Method for synthesizing high-purity or battery-grade manganous-manganic oxide

Abstract

The invention discloses a method for synthesizing high-purity or battery-grade manganous-manganic oxide, and belongs to the technical field of chemical synthesis. The invention relates to a method for synthesizing high-purity or battery-grade manganous-manganic oxide. The method comprises the following steps: S1, preparing a manganese hydroxide slurry suspension by using high-purity manganese hydroxide as a raw material and pure water; s2, adding ammonium salt into the reaction device as a catalyst; s3, introducing hot air at 25-90 DEG C into the reaction device, and reacting to obtain solid manganous-manganic oxide; and S4, filtering and drying the solid manganous-manganic oxide to obtain a high-purity manganous-manganic oxide product, and recycling filtrate to prepare slurry.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical synthesis, and more specifically, relates to a method for synthesizing high-purity or battery-grade manganese tetraoxide. Background Art

[0002] Manganese manganese tetroxide is a common metal oxide with the molecular formula Mn3O4. It is a black tetragonal crystal. Manganese manganese tetroxide is mainly used in the electronics industry and is the raw material for producing soft ferrites. In addition, it can also be used to prepare stable, high-capacity, supercapacitors, and even improve the effectiveness and safety of batteries. Manganese manganese tetroxide can also be used as a pigment for certain paints or coatings in the processing field. It has better corrosion resistance. Manganese manganese tetroxide can also be used in the manufacture of optical glass and low-temperature thermistors.

[0003] The existing methods for synthesizing manganese tetraoxide mainly include the metal manganese method and the manganese carbonate method. The metal manganese method uses electrolytic manganese metal flakes as raw materials, crushes and slurries the electrolytic manganese metal flakes to obtain a metal manganese powder suspension, which is then reacted with an ammonium salt aqueous solution. Air is introduced into the reaction process for 12-24 hours, and the reaction temperature is 40-80°C. After the reaction, the product is washed and dried to obtain the manganese tetraoxide product. In the reaction process of this method, a large amount of hydrogen will escape, which has a high risk factor, and the degree of crushing of the electrolytic manganese metal in the production process has a certain impact on the product quality. Therefore, the crushing equipment has high requirements and the cost is high. At the same time, the manganese tetraoxide produced by this scheme cannot meet the battery grade purity. The manganese carbonate method is to heat manganese carbonate to 300-400°C to decompose it into MnO and carbon dioxide, and then continue to heat it to 700°C to convert MnO and carbon dioxide into manganese tetraoxide. This method has simple process conditions and is easy to realize industrial production, but the production cost is high, the equipment is complex and the energy consumption is high, the carbon monoxide produced needs to be processed again, and the manganese tetraoxide produced by this scheme cannot meet the battery grade purity.

[0004] Therefore, we need a synthesis method with convenient processing technology and high purity of manganese tetraoxide product. Summary of the invention

[0005] The object of the present invention is to provide a method for synthesizing high-purity or battery-grade manganese tetraoxide. The method has convenient processing technology, and the processed manganese tetraoxide product has high purity and impurity content at the ppm level, which can meet the market demand of the battery industry.

[0006] To achieve the above object, the present invention provides the following technical solutions: A method for synthesizing high-purity or battery-grade manganese tetraoxide of the present invention comprises the following steps: S1. Using high-purity manganese hydroxide as a raw material, a manganese hydroxide slurry suspension is prepared with pure water in a reaction device; S2. adding an ammonium salt to the reaction apparatus as a catalyst; S3. Hot air at 25-90 ° C is introduced into the reaction device to obtain solid manganese tetraoxide; S4. The solid manganese tetraoxide is filtered and dried to obtain a high-purity manganese tetraoxide product, and the filtrate is recycled to prepare the slurry.

[0007] The reaction equation of step S3 is: 6Mn(OH)2+O2=2Mn3O4+6H2O.

[0008] As a further improvement of the present invention, the ammonium salt in step S2 is ammonium chloride or ammonium sulfate.

[0009] As a further improvement of the present invention, the concentration of ammonium chloride or ammonium sulfate in the liquid phase system in the reaction device is 5-30%.

[0010] As a further improvement of the present invention, the reaction time in step S3 is 4-24 hours.

[0011] As a further improvement of the present invention, the reaction device includes a reactor, a stirring motor, a ventilation device and a supporting device; the supporting device is detachably mounted on the upper part of the reactor, located at the top cover arranged on the top of the reactor; a feed port and a feeding port are respectively arranged on the top cover, the feed port is used to convey the hot air transmitted by the ventilation device, and the feeding port is used to add materials during the reaction process or to recycle the filtrate during the secondary reaction; the stirring motor is detachably mounted inside the supporting device, and is used to stir the manganese hydroxide slurry suspension so that the manganese hydroxide remains in a suspended state; the ventilation device is connected to the inside of the reactor, and is used to convey hot air to the reactor; a discharge port is provided at the bottom of the reactor, and is used to discharge the solid manganese tetraoxide obtained by the reaction.

[0012] As a further improvement of the present invention, the ventilation device includes a heat converter, a connecting pipe, a sealing gasket, a ventilation straight pipe and a plurality of stirring air pipes. The sealing gasket is detachably mounted on the supporting device, and the top is pressed by the gravity of the stirring motor to prevent hot air from leaking during transmission and affecting the reaction efficiency; the connecting pipe is detachably mounted inside the supporting device, and has three openings, namely, a top opening, a bottom opening and a side opening; the top opening of the connecting pipe abuts against the bottom of the sealing gasket to prevent hot air from leaking; the bottom opening is detachably mounted at the feed port; the side opening is detachably connected to the heat converter to receive the hot air transported by the heat converter; the ventilation straight pipe is rotatably connected to the inner wall of the connecting pipe, and the top of the ventilation straight pipe is detachably connected to the output end of the stirring motor; ventilation holes are provided on both sides of the stirring air pipe, and the center is fixedly mounted on the lower section of the ventilation straight pipe to transport the hot air output by the heat converter to the inside of the reactor.

[0013] As a further improvement of the present invention, the plurality of stirring air pipes are fixedly installed at different heights below the ventilation straight pipe to prevent the hot air transported to the bottom of the reactor from being cooled by the manganese hydroxide slurry suspension, resulting in different temperatures at different liquid levels of the suspension, thereby affecting the reaction rate.

[0014] As a further improvement of the present invention, a plurality of ventilation grooves are opened on the top of the ventilation straight pipe, and the positions of the ventilation grooves correspond to the side openings of the connecting pipe, which are used to transfer the hot air transported to the connecting pipe to the inside of the ventilation straight pipe through the ventilation grooves.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: a method for synthesizing high-purity or battery-grade manganese tetraoxide of the present invention has a short process and a simple flow, and no new impurity elements are introduced in the production process of synthesizing manganese tetraoxide with high-purity manganese hydroxide, thereby improving the purity of the manganese tetraoxide product and meeting the battery-grade purity requirements, and at the same time, ammonium sulfate is not consumed as a catalyst during the production process, so that the method can react and synthesize continuously, saving production costs; by using a manganese hydroxide slurry suspension to react with hot air, the hot air can fully react with the manganese hydroxide, thereby improving the synthesis efficiency; by arranging a ventilation device driven by a stirring motor, the contact area between the hot air and the manganese hydroxide slurry suspension during the stirring process is increased, thereby improving the reaction speed, and at the same time, stirring also allows the manganese hydroxide to remain in a suspended state. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a process flow chart of the present invention; Figure 2 It is a schematic diagram of the structure of the reaction device of the present invention; Figure 3 It is a schematic diagram of the structure of the ventilation device of the present invention; Figure 4 It is an exploded view of the cross-sectional structure of the ventilation device of the present invention.

[0017] Description of the numbers in the figure: 1 reaction kettle, 11 top cover, 111 feed port, 112 feeding port, 12 discharge port, 2 stirring motor, 3 ventilation device, 31 heat converter, 32 connecting pipe, 321 top port, 322 bottom port, 323 side port, 33 sealing gasket, 34 ventilation straight pipe, 341 ventilation groove, 35 stirring air pipe, 4 supporting device. DETAILED DESCRIPTION

[0018] Specific embodiment 1: Please refer to Figure 1 A method for synthesizing high-purity or battery-grade manganese tetraoxide comprises the following steps: S1. Using high-purity manganese hydroxide as a raw material, a manganese hydroxide slurry suspension is prepared with pure water in a reaction device; S2. adding an ammonium salt to the reaction apparatus as a catalyst; S3. Hot air at 25-90 ° C is introduced into the reaction device to obtain solid manganese tetraoxide; S4. The solid manganese tetraoxide is filtered and dried to obtain a high-purity manganese tetraoxide product, and the filtrate is recycled to prepare the slurry.

[0019] The reaction equation of step S3 is: 6Mn(OH)2+O2=2Mn3O4+6H2O.

[0020] Specifically, the ammonium salt in step S2 is ammonium chloride or ammonium sulfate, and the ammonium salt can be dissociated into ammonium ions (NH4 + ) and the corresponding anion (Cl - or SO4 2- ). These ions can serve as active centers for reactions and promote interactions between reactants.

[0021] Specifically, the concentration of ammonium chloride or ammonium sulfate in the liquid phase system of the reaction device is 5-30%.

[0022] Specifically, the reaction time of step S3 is 4-24 hours.

[0023] Specifically, Figure 2 The reaction device shown includes a reactor 1, a stirring motor 2, a ventilation device 3 and a supporting device 4; the supporting device 4 is detachably installed on the upper part of the reactor 1, and is located at a top cover 11 arranged on the top of the reactor 1; a feed port 111 and a feeding port 112 are respectively provided on the top cover 11, the feed port 111 is used to convey the hot air transmitted by the ventilation device 3, and the feeding port 112 is used to add materials during the reaction process or to recycle the filtrate during the secondary reaction; the stirring motor 2 is detachably installed inside the supporting device 4, and is used to stir the manganese hydroxide slurry suspension so that the manganese hydroxide remains in a suspended state; the ventilation device 3 is connected to the inside of the reactor 1, and is used to convey hot air to the reactor 1; a discharge port 12 is provided at the bottom of the reactor 1, and is used to discharge the solid manganese tetraoxide obtained by the reaction.

[0024] Specifically, Figure 3The ventilation device 3 shown includes a heat converter 31, a connecting pipe 32, a sealing pad 33, a ventilation straight pipe 34 and a plurality of stirring air pipes 35. The sealing pad 33 is detachably mounted on the supporting device 4, and the top is pressed by the gravity of the stirring motor 2 to prevent the hot air from leaking during the transmission process and affecting the reaction efficiency; the connecting pipe 32 is detachably mounted inside the supporting device 4, and has three openings: a top opening 321, a bottom opening 322 and a side opening 323; the top opening 321 of the connecting pipe 32 abuts against the bottom of the sealing pad 33 to prevent the hot air from leaking; the bottom opening 322 is detachably mounted at the feed port 111 to detachably fix the connecting pipe 32 on the top of the reactor 1; The side port 323 is detachably connected to the heat converter 31 for receiving the hot air delivered by the heat converter 31; the ventilation straight pipe 34 is rotatably connected to the inner wall of the connecting pipe 32, and the top of the ventilation straight pipe 34 is detachably connected to the output end of the stirring motor 2, and the ventilation straight pipe 34 is driven to rotate by the stirring motor 2; ventilation holes are provided on both sides of the stirring air pipe 35, and the center is fixedly installed at the lower section of the ventilation straight pipe 34, and rotates with the rotation of the ventilation straight pipe 34, while the hot air output by the heat converter 31 is delivered to the inside of the reactor 1 through the ventilation holes, the manganese hydroxide suspension is stirred to keep it in a suspended state, to ensure that the hot air can fully react with the manganese hydroxide suspension, and to increase the reaction rate.

[0025] Specifically, a plurality of stirring air pipes 35 are respectively fixedly installed at different heights below the ventilation straight pipe 34, so as to prevent the hot air transported to the bottom of the reactor 1 from being cooled by the manganese hydroxide slurry suspension, resulting in different temperatures at different liquid levels of the suspension, thereby affecting the reaction speed; stirring air pipes 35 are arranged at different heights to introduce hot air to ensure a more uniform temperature distribution, so that the reaction system is more evenly distributed, and the reaction time is avoided to be prolonged due to inconsistent reaction speeds of the upper and lower layers in the reactor 1.

[0026] Specifically, Figure 4 The top of the ventilation straight pipe 34 is provided with a plurality of ventilation grooves 341, which correspond to the side openings 323 of the connecting pipe 32, and are used to transfer the hot air delivered to the connecting pipe 32 to the inside of the ventilation straight pipe 34 through the ventilation grooves 341 while the ventilation straight pipe 34 rotates.

[0027] During use, high-purity manganese hydroxide is prepared into a manganese hydroxide slurry suspension with pure water, added into the reactor 1, and ammonium chloride or ammonium sulfate is added as a catalyst simultaneously; the stirring motor 2 is turned on to drive the ventilation straight pipe 34 to drive the stirring air pipe 35 to rotate and stir the liquid phase medium to make it evenly distributed; the heat converter 31 is turned on to convey hot air with a temperature of 25-90° C., and the hot air is sequentially conveyed to the reactor 1 through the side port 323 of the connecting pipe 32, the ventilation groove 341 of the ventilation straight pipe 34 and the ventilation hole of the stirring air pipe 35, so that the hot air reacts evenly with the manganese hydroxide suspension at different liquid levels, the reaction product is discharged through the discharge port 12, and a high-purity manganese tetraoxide product is obtained by filtering and drying, and the obtained filtrate is an aqueous solution containing ammonium chloride or ammonium sulfate; the filtrate is recycled to prepare manganese hydroxide slurry and added to the reactor 1 through the feeding port 112 to complete the sustainable reaction.

[0028] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for synthesizing high-purity or battery-grade manganese tetraoxide, characterized in that: The following steps are involved: S1. Using high-purity manganese hydroxide as a raw material, a manganese hydroxide slurry suspension is prepared with pure water in a reaction device; S2. adding an ammonium salt to the reaction apparatus as a catalyst; S3. Hot air at 25-90 ° C is introduced into the reaction device to obtain solid manganese tetraoxide; S4. The solid manganese tetraoxide is filtered and dried to obtain a high-purity manganese tetraoxide product, and the filtrate is recycled to prepare the slurry.

2. A method for synthesizing high-purity or battery-grade manganese tetraoxide according to claim 1, characterized in that: The ammonium salt in step S2 is ammonium chloride or ammonium sulfate.

3. A method for synthesizing high-purity or battery-grade manganese tetraoxide according to claim 2, characterized in that: The concentration of the ammonium chloride or ammonium sulfate solution in the liquid phase system in the reaction device is 5-30%.

4. A method for synthesizing high-purity or battery-grade manganese tetraoxide according to claim 1, characterized in that: The reaction time of step S3 is 4-24h.

5. A method for synthesizing high-purity or battery-grade manganese tetraoxide according to claim 1, characterized in that: The reaction device comprises a reaction kettle (1), a stirring motor (2), a ventilation device (3) and a support device (4); the support device (4) is detachably mounted on the upper part of the reaction kettle (1) and is located at a top cover (11) arranged on the top of the reaction kettle (1); a feed port (111) and a feeding port (112) are respectively arranged on the top cover (11); the feed port (111) is used to transport hot air transmitted by the ventilation device (3), and the feeding port (112) is used to add materials during the reaction process; the stirring motor (2) is detachably mounted inside the support device (4); the ventilation device (3) is connected to the inside of the reaction kettle (1); and a discharge port (12) is arranged at the bottom of the reaction kettle (1) for discharging solid manganese tetraoxide obtained by the reaction.

6. A method for synthesizing high-purity or battery-grade manganese tetraoxide according to claim 5, characterized in that: The ventilation device (3) comprises a heat converter (31), a connecting pipe (32), a sealing gasket (33), a ventilation straight pipe (34) and a plurality of stirring air pipes (35); the sealing gasket (33) is detachably mounted on the supporting device (4), and the top is pressed by the gravity of the stirring motor (2); the connecting pipe (32) is detachably mounted inside the supporting device (4), and has three openings, namely, a top opening (321), a bottom opening (322) and a side opening (323); the top opening (321) of the connecting pipe (32) contacts the sealing gasket (33). At the bottom of the pad (33), the bottom opening (322) is detachably mounted at the feed opening (111), and the side opening (323) is detachably connected to the heat converter (31); the ventilation straight pipe (34) is rotatably connected to the inner wall of the connecting pipe (32), and the top of the ventilation straight pipe (34) is detachably connected to the output end of the stirring motor (2); ventilation holes are opened on both sides of the stirring air pipe (35), and the center is fixedly mounted on the lower section of the ventilation straight pipe (34) for conveying the hot air output by the heat converter (31) to the interior of the reaction kettle (1).

7. A method for synthesizing high-purity or battery-grade manganese tetraoxide according to claim 6, characterized in that: The plurality of stirring air pipes (35) are respectively fixedly installed at different heights below the ventilation straight pipe (34) to reduce the loss of hot air temperature.

8. A method for synthesizing high-purity or battery-grade manganese tetraoxide according to claim 6, characterized in that: The top of the ventilation straight pipe (34) is provided with a plurality of ventilation grooves (341), the positions of the ventilation grooves (341) corresponding to the side openings (323) of the connecting pipe (32), and are used to transfer hot air delivered to the connecting pipe (32) to the inside of the ventilation straight pipe (34) through the ventilation grooves (341).

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