CN116375094A - Method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur - Google Patents
Method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur Download PDFInfo
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- CN116375094A CN116375094A CN202310521025.5A CN202310521025A CN116375094A CN 116375094 A CN116375094 A CN 116375094A CN 202310521025 A CN202310521025 A CN 202310521025A CN 116375094 A CN116375094 A CN 116375094A
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- manganese sulfate
- sulfur
- manganese
- manganese dioxide
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- NUJOXMJBOLGQSY-UHFFFAOYSA-N manganese dioxide Chemical compound O=[Mn]=O NUJOXMJBOLGQSY-UHFFFAOYSA-N 0.000 title claims abstract description 68
- 229940099596 manganese sulfate Drugs 0.000 title claims abstract description 58
- 235000007079 manganese sulphate Nutrition 0.000 title claims abstract description 58
- 239000011702 manganese sulphate Substances 0.000 title claims abstract description 58
- SQQMAOCOWKFBNP-UHFFFAOYSA-L manganese(II) sulfate Chemical compound [Mn+2].[O-]S([O-])(=O)=O SQQMAOCOWKFBNP-UHFFFAOYSA-L 0.000 title claims abstract description 58
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 title claims abstract description 35
- 239000011593 sulfur Substances 0.000 title claims abstract description 30
- 229910052717 sulfur Inorganic materials 0.000 title claims abstract description 29
- 238000000034 method Methods 0.000 title claims abstract description 23
- 238000006243 chemical reaction Methods 0.000 claims abstract description 41
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 18
- 239000000706 filtrate Substances 0.000 claims abstract description 18
- 239000007788 liquid Substances 0.000 claims abstract description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 13
- 239000000047 product Substances 0.000 claims abstract description 10
- 239000008367 deionised water Substances 0.000 claims abstract description 9
- 229910021641 deionized water Inorganic materials 0.000 claims abstract description 9
- 238000000926 separation method Methods 0.000 claims abstract description 7
- 238000003756 stirring Methods 0.000 claims description 14
- 238000001704 evaporation Methods 0.000 claims description 13
- 238000002425 crystallisation Methods 0.000 claims description 9
- 230000008025 crystallization Effects 0.000 claims description 9
- 230000008020 evaporation Effects 0.000 claims description 9
- 238000001035 drying Methods 0.000 claims description 8
- 238000001914 filtration Methods 0.000 claims description 7
- 238000010438 heat treatment Methods 0.000 claims description 7
- 230000002378 acidificating effect Effects 0.000 claims description 6
- 238000000227 grinding Methods 0.000 claims description 6
- 239000000843 powder Substances 0.000 claims description 6
- 239000000725 suspension Substances 0.000 claims description 6
- 230000035484 reaction time Effects 0.000 claims description 2
- 239000007787 solid Substances 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 abstract description 8
- 239000002994 raw material Substances 0.000 abstract description 7
- 239000006227 byproduct Substances 0.000 abstract description 2
- 238000005580 one pot reaction Methods 0.000 abstract description 2
- 239000000243 solution Substances 0.000 description 20
- 238000002386 leaching Methods 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 4
- 239000002253 acid Substances 0.000 description 4
- 229910052748 manganese Inorganic materials 0.000 description 4
- 239000011572 manganese Substances 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 230000007547 defect Effects 0.000 description 2
- -1 feeds Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000003723 Smelting Methods 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 239000003929 acidic solution Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000013064 chemical raw material Substances 0.000 description 1
- 239000010779 crude oil Substances 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000003337 fertilizer Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 150000002696 manganese Chemical class 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 231100000956 nontoxicity Toxicity 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 239000000575 pesticide Substances 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- RAHZWNYVWXNFOC-UHFFFAOYSA-N sulfur dioxide Inorganic materials O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
- 238000002424 x-ray crystallography Methods 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G45/00—Compounds of manganese
- C01G45/10—Sulfates
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
Abstract
The invention discloses a method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur, which comprises the following steps: manganese dioxide and sulfur are used as raw materials, deionized water and a certain amount of sulfuric acid solution are added to react in a high-temperature high-pressure reaction kettle, solid-liquid separation is carried out after the reaction is completed, filtrate is evaporated and crystallized, when a small amount of water is left, the filtrate is filtered while the filtrate is hot, and filter residues are collected and dried to obtain a manganese sulfate product. The invention realizes the direct preparation of the manganese sulfate by one-step reaction, has simpler operation steps than the existing manganese sulfate preparation method, does not generate other byproducts, has lower cost and has certain application value in the field of battery-grade manganese sulfate preparation.
Description
Technical Field
The invention belongs to the field of manganese sulfate preparation, and particularly relates to a method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur.
Background
Manganese sulfate is an important manganese salt product and is widely used in the fields of new energy, smelting, materials, chemical fertilizers, feeds, paints, pesticides and the like. About 80% of the world's manganese products are produced using manganese sulfate or from manganese sulfate solutions, which is also a major aspect of manganese sulfate consumption. In recent years, along with the development of new energy battery technology at home and abroad, the production of batteries by using high-purity manganese sulfate as a raw material is increasingly emphasized, and the preparation technology of the high-purity manganese sulfate is also becoming more important.
The existing method for preparing manganese sulfate mainly comprises two methods of reduction roasting acid leaching and manganese ore wet leaching, wherein the reduction roasting acid leaching method has the defects of high roasting temperature, large acid quantity, complex operation and the like; the wet leaching method of manganese ore has the defects of high cost, low manganese conversion rate, large residual slag quantity, environmental pollution and the like. The development of a new preparation method of manganese sulfate is urgent, so the invention provides a method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur.
Manganese dioxide is used as an important chemical raw material, can be used as an oxidant, a rust remover, a catalyst and the like, and has the advantages of wide sources, low cost, easy obtainment, safety, no toxicity and the like; sulfur is one of the main by-products in crude oil production and is considered to be used for producing manganese sulfate as an important element composition in manganese sulfate products. At present, the method for preparing the manganese sulfate by using the reduction roasting acid leaching mode of sulfur and manganese dioxide has been reported, and the method requires high roasting temperature and can generate harmful gas SO 2 And the like, the invention provides a novel method for preparing the manganese sulfate in an acidic solution in one step, which has the advantages of simple operation, low energy consumption, high conversion rate and no sulfur waste gas.
The invention comprises the following steps:
the invention aims to provide a method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur, which solves the problems in the background technology.
The aim of the invention is achieved by the following technical scheme.
A method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur comprises the following specific operations:
(1) Adding purchased manganese dioxide and sulfur into a reaction container, such as a polytetrafluoroethylene high-pressure reaction kettle liner, adding deionized water, dropwise adding sulfuric acid solution into the solution, and stirring while adding to obtain a manganese dioxide and sulfur suspension under an acidic condition;
(2) Heating the reaction container in the step (1), installing the reaction container on a reaction heating sleeve, setting reaction temperature, time, stirring rotation speed and the like, and starting the reaction;
(3) Carrying out solid-liquid separation operation on the solution obtained after the reaction in the step (2), and leaving filtrate;
(4) Transferring the filtrate obtained in the step (3) into a container for evaporation crystallization, and filtering while the filtrate is hot after only a small amount of liquid is left in the evaporation, thus obtaining manganese sulfate filter residues;
(5) And (3) drying the manganese sulfate obtained in the step (4) at 120 ℃ and grinding to obtain a manganese sulfate powder product.
As a preferred embodiment of the invention, the molar ratio of manganese dioxide to sulfur added in the step (1) is 3:1, and the mass ratio of liquid to solid is not less than 13 after deionized water is added; the mass concentration of the sulfuric acid solution is 50-100%.
As a preferred embodiment of the present invention, the manganese dioxide used in the step (1) may be alpha-MnO 2 、β-MnO 2 、γ-MnO 2 、δ-MnO 2 Is sublimed sulfur.
As a preferred embodiment of the invention, the reaction temperature in the step (2) is 50-250 ℃, the reaction time is 1-30h, and the stirring speed is 100-600r/min.
As a preferred embodiment of the present invention, the temperature of the evaporative crystallization in the step (4) is 100-250 ℃.
As a preferred embodiment of the present invention, the drying time in the step (5) is 2-10 hours.
The innovation and beneficial effects of the invention are as follows:
(1) According to the invention, manganese dioxide and sulfur are used as raw materials for the first time, manganese sulfate is prepared under the conditions of high temperature, high pressure and acidity, and the manganese sulfate material is obtained through evaporation crystallization and filtration, so that the one-step reaction is realized to directly prepare manganese sulfate, and the operation steps are simpler than those of the existing manganese sulfate preparation method. Has certain application value in the field of battery-grade manganese sulfate preparation.
(2) The conversion rate of the manganese sulfate prepared by the method can be close to 100%, the raw materials and the cost are saved, the prepared material is purer, and the subsequent purification cost is saved.
Drawings
FIG. 1 is a flow chart of a method of preparing manganese sulfate according to the present invention.
FIG. 2 is an X-ray crystallography chart of a manganese sulfate material prepared in accordance with the present invention.
Detailed Description
For a better understanding of the present invention, the present invention will be described in further detail with reference to the following examples and drawings. It is to be specifically noted that the examples are only for further illustrating the present invention, and the scope of the present invention is not limited thereto.
Referring to FIG. 1, the invention provides a technical scheme that a method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur comprises the following steps: step 1, adding purchased manganese dioxide and sulfur into a liner of a high-pressure reaction kettle, adding deionized water, then dropwise adding sulfuric acid solution into the solution, and stirring while adding to obtain a suspension of manganese dioxide and sulfur under an acidic condition; step 2, installing the inner container of the reaction kettle on a reaction heating sleeve, setting reaction temperature, time, stirring rotation speed and the like, and starting reaction; step 3, carrying out solid-liquid separation operation on the reacted solution, and leaving filtrate; step 4, transferring the obtained filtrate into a beaker for evaporation crystallization, and filtering while the filtrate is hot after evaporating to a small amount of liquid, thereby obtaining manganese sulfate filter residues; and 5, drying the obtained manganese sulfate, and grinding to obtain a manganese sulfate powder product.
Example 1:
2.61g of manganese dioxide and 0.32g of sublimed sulfur raw material are added into a high-pressure reaction kettle liner, 60mL of deionized water is added, sulfuric acid solution is dropwise added into the solution, stirring is carried out while adding to obtain suspension of manganese dioxide and sulfur under an acidic condition, the reaction kettle liner is arranged on a reaction heating sleeve, the reaction temperature is set to 90 ℃, the time is 11h, the stirring rotation speed is 450r/min, and the reaction is started. And (3) carrying out solid-liquid separation operation on the reacted solution, leaving filtrate, transferring the obtained filtrate into a beaker for evaporation crystallization, adding a certain amount of water after evaporating to leave a small amount of liquid, filtering while the solution is hot to obtain manganese sulfate, drying the obtained manganese sulfate, and grinding to obtain a manganese sulfate powder product.
Example 2:
2.61g of manganese dioxide and 0.32g of sublimed sulfur raw material are added into a high-pressure reaction kettle liner, 40mL of deionized water is added, sulfuric acid solution is dropwise added into the solution, stirring is carried out while adding to obtain suspension of manganese dioxide and sulfur under an acidic condition, the reaction kettle liner is arranged on a reaction heating sleeve, the reaction temperature is set to 130 ℃, the time is set to 13h, the stirring speed is set to 350r/min, and the reaction is started. And (3) carrying out solid-liquid separation operation on the reacted solution, leaving filtrate, transferring the obtained filtrate into a beaker for evaporation crystallization, adding a certain amount of water after evaporating to leave a small amount of liquid, filtering while the solution is hot to obtain manganese sulfate, drying the obtained manganese sulfate, and grinding to obtain a manganese sulfate powder product.
Example 3:
2.61g of manganese dioxide and 0.32g of sublimed sulfur raw material are added into a high-pressure reaction kettle liner, 50mL of deionized water is added, sulfuric acid solution is dropwise added into the solution, stirring is carried out while adding to obtain suspension of manganese dioxide and sulfur under an acidic condition, the reaction kettle liner is arranged on a reaction heating sleeve, the reaction temperature is set to be 180 ℃, the time is 18h, the stirring rotation speed is 250r/min, and the reaction is started. And (3) carrying out solid-liquid separation operation on the reacted solution, leaving filtrate, transferring the obtained filtrate into a beaker for evaporation crystallization, adding a certain amount of water after evaporating to leave a small amount of liquid, filtering while the solution is hot to obtain manganese sulfate, drying the obtained manganese sulfate, and grinding to obtain a manganese sulfate powder product.
From the above results, it is evident that the conversion rate of example 3 is 97% or more at the highest, so that example 3 is the best example. FIG. 2 is an X-ray diffraction analysis chart of the manganese sulfate material obtained in the example.
While the fundamental and principal features of the invention and advantages of the invention have been shown and described, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing exemplary embodiments, but may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Furthermore, it should be understood that although the present disclosure describes embodiments, not every embodiment is provided with a separate embodiment, and that this description is provided for clarity only, and that the disclosure is not limited to the embodiments described in detail below, and that the embodiments described in the examples may be combined as appropriate to form other embodiments that will be apparent to those skilled in the art.
Claims (6)
1. A method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur, which is characterized by comprising the following steps:
(1) Adding manganese dioxide and sulfur into a reaction container, adding deionized water, dropwise adding sulfuric acid solution into the solution, and stirring while adding to obtain a suspension of manganese dioxide and sulfur under an acidic condition;
(2) Heating the reaction container in the step (1), stirring, setting reaction parameters, and starting the reaction;
(3) Carrying out solid-liquid separation operation on the solution obtained after the reaction in the step (2), and leaving filtrate;
(4) Transferring the filtrate obtained in the step (3) into a container for evaporation crystallization, and filtering while the filtrate is hot after only a small amount of liquid is left in the evaporation, thus obtaining manganese sulfate filter residues;
(5) And (3) drying the manganese sulfate obtained in the step (4), and grinding to obtain a manganese sulfate powder product.
2. The method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur according to claim 1, wherein the molar ratio of manganese dioxide to sulfur in the step (1) is 3:1, and the mass ratio of liquid to solid is not less than 13 after deionized water is added; the mass concentration of the sulfuric acid solution is 50-100%.
3. The method for preparing high purity manganese sulfate from manganese dioxide and sulfur according to claim 1, wherein in step (1)The manganese dioxide is alpha-MnO 2 、β-MnO 2 、γ-MnO 2 、δ-MnO 2 Is sublimed sulfur.
4. The method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur according to claim 1, wherein the reaction temperature in the step (2) is 50-250 ℃, the reaction time is 1-30h, and the stirring rotation speed is 100-600r/min.
5. The method for preparing high purity manganese sulfate using manganese dioxide and sulfur according to claim 1, wherein the temperature of the evaporative crystallization in step (4) is 100-250 ℃.
6. The method for preparing high-purity manganese sulfate from manganese dioxide and sulfur according to claim 1, wherein the temperature of drying in the step (5) is 120 ℃ and the time is 2-10h.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202310521025.5A CN116375094A (en) | 2023-05-10 | 2023-05-10 | Method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur |
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| CN202310521025.5A CN116375094A (en) | 2023-05-10 | 2023-05-10 | Method for preparing high-purity manganese sulfate by using manganese dioxide and sulfur |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR840001530B1 (en) * | 1983-03-25 | 1984-10-04 | 김수태 | Process for the preparation of manganese sulphates |
| BRPI0804278A2 (en) * | 2008-10-02 | 2010-07-06 | Produquimica Ind E Com S A | manganese sulfate production process from manganese and sulfur biooxide |
| CN106745288A (en) * | 2016-12-14 | 2017-05-31 | 石朝军 | A kind of production method of high-purity manganese sulphate |
| CN115806318A (en) * | 2022-12-13 | 2023-03-17 | 大连融科储能集团股份有限公司 | Production method of manganese sulfate |
-
2023
- 2023-05-10 CN CN202310521025.5A patent/CN116375094A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR840001530B1 (en) * | 1983-03-25 | 1984-10-04 | 김수태 | Process for the preparation of manganese sulphates |
| BRPI0804278A2 (en) * | 2008-10-02 | 2010-07-06 | Produquimica Ind E Com S A | manganese sulfate production process from manganese and sulfur biooxide |
| CN106745288A (en) * | 2016-12-14 | 2017-05-31 | 石朝军 | A kind of production method of high-purity manganese sulphate |
| CN115806318A (en) * | 2022-12-13 | 2023-03-17 | 大连融科储能集团股份有限公司 | Production method of manganese sulfate |
Non-Patent Citations (1)
| Title |
|---|
| 无名: "氧化锰法硫酸锰", 广西化工, vol. 2, pages 26 * |
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