and purified slag; wherein the purified liquid is centrally treated and can be used to leaching manganese ore; the amount of sodium fluoride added is 1.2 times the theoretical reaction molar ratio of calcium and magnesium elements in the manganese electrolytic anolyte, the purification time is 0.2h, the purification temperature is 20°C, and the stirring speed is 200r / min;

[0039] (2) Wet milling and alkali conversion: adding sodium hydroxide solution to the purified slag for wet milling and alkali conversion to obtain alkali conversion slag and alkali conversion liquid; the concentration of the sodium hydroxide solution is 20 mol / L, the liquid-to-solid ratio is 8 mL / g, the ball-to-material ratio is 10:1, the ball milling time is 2 h, and the ball milling speed is 400 r / min;

[0040] (3) Acid leaching: adding sulfuric acid to the alkali-converted slag for acid leaching to obtain magnesium sulfate and calcium sulfate slag; wherein the amount of sulfuric acid used is 1.5 times the theoretical reaction molar ratio of calcium and magnesium elements in the alkali-converted slag, the acid leaching time is 0.2h, the liquid-solid ratio is 8mL / g, the acid leaching temperature is 25°C, and the calcium sulfate slag is centrally processed and can be used for building materials;

[0041] (4) Neutralization: adding hydrofluoric acid to the alkali conversion liquid for neutralization to obtain a neutralized solution;

[0042] (5) Evaporation and crystallization: The neutralized solution is evaporated and crystallized at a temperature of 105° C. to obtain sodium fluoride, wherein the sodium fluoride can be used as a raw material for precipitation and purification of manganese electrolysis anode liquid.

[0043] The test results show that the recovery rate of magnesium is 98.40%, the purity of magnesium sulfate is 96.32%, the recovery rate of fluorine is 95.30%, and the purity of sodium fluoride is 90.50%.

[0044] Example 2

[0045] A method for purifying manganese electrolysis anolyte and utilizing purified slag, specifically comprising the following steps:

[0046] (1) Purification by precipitation: adding sodium fluoride to the manganese electrolytic anolyte for purification by precipitation to obtain purified liquid and purified slag; wherein the purified liquid is centrally treated and can be used to leaching manganese ore; the amount of sodium fluoride added is 1.6 times the theoretical reaction molar ratio of calcium and magnesium elements in the manganese electrolytic anolyte, the purification time is 1.0 h, the purification temperature is 25° C., and the stirring speed is 250 r / min;

[0047] (2) Wet milling and alkali conversion: adding sodium hydroxide solution to the purified slag for wet milling and alkali conversion to obtain alkali conversion slag and alkali conversion liquid; the concentration of the sodium hydroxide solution is 25 mol / L, the liquid-to-solid ratio is 14 mL / g, the ball-to-material ratio is 12:1, the ball milling time is 1.5 h, and the ball milling speed is 600 r / min;

[0048] (3) Acid leaching: adding sulfuric acid to the alkali-converted slag for acid leaching to obtain magnesium sulfate and calcium sulfate slag; wherein the amount of sulfuric acid used is 2.0 times the theoretical reaction molar ratio of calcium and magnesium elements in the alkali-converted slag, the acid leaching time is 1 hour, the liquid-solid ratio is 12 mL / g, the acid leaching temperature is 35°C, and the calcium sulfate slag is centrally processed and can be used for building materials;

[0049] (4) Neutralization: adding hydrofluoric acid to the alkali conversion liquid for neutralization to obtain a neutralized solution;

[0050] (5) Evaporation and crystallization: The neutralized solution is evaporated and crystallized at a temperature of 105° C. to obtain sodium fluoride, wherein the sodium fluoride can be used as a raw material for precipitation and purification of manganese electrolysis anode liquid.

[0051] The test results show that the recovery rate of magnesium is 98.78%, the purity of magnesium sulfate is 94.15%, the recovery rate of fluorine is 96.23%, and the purity of sodium fluoride is 90.29%.

[0052] Example 3

[0053] A method for purifying manganese electrolysis anolyte and utilizing purified slag, specifically comprising the following steps:

[0054] (1) Purification by precipitation: adding sodium fluoride to the manganese electrolytic anolyte for purification by precipitation to obtain purified liquid and purified slag; wherein the purified liquid is centrally treated and can be used to leaching manganese ore; the amount of sodium fluoride added is 1.4 times the theoretical reaction molar ratio of calcium and magnesium elements in the manganese electrolytic anolyte, the purification time is 1.5 h, the purification temperature is 30° C., and the stirring speed is 300 r / min;

[0055] (2) Wet milling and alkali conversion: adding sodium hydroxide solution to the purified slag for wet milling and alkali conversion to obtain alkali conversion slag and alkali conversion liquid; the concentration of the sodium hydroxide solution is 30 mol / L, the liquid-to-solid ratio is 16 mL / g, the ball-to-material ratio is 14:1, the ball milling time is 1 h, and the ball milling speed is 700 r / min;

[0056] (3) Acid leaching: adding sulfuric acid to the alkali-converted slag for acid leaching to obtain magnesium sulfate and calcium sulfate slag; wherein the amount of sulfuric acid used is 2.0 times the theoretical reaction molar ratio of calcium and magnesium elements in the alkali-converted slag, the acid leaching time is 1 hour, the liquid-solid ratio is 12 mL / g, the acid leaching temperature is 40°C, and the calcium sulfate slag is centrally processed and can be used for building materials;

[0057] (4) Neutralization: adding hydrofluoric acid to the alkali conversion liquid for neutralization to obtain a neutralized solution;

[0058] (5) Evaporation and crystallization: The neutralized solution is evaporated and crystallized at a temperature of 105° C. to obtain sodium fluoride, wherein the sodium fluoride can be used as a raw material for precipitation and purification of manganese electrolysis anode liquid.

[0059] The test results show that the recovery rate of magnesium is 98.52%, the purity of magnesium sulfate is 95.32%, the recovery rate of fluorine is 97.13%, and the purity of sodium fluoride is 91.45%.

[0060] Example 4

[0061] A method for purifying manganese electrolysis anolyte and utilizing purified slag, specifically comprising the following steps:

[0062] (1) Precipitation purification: sodium fluoride is added to the manganese electrolytic anolyte for precipitation purification to obtain a purified liquid and a purified slag; wherein the purified liquid is centrally treated and can be used to leaching manganese ore; the amount of sodium fluoride added is 1.6 times the theoretical reaction molar ratio of calcium and magnesium elements in the manganese electrolytic anolyte, the precipitation purification time is 2 hours, the precipitation purification temperature is 30° C., and the stirring speed is 400 r / min;

[0063] (2) Wet milling and alkali conversion: adding sodium hydroxide solution to the purified slag for wet milling and alkali conversion to obtain alkali conversion slag and alkali conversion liquid; the concentration of the sodium hydroxide solution is 35 mol / L, the liquid-to-solid ratio is 10 mL / g, the ball-to-material ratio is 16:1, the ball milling time is 1 h, and the ball milling speed is 500 r / min;

[0064] (3) Acid leaching: adding sulfuric acid to the alkali-converted slag for acid leaching to obtain magnesium sulfate and calcium sulfate slag; wherein the amount of sulfuric acid used is 1.7 times the theoretical reaction molar ratio of calcium and magnesium elements in the alkali-converted slag, the acid leaching time is 2 hours, the liquid-solid ratio is 12 mL / g, the acid leaching temperature is 35°C, and the calcium sulfate slag is centrally processed and can be used for building materials;

[0065] (4) Neutralization: adding hydrofluoric acid to the alkali conversion liquid for neutralization to obtain a neutralized solution;

[0066] (5) Evaporation and crystallization: The neutralized solution is evaporated and crystallized at a temperature of 105° C. to obtain sodium fluoride, wherein the sodium fluoride can be used as a raw material for precipitation and purification of manganese electrolysis anode liquid.

[0067] The test results show that the recovery rate of magnesium is 98.98%, the purity of magnesium sulfate is 92.95%, the recovery rate of fluorine is 96.65%, and the purity of sodium fluoride is 92.22%.

[0068] Example 5

[0069] A method for purifying manganese electrolysis anolyte and utilizing purified slag, specifically comprising the following steps:

[0070] (1) Precipitation purification: sodium fluoride is added to the manganese electrolytic anolyte for precipitation purification to obtain a purified liquid and a purified slag; wherein the purified liquid is centrally treated and can be used to leaching manganese ore; the amount of sodium fluoride added is 1.2 times the theoretical reaction molar ratio of calcium and magnesium elements in the manganese electrolytic anolyte, the precipitation purification time is 1 hour, the precipitation purification temperature is 40° C., and the stirring speed is 400 r / min;

[0071] (2) Wet milling and alkali conversion: adding sodium hydroxide solution to the purified slag for wet milling and alkali conversion to obtain alkali conversion slag and alkali conversion liquid; the concentration of the sodium hydroxide solution is 40 mol / L, the liquid-to-solid ratio is 12 mL / g, the ball-to-material ratio is 18:1, the ball milling time is 0.5 h, and the ball milling speed is 500 r / min;

[0072] (3) Acid leaching: adding sulfuric acid to the alkali-converted slag for acid leaching to obtain magnesium sulfate and calcium sulfate slag; wherein the amount of sulfuric acid used is 2.0 times the theoretical reaction molar ratio of calcium and magnesium elements in the alkali-converted slag, the acid leaching time is 1 hour, the liquid-solid ratio is 12 mL / g, the acid leaching temperature is 35°C, and the calcium sulfate slag is centrally processed and can be used for building materials;

[0073] (4) Neutralization: adding hydrofluoric acid to the alkali conversion liquid for neutralization to obtain a neutralized solution;

[0074] (5) Evaporation and crystallization: The neutralized solution is evaporated and crystallized at a temperature of 105° C. to obtain sodium fluoride, wherein the sodium fluoride can be used as a raw material for precipitation and purification of manganese electrolysis anode liquid.

[0075] The test results show that the recovery rate of magnesium is 97.78%, the purity of magnesium sulfate is 93.32%, the recovery rate of fluorine is 96.00%, and the purity of sodium fluoride is 91.23%.

[0076] In summary, compared with the prior art, the technical solution provided by the present invention has the following advantages:

[0077] (1) The present invention uses sodium fluoride to precipitate and purify the manganese electrolysis anolyte, efficiently separates calcium and magnesium elements from manganese elements, and recycles the recovered sodium fluoride in subsequent processes;

[0078] (2) The present invention solves the problem of calcium and magnesium coexisting and being difficult to separate by sulfuric acid leaching, realizes the separation of calcium and magnesium elements, and lays a foundation for the preparation of high-purity magnesium sulfate, as well as the use of calcium elements in the production of building materials;

[0079] (3) The method provided by the present invention is simple to operate, can effectively separate calcium and magnesium elements, and reduces the treatment of waste liquid in the process, thereby realizing the recycling of resources.

[0080] Finally, it should be noted that the terms "comprises," "includes," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements that are inherent to such process, method, article, or apparatus.

[0081] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0082] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for purifying manganese electrolysis anolyte and utilizing purified slag, characterized in that: The method comprises the following steps: S1, adding sodium fluoride to the manganese electrolysis anolyte for precipitation purification to obtain a purified liquid and purified slag; the purified liquid is used to leaching manganese ore; S2, adding sodium hydroxide solution to the purified slag, performing wet grinding and alkali conversion to obtain alkali conversion slag and alkali conversion liquid; S3, adding sulfuric acid to the alkali-converted slag for acid leaching to obtain magnesium sulfate and calcium sulfate slag; S4, adding hydrofluoric acid to the alkali-converted liquid for neutralization to obtain a neutralized solution; S5. Evaporating and crystallizing the neutralized solution to obtain sodium fluoride, which is used in the precipitation purification.

2. The method for purifying manganese electrolysis anolyte and utilizing purified slag according to claim 1, characterized in that: In S1, the amount of sodium fluoride added is 1.2-1.6 times the theoretical reaction molar ratio of calcium and magnesium elements in the manganese electrolysis anolyte.

3. The method for purifying manganese electrolysis anolyte and utilizing purified slag according to claim 1, characterized in that: In S1, the process parameters of the precipitation purification include: precipitation purification time is 0.2-2h, precipitation purification temperature is 20-40°C, and stirring speed is 200-400r / min.

4. The method for purifying manganese electrolysis anolyte and utilizing purified slag according to claim 1, characterized in that: In S2, the concentration of the sodium hydroxide solution is 20-40 mol / L.

5. The method for purifying manganese electrolysis anolyte and utilizing purified slag according to claim 1, characterized in that: In S2, the process parameters of the wet milling alkali conversion include: liquid-solid ratio of 8-16 mL / g, ball-to-material ratio of 10:1-18:1, ball milling time of 0.5-2.5 h, and ball milling speed of 400-800 r / min.

6. The method for purifying manganese electrolysis anolyte and utilizing purified slag according to claim 1, characterized in that: In S3, the amount of sulfuric acid used is 1.5-2.0 times the theoretical reaction molar ratio of calcium and magnesium elements in the alkali-converted slag.

7. The method for purifying manganese electrolysis anolyte and utilizing purified slag according to claim 1, characterized in that: In S3, the process parameters of the acid leaching include: acid leaching time of 0.2-2h, liquid-to-solid ratio of 8-14mL / g, and acid leaching temperature of 25-50°C.

8. The method for purifying manganese electrolysis anolyte and utilizing purified slag according to claim 1, characterized in that: In S5, the temperature of the evaporation crystallization is 100-110°C.

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