A stirrer and a reaction vessel

Abstract

The application belongs to the technical field of chemical production equipment, and particularly relates to a stirrer and a reaction kettle. The stirrer comprises a stirring shaft arranged in a vertical direction, a driving mechanism connected to the top end of the stirring shaft, and a plurality of radial stirring paddles arranged on the stirring shaft in a vertical direction. All the radial stirring paddles are arranged in parallel on the stirring shaft in a horizontal direction, and the radii of rotation of adjacent radial stirring paddles gradually increase in a direction away from the driving mechanism. The application avoids problems such as time consumption and labor consumption caused by removing excessive sulfamic acid from a reaction solution by filtration, deposition and other methods.

Description

Technical Field

[0001] This invention belongs to the field of chemical production equipment technology, specifically relating to a stirrer and a reaction vessel. Background Technology

[0002] Lithium difluorosulfonylimide exhibits excellent performance in terms of conductivity, low-temperature stability, high-temperature stability, electrochemical stability, and compatibility, and it is virtually free of side reactions. Furthermore, lithium difluorosulfonylimide can suppress swelling, making it an ideal electrolyte for next-generation lithium-ion batteries.

[0003] Currently, the main methods for preparing lithium difluorosulfonylimide are as follows: (1) First, synthesize the intermediate dichlorosulfonylimide (HClSI), and then use dichlorosulfonylimide (HClSI) as raw material to prepare lithium difluorosulfonylimide. However, when preparing lithium difluorosulfonylimide using this method, a large amount of corrosive hydrogen fluoride gas will be generated during the reaction process, and the product contains impurities such as hydrogen fluoride and lithium fluoride, which are difficult to separate. In addition, hydrogen fluoride remains in the electrolyte with lithium difluorosulfonylimide, which will affect the performance of lithium-ion batteries. (2) Dichlorosulfonylimide (HClSI) reacts with ammonium fluoride to synthesize difluorosulfonylimide amine salt, and then difluorosulfonylimide amine salt reacts with lithium hydroxide through a cation exchange reaction to prepare lithium difluorosulfonylimide. However, when preparing lithium difluorosulfonylimide using this method, the cation exchange reaction is difficult to be complete, resulting in high impurity content in the prepared lithium difluorosulfonylimide. (3) Difluorosulfonylimide lithium is prepared by exchange reaction of potassium bisfluorosulfonylimide (KFSI) and lithium perchlorate. However, when preparing bisfluorosulfonylimide lithium by this method, a large amount of potassium ions will remain in the prepared bisfluorosulfonylimide lithium.

[0004] The first method is the most commonly used, and the synthesis of dichlorosulfonylimide (HClSI) generally uses sulfonamide, thionyl chloride, and chlorosulfonic acid as raw materials. Currently, the reaction vessels used for chlorination reactions in industrial production are all mixed-flow reactors, and the yield and purity of dichlorosulfonylimide (HClSI) synthesized using a mixed-flow reactor are not good. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a stirrer and a reaction vessel to solve the technical problem that the reaction vessels used for chlorination reactions in industrial production in the prior art are all fully mixed flow reaction vessels, and the yield and purity of bischlorosulfonylimide (HClSI) synthesized using a fully mixed flow reaction vessel are poor.

[0006] In some embodiments, this application provides a stirrer, the stirrer including a stirring shaft arranged in a vertical direction, a drive mechanism connected to the top end of the stirring shaft, and a plurality of radial stirring blades arranged in a vertical direction on the stirring shaft, all of the radial stirring blades being arranged parallel to each other in a horizontal direction on the stirring shaft, and the rotation radius of adjacent radial stirring blades gradually increasing in the direction away from the drive mechanism.

[0007] In some embodiments, the rotational radii of adjacent radial stirring blades along the direction away from the drive mechanism gradually increase in an arithmetic sequence.

[0008] In some embodiments, the radial stirring blades located at the upper part of the stirrer are variable diameter stirring blades.

[0009] In some embodiments, the radius of rotation of the radial stirring blade is determined by the following steps:

[0010] The historical target product concentrations at several heights along the vertical direction inside the stirrer are obtained, and the several positions correspond to the heights of each radial stirring blade.

[0011] Based on the historical target product concentration, determine the rotation radius of the radial stirring blades at the corresponding height.

[0012] In some embodiments, determining the radius of rotation of the radial stirring blades at a corresponding height includes:

[0013] Based on the historical target product concentration, the outer diameter of the preset top radial stirring blade, and the outer diameter of the preset bottom radial stirring blade, the rotation radius of the radial stirring blade at the corresponding height is determined, wherein the outer diameter of the preset top radial stirring blade is greater than the outer diameter of the preset bottom radial stirring blade.

[0014] In some embodiments, the rotation radius of the radial stirring blade at a corresponding height is determined according to the historical target product concentration, the outer diameter of rotation of the topmost radial stirring blade, and the bottommost radial stirring blade, using the following formula:

[0015] ;

[0016] Where Ci represents the historical target product concentration at each location; C h The historical target product concentration at the very top; C l D represents the historical target product concentration at the lowest position; D represents the radial outer diameter of the stirring blades at the corresponding height at each position; D l D is the preset outer diameter of the radial stirring blade at the bottom; h This is the preset outer diameter of the radial stirring blade at the very top.

[0017] In some embodiments, the stirring shaft is further provided with a fully mixed flow blade, which is located below the lowest radial stirring blade.

[0018] In some embodiments, the fully mixed-flow blade is at least one of the following: anchor blade, frame blade, helical blade, ribbon blade, propeller blade, fan blade, and folding blade blade.

[0019] In some embodiments, the fully mixed-flow blades are anchor blades.

[0020] In some embodiments, this application also provides a reaction vessel, which includes a stirrer as described above.

[0021] The beneficial effects of this invention are:

[0022] This invention arranges several radial stirring blades vertically on a stirring shaft, with all radial stirring blades arranged horizontally parallel to the stirring shaft. The rotation radius of adjacent radial stirring blades gradually increases in the direction away from the drive mechanism, making the rotation radius of the top radial stirring blades smaller. This reduces the stirring effect and facilitates the deposition of unreacted raw materials (e.g., aminosulfonic acid) at the bottom. Under low linear velocity and small stirring range conditions, the unreacted raw materials (e.g., aminosulfonic acid) are deposited, and the reaction products (e.g., dichlorosulfonylimide) floating on the liquid surface are allowed to overflow into the next process. This achieves the separation of unreacted raw materials and reaction products, avoiding the time-consuming and labor-intensive problems caused by removing excess aminosulfonic acid from the post-reaction solution through filtration, sedimentation, etc.

[0023] The mixing device of this application enables continuous production and improves production efficiency. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the stirrer in Comparative Example 1;

[0025] Figure 2 This is a schematic diagram of the stirrer in Example 1;

[0026] Figure 3 This is a schematic diagram of the stirrer in Example 3;

[0027] Figure 4 This is a schematic diagram of the stirrer in Example 4. Detailed Implementation

[0028] The present invention will be further illustrated by specific examples below. However, it should be noted that the specific material ratios, process conditions and results described in the embodiments of the present invention are only for illustrating the present invention and cannot be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

[0029] This application provides a stirrer, which includes a stirring shaft arranged in a vertical direction, and a plurality of radial stirring blades arranged in the vertical direction on the stirring shaft. All radial stirring blades are arranged parallel to each other in the horizontal direction on the stirring shaft, and the rotation radius of adjacent radial stirring blades gradually increases in the direction away from the drive mechanism.

[0030] In some embodiments, the rotation radius of adjacent radial stirring blades along the direction away from the drive mechanism gradually increases in an arithmetic sequence.

[0031] In some embodiments, the radial stirring blades located at the top of the stirrer are variable diameter stirring blades.

[0032] In some embodiments, the radius of rotation of the radial stirring blades is determined by the following steps:

[0033] The historical target product concentrations at several heights along the vertical direction inside the stirrer are obtained, and these positions correspond to the heights of each radial stirring blade.

[0034] The rotation radius of the radial stirring blade at the corresponding height is determined according to the historical target product concentration, the outer diameter of the rotation of the top radial stirring blade, and the bottom radial stirring blade, with the outer diameter of the rotation of the top radial stirring blade set to be greater than the outer diameter of the rotation of the bottom radial stirring blade.

[0035] ;

[0036] Where Ci represents the historical target product concentration at each location; C h The historical target product concentration at the very top; C l D represents the historical target product concentration at the lowest position; D represents the radial outer diameter of the stirring blades at the corresponding height at each position; D l D is the preset outer diameter of the radial stirring blade at the bottom; h This is the preset outer diameter of the radial stirring blade at the very top.

[0037] In some embodiments, the stirring shaft is further provided with a fully mixed flow blade, which is located below the lowest radial stirring blade. The fully mixed flow blade is at least one of the following: anchor blade, frame blade, spiral blade, ribbon blade, propeller blade, fan blade, and folding blade blade.

[0038] In some embodiments, the fully mixed-flow blades are anchor blades.

[0039] In some embodiments, this application also provides a reaction vessel including the stirrer described above.

[0040] It should be noted that all directional indicators (such as up, down, top, bottom) in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0041] Furthermore, the technical solutions of the various embodiments can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0042] The present invention will be described in detail below through specific examples and embodiments. It should also be understood that the following embodiments are only for specific illustration of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above description of the present invention are within the scope of protection of the present invention. The specific process parameters, etc., in the following examples are merely examples within a suitable range; that is, those skilled in the art can make appropriate selections within the appropriate range based on the description herein, and are not intended to be limited to the specific values ​​in the examples below.

[0043] Comparative Example 1

[0044] Please see Figure 1 , Figure 1 This is a schematic diagram of the stirrer used in this comparative example.

[0045] like Figure 1 As shown, the stirrer in this embodiment includes a stirring shaft 1 arranged in a vertical direction and a drive mechanism 2.

[0046] Please continue reading. Figure 1 The top end of the stirring shaft 1 is connected to the drive mechanism 2. Several radial stirring blades 11 with identical rotation radii are arranged vertically on the stirring shaft 1, and all radial stirring blades 11 are arranged parallel to each other on the stirring shaft 1 in the horizontal direction. The drive mechanism 2 can be a motor, etc. Motors are existing technology and will not be described in detail here.

[0047] Example 1

[0048] Please see Figure 1 , Figure 1 This is a schematic diagram of the stirrer in this embodiment.

[0049] like Figure 1 As shown, the stirrer in this embodiment includes a stirring shaft 1 arranged in a vertical direction and a drive mechanism 2.

[0050] Please continue reading. Figure 1 The top end of the stirring shaft 1 is connected to the drive mechanism 2. Several radial stirring blades 11 are vertically arranged on the stirring shaft 1, and all radial stirring blades 11 are arranged horizontally parallel to each other on the stirring shaft 1. The rotation radius of adjacent radial stirring blades 11 gradually increases in the direction away from the drive mechanism 2; specifically, the rotation radius of adjacent radial stirring blades 11 gradually increases in an arithmetic progression in the direction away from the drive mechanism 2. The drive mechanism 2 can be a motor, etc., which is existing technology and will not be described in detail here.

[0051] The difference between this embodiment and Comparative Example 1 is that the rotation radius of adjacent radial stirring blades 11 gradually increases along the direction away from the drive mechanism 2.

[0052] The principle of the stirrer in this embodiment is as follows: the reactants continuously enter the reactor from the bottom. The radial stirring blades 11 located at the bottom have a large rotation radius, giving them a larger stirring range and linear velocity. This allows for thorough stirring of the reactants initially entering the reactor, primarily serving to stir and thus ensure a complete reaction. The reaction products (e.g., dichlorosulfonylimide) float on the surface due to their lower density. (The molar ratio of chlorosulfonic acid to thionyl chloride is controlled at 1:5, and the molar ratio of chlorosulfonic acid to aminosulfonic acid is 1:1.5, meaning that chlorosulfonic acid accounts for the smallest proportion of the three, while thionyl chloride and aminosulfonic acid are in excess. This ensures that chlorosulfonic acid participates in the reaction as much as possible, and the unreacted thionyl chloride can be further processed through subsequent flash evaporation and heating.) Separation is achieved because the density of aminosulfonic acid (2.126 g / cm³) is greater than that of dichlorosulfonamide (2.049 g / cm³), thus aminosulfonic acid will deposit at the bottom of the reactor. The radial stirring blade 11 at the top has a smaller rotation radius, which reduces the stirring effect and facilitates the deposition of unreacted raw materials (such as aminosulfonic acid) at the bottom. This allows the unreacted raw materials (such as aminosulfonic acid) to deposit under low linear velocity and small stirring range conditions, while the reaction products (such as dichlorosulfonamide) floating on the liquid surface are allowed to enter the next process through overflow. This achieves the separation of unreacted raw materials and reaction products, avoiding the time-consuming and labor-intensive problems caused by removing excess aminosulfonic acid from the post-reaction solution through filtration, sedimentation, etc.

[0053] The stirrer in this embodiment can be used as a stirring device in a reactor for preparing dichlorosulfonylimide by chlorination of chlorosulfonic acid, thionyl chloride and aminosulfonic acid, or as a stirring device in a reactor for preparing difluorosulfonylimide by fluorination of dichlorosulfonylimide and hydrogen fluoride.

[0054] Example 2

[0055] The difference between this embodiment and Embodiment 1 is that the radial stirring blade 11 located at the top of the stirrer is a variable-diameter stirring blade. The variable-diameter stirring blade adopts the specific structure of CN2481424Y. For example, a rotating disk is added at the corresponding position of the radial stirring blade 11 at the top of the stirring shaft 1. The rotating disk has several circumferentially evenly arranged guide slots and connecting slots for adjusting the diameter. The radial stirring blade 11 is fastened to the rotating disk by bolts. When a change in diameter is required, the bolts are loosened, and the radial stirring blade 11 is moved radially along the guide slot 3 until the desired diameter is reached, after which the bolts are tightened.

[0056] Example 3

[0057] Please see Figure 3 , Figure 3 This is a schematic diagram of the stirrer in this embodiment.

[0058] like Figure 3 As shown, the difference between this embodiment and Embodiment 1 is that the rotation radius of adjacent radial stirring blades 11 along the direction away from the drive mechanism 2 does not gradually increase in an arithmetic sequence, but is determined by the following steps:

[0059] The historical target product concentrations at several heights along the vertical direction inside the stirrer are obtained, and these positions correspond to the heights of each radial stirring blade.

[0060] The rotation radius of the radial stirring blades at the corresponding height is determined according to the historical target product concentration, the outer diameter of the rotation of the topmost radial stirring blade, and the outer diameter of the bottommost radial stirring blade, using the following formula. The outer diameter of the rotation of the topmost radial stirring blade is preset to be larger than the outer diameter of the rotation of the bottommost radial stirring blade.

[0061] ;

[0062] Where Ci represents the historical target product concentration at each location; C h The historical target product concentration at the very top; C l D represents the historical target product concentration at the lowest position; D represents the radial outer diameter of the stirring blades at the corresponding height at each position; D l D is the preset outer diameter of the radial stirring blade at the bottom; h This is the preset outer diameter of the topmost radial stirring blade. It should be noted that the historical target product concentration refers to the concentration of the target product difluorosulfonylimide at the corresponding height of each radial stirring blade in a reactor using the stirrer of Comparative Example 1, for example, in the preparation of difluorosulfonylimide from dichlorosulfonylimide and hydrogen fluoride.

[0063] Example 4

[0064] Please see Figure 4 , Figure 4 This is a schematic diagram of the stirrer in this embodiment.

[0065] like Figure 4 As shown, the difference between this embodiment and Embodiment 1 is that a fully mixed-flow impeller 12 is also provided on the stirring shaft 1, and the fully mixed-flow impeller 12 is located below the lowest radial stirring impeller 11. The fully mixed-flow impeller 12 is an anchor-type axial stirring impeller.

[0066] Specifically, this embodiment adds a fully mixed flow impeller 12 below the radial stirring impeller 11 at the bottom, which can more fully stir the reaction raw materials initially entering the reactor, thereby improving reaction efficiency and product yield.

[0067] test

[0068] Dichlorosulfonylimide was prepared by fluorination reaction using dichlorosulfonylimide and hydrogen fluoride as raw materials. The reaction vessels were equipped with stirrers as in Comparative Example 1, Example 3, and Example 4, respectively. The reaction temperature was 110℃, and the reaction pressure was 1.35 MPa. The outer diameter of the stirring blades of the stirrers is shown in Table 1. After 1 hour, the concentration of dichlorosulfonylimide at the corresponding height of each stirring blade in the reaction vessel was measured. The detection method was as follows: after the system stabilized, the machine was stopped, and samples were quickly taken from the reaction liquid at different heights. The concentration of dichlorosulfonylimide in the samples at each location was detected according to "YS / T 1302-2019 Power Battery Electrolyte Dichlorosulfonylimide Lithium Salt". The results are shown in Table 2.

[0069] Table 1. Rotational outer diameter (d) of the impeller blades of different agitators

[0070]

[0071] Table 2 Concentration at various positions of the impeller blades of different agitators

[0072]

[0073] As shown in Table 2, the product concentration of Example 1 can be increased to 78.3% compared with Comparative Example 1. This result indicates that the rotation radius of adjacent radial stirring blades gradually increases in an arithmetic sequence in the direction away from the drive mechanism, which can improve the product yield and purity.

[0074] As shown in Table 2, the product concentration in Example 3 can be increased to 79.5% compared to Example 1. This result indicates that by setting the rotation radius of the radial stirring blade 11 to vary with the concentration of the reaction product, the product yield and purity can be further improved.

[0075] As shown in Table 2, compared with Example 3, the initial bottom reaction rate in Example 4 was significantly increased, resulting in an overall increase in reaction rate. This result indicates that by adding a fully mixed-flow impeller located below the radial stirring impeller 11 at the bottom, production efficiency can be significantly improved, thereby increasing reaction efficiency and product yield.

[0076] In some embodiments, this application also provides a reaction vessel, which includes the stirrer described above. In this application, the types of reaction vessels may include, for example, a vertical plug flow reaction vessel. Vertical plug flow reaction vessels are prior art and will not be described further here.

[0077] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A stirrer, characterized in that, The stirrer includes a stirring shaft arranged in a vertical direction, a drive mechanism connected to the top of the stirring shaft, and a plurality of radial stirring blades arranged in a vertical direction on the stirring shaft. All radial stirring blades are arranged parallel to each other in a horizontal direction on the stirring shaft, and the rotation radius of adjacent radial stirring blades gradually increases in the direction away from the drive mechanism. The rotation radius of the radial stirring blade is determined by the following steps: The historical target product concentrations at several heights along the vertical direction inside the stirrer are obtained, and the several heights correspond to the heights of each radial stirring blade. Based on the historical target product concentration, determine the rotation radius of the radial stirring blades at the corresponding height.

2. The stirrer as described in claim 1, characterized in that, The radial stirring blades located at the top of the stirrer are variable diameter stirring blades.

3. The stirrer as described in claim 1, characterized in that, Determine the radius of rotation of the radial stirring blades at the corresponding height, including: Based on the historical target product concentration, the outer diameter of the preset top radial stirring blade, and the outer diameter of the preset bottom radial stirring blade, the rotation radius of the radial stirring blade at the corresponding height is determined, wherein the outer diameter of the preset top radial stirring blade is greater than the outer diameter of the preset bottom radial stirring blade.

4. The stirrer as described in claim 3, characterized in that, The rotation radius of the radial agitator blades at the corresponding height is determined using the following formula, based on the historical target product concentration, the outer diameter of the rotation of the topmost radial agitator blade, and the bottommost radial agitator blade: ； Where Ci represents the historical target product concentration at each location; C h The historical target product concentration at the very top; C l D represents the historical target product concentration at the lowest position; D represents the radial outer diameter of the stirring blades at the corresponding height at each position; D l D is the preset outer diameter of the radial stirring blade at the bottom; h This is the preset outer diameter of the radial stirring blade at the very top.

5. The stirrer as described in claim 1, characterized in that, The stirring shaft is also equipped with a fully mixed flow blade, which is located below the bottommost radial stirring blade.

6. The stirrer as described in claim 5, characterized in that, The fully mixed-flow blade is at least one of the following: anchor blade, frame blade, spiral blade, ribbon blade, propeller blade, fan blade, and folding blade blade.

7. The stirrer as described in claim 6, characterized in that, The fully mixed-flow blades are anchor-type blades.

8. A reaction vessel, characterized in that, The reactor includes a stirrer as described in any one of claims 1-7.

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