A method and system for preparing t-butylacrylamide sulfonic acid

Abstract

The application discloses a method and system for preparing tert-butyl acrylamide sulfonic acid, and the method comprises the following steps: mixing raw materials including acrylonitrile, a sulfonating agent, isobutene and a regulator to perform reaction, so as to obtain tert-butyl acrylamide sulfonic acid; wherein, the acrylonitrile is firstly mixed with the sulfonating agent to obtain an acrylonitrile-sulfonating agent mixture, the acrylonitrile-sulfonating agent mixture is then mixed with isobutene and a solvent, and the regulator is selected from at least one of ethers, esters, alcohols and halogenated hydrocarbons, and amides. The application provides a continuous production process of high-purity AMPS by using a one-step method, and solves the problems of long production process and unstable product quality in the prior art.

Description

Technical Field

[0001] This invention belongs to the field of tert-butylpropylene sulfonic acid preparation, and particularly relates to a method and system for preparing tert-butylacrylamide sulfonic acid. Background Technology

[0002] AMPS (2-Acrylamide-2-methylpropane sulfonic acid, hereinafter referred to as AMPS) is a multifunctional tert-butylacrylamide sulfonic acid. Its molecular structure contains carbon-carbon double bonds, amide groups and sulfonic acid functional groups. Its homopolymers and copolymers have many special properties and broad application prospects. They can be widely used in oilfield chemistry, water treatment agents, fiber synthesis, coatings, pharmaceutical hydrogels and other fields.

[0003] Chinese patent CN106748904A discloses a method for preparing 2-acrylamido-2-methylpropanesulfonate monomers, comprising the following steps: a. reacting acrylonitrile, fuming sulfuric acid, and isobutylene, and then separating the reaction product into solid and liquid phases to obtain crude 2-acrylamido-2-methylpropanesulfonate; b. adding the crude 2-acrylamido-2-methylpropanesulfonate obtained in step a to water, and adding an alkaline reagent for neutralization; c. adding acetic acid to the product obtained in step b to obtain a mixture, heating the mixture, then cooling, separating the solid and liquid phases, and drying the solid to obtain pure 2-acrylamido-2-methylpropanesulfonate monomers. This invention also provides a method for preparing 2-acrylamido-2-methylpropanesulfonate / acrylamide polymers.

[0004] However, traditional AMPS synthesis and purification processes are quite lengthy, especially since the purification process often uses highly corrosive aqueous acetic acid solutions as solvents, placing extremely high demands on the corrosion resistance of equipment during purification and solvent recovery. Furthermore, compared to batch processes, continuous production processes can reduce AMPS production costs and improve product stability. Therefore, there is an urgent need in this field for a more easily operable continuous production process for high-purity AMPS. Summary of the Invention

[0005] To overcome the problems existing in the prior art, the present invention provides a method and system for preparing tert-butylacrylamide sulfonic acid, providing a continuous production process for high-purity AMPS in a "one-step" manner, which solves the problems of lengthy AMPS production processes and unstable product quality in the prior art.

[0006] This invention provides a method for preparing tert-butylacrylamide sulfonic acid, specifically in the following aspects:

[0007] 1. A method for preparing tert-butylacrylamide sulfonic acid, comprising: mixing raw materials including acrylonitrile, sulfonating agent, isobutylene, and regulator and reacting them to obtain tert-butylacrylamide sulfonic acid.

[0008] 2. According to the method described in 1 above, wherein acrylonitrile is first mixed with a sulfonating agent to obtain an acrylonitrile-sulfonating agent mixture, and the acrylonitrile-sulfonating agent mixture is then mixed with isobutylene and a regulator;

[0009] Preferably, the acrylonitrile and the sulfonating agent are mixed at a temperature between -20°C and 10°C.

[0010] 3. The method according to 1 above, wherein the regulator is selected from at least one of ethers, esters, alcohols, halogenated hydrocarbons, and amides;

[0011] Preferably, the ether is selected from at least one of diethyl ether and methyl tert-butyl ether; and / or, the ester is selected from at least one of ethyl acetate and butyl acetate; and / or, the alcohol is selected from at least one of methanol and ethanol; and / or, the halogenated hydrocarbon is selected from at least one of dichloroethane and trichloroethane; and / or, the amide is selected from at least one of N,N-dimethylformamide and N,N-dimethylacetamide.

[0012] 4. According to the method described in 1 above, the molar ratio of isobutylene, sulfonating agent, acrylonitrile and regulator is 1:(0.9-1.1):(5-25):(0.02-0.5).

[0013] 5. According to the method described in 1 above, wherein,

[0014] The reaction is carried out in a reaction vessel, which is provided with a reaction product outlet and at least three inlets, the three inlets being an acrylonitrile-sulfonating agent mixture inlet, an isobutylene inlet, and a regulator inlet; and / or

[0015] The reaction is carried out at 10–60°C, preferably 20–55°C.

[0016] 6. The method according to any one of 1 to 5 above, wherein the method further comprises: ripening, solid-liquid separation, and drying after the reaction.

[0017] 7. According to the method described in 6 above, wherein,

[0018] The curing temperature is 5–65°C, and / or the curing time is 0.5–5 hours; and / or,

[0019] The solid-liquid separation employs at least one of the following: atmospheric pressure filtration, vacuum filtration, and centrifugal separation.

[0020] Another aspect of the present invention is to provide a system for preparing tert-butylacrylamide sulfonic acid, for carrying out the method described in the first aspect of the present invention, specifically embodied in the following aspects:

[0021] 8. A system for preparing tert-butylacrylamide sulfonic acid, the system comprising a reaction vessel having a reaction product outlet and at least three inlets, the three inlets being an acrylonitrile-sulfonating agent mixture inlet, an isobutylene inlet, and a regulator inlet.

[0022] 9. The system according to 8 above, wherein,

[0023] The reaction vessel is equipped with a stirring device and a temperature control device; and / or,

[0024] The system further includes a mixing vessel for mixing acrylonitrile and a sulfonating agent; preferably, the mixing vessel is connected to the reaction vessel, and more preferably to the acrylonitrile-sulfonating agent mixture inlet of the reaction vessel.

[0025] 10. The system according to 8 or 9 above, wherein the system further includes a curing vessel and a separation device, wherein the curing vessel is connected to the reaction product outlet of the reactor, and the curing vessel is further connected to the separation device.

[0026] 11. The system according to 10 above, wherein,

[0027] The separation device is a filtration device and / or a centrifuge device; and / or,

[0028] The system further includes a drying device, preferably connected to the separation device.

[0029] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values; these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. In the following, various technical solutions can, in principle, be combined with each other to obtain new technical solutions, which should also be considered as specifically disclosed herein.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) By introducing a regulator as a second solvent, the present invention uses a "dual solvent system" to separate AMPS from byproducts during the reaction process, and can obtain high-purity AMPS products in one step.

[0032] (2) The purity of tert-butylacrylamide sulfonic acid prepared by the method or system described in this invention is above 98.5%, and the purity is above 99% under optimized conditions. Attached Figure Description

[0033] Figure 1 A schematic diagram of the system described in this invention is shown;

[0034] exist Figure 1 In the middle, 1-mixing vessel, 2-reaction vessel, 3-aging vessel, 4-separation device, 5-drying device. Detailed Implementation

[0035] The present invention will now be described in detail with reference to specific embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0036] It should also be noted that the various specific technical features described in the following embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the various possible combinations will not be described separately in this invention.

[0037] Furthermore, various embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention. The resulting technical solutions are part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0038] One of the objectives of this invention is to provide a method for preparing tert-butylacrylamide sulfonic acid, comprising: mixing raw materials including acrylonitrile, sulfonating agent, isobutylene, and regulator and reacting them to obtain tert-butylacrylamide sulfonic acid.

[0039] In a preferred embodiment, the sulfonating agent is selected from sulfuric acid or fuming sulfuric acid.

[0040] In a further preferred embodiment, the concentration of the sulfuric acid is 98–103% by weight, preferably 100–102% by weight.

[0041] In a preferred embodiment, acrylonitrile is first mixed with a sulfonating agent to obtain an acrylonitrile-sulfonating agent mixture, and the acrylonitrile-sulfonating agent mixture is then mixed with isobutylene and a regulator.

[0042] In a further preferred embodiment, the acrylonitrile and the sulfonating agent are mixed at a temperature between -20°C and 10°C, for example, at -20°C, -15°C, -10°C, -5°C, 0°C, 5°C, or 10°C.

[0043] In a preferred embodiment, the regulator is selected from at least one of ethers, esters, alcohols, halogenated hydrocarbons, and amides, preferably from at least one of ethers and esters.

[0044] In a further preferred embodiment, preferably, the ether is selected from at least one of diethyl ether and methyl tert-butyl ether; and / or, the ester is selected from at least one of ethyl acetate and butyl acetate; and / or, the alcohol is selected from at least one of methanol and ethanol; and / or, the halogenated hydrocarbon is selected from at least one of dichloroethane and trichloroethane; and / or, the amide is selected from at least one of N,N-dimethylformamide and N,N-dimethylacetamide.

[0045] In a preferred embodiment, the molar ratio of isobutylene, sulfonating agent, acrylonitrile, and regulator is 1:(0.9-1.1):(5-25):(0.02-0.5), preferably 1:(0.95-1.05):(8-18):(0.05-0.2).

[0046] For example, the molar ratio of isobutylene to sulfonating agent is 1:0.9, 1:0.95, 1:1, 1:1.05, or 1:1.1; and / or, the molar ratio of isobutylene to acrylonitrile is 1:5, 1:10, 1:15, 1:20, or 1:25; and / or, the molar ratio of isobutylene to regulator is 1:0.02, 1:0.05, 1:0.08, 1:0.1, 1:0.12, 1:0.15, 1:0.18, 1:0.2, 1:0.25, 1:0.3, 1:0.35, 1:0.4, 1:0.45, or 1:0.5.

[0047] In a preferred embodiment, the reaction is carried out in a reaction vessel, which is provided with a reaction product outlet and at least three feed inlets, namely an acrylonitrile-sulfonating agent mixture feed inlet, an isobutylene feed inlet, and a regulator feed inlet.

[0048] In a further preferred embodiment, the reaction product outlet is closed in the initial stage of the reaction. When the material in the reactor reaches 50-70% of the reactor capacity, a stable reaction stage is reached, and the reaction product outlet is opened at this time.

[0049] In a further preferred embodiment, during the stabilization reaction stage, the discharge rate of the reactor is the same as the feed rate, so as to maintain a constant amount of material in the reactor.

[0050] In a preferred embodiment, the reaction is carried out at 10–60°C, preferably 20–55°C, for example at 10°C, 20°C, 30°C, 40°C, 50°C or 60°C.

[0051] In a preferred embodiment, the method further includes: ripening, solid-liquid separation, and drying after the reaction.

[0052] In a further preferred embodiment, the curing temperature is 5–65°C, preferably 10–55°C; and / or, the curing time is 0.5–5 h, preferably 0.5–2 h.

[0053] For example, the curing temperature is 5℃, 10℃, 15℃, 20℃, 25℃, 30℃, 35℃, 40℃, 45℃, 50℃, 55℃, 60℃ or 65℃; the curing time is 0.5h, 15h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h or 5h.

[0054] In a further preferred embodiment, the curing process is carried out in a curing vessel and can be transferred to the next step in batches or continuously, depending on the situation.

[0055] In a preferred embodiment, the solid-liquid separation employs at least one of atmospheric pressure filtration, vacuum filtration, and centrifugal separation.

[0056] In a further preferred embodiment, the product is cooled, preferably to room temperature, before the separation process, for example, to obtain a slurry product; and / or, after the separation process, the solid phase is taken and dried, for example, the slurry product is filtered to obtain a filter cake and a filtrate.

[0057] Preferably, the drying is vacuum drying.

[0058] More preferably, the vacuum drying conditions can be conventional conditions, such as a drying temperature of 50–130°C and a drying pressure of less than 30 kPa, and the resulting dried product is an AMPS product.

[0059] In this invention, acrylonitrile is both a reactant and a first solvent, and the modifier can be used as a second solvent. Therefore, this invention uses a "dual solvent system" to improve the purity of AMPS.

[0060] A second objective of this invention is to provide a system for preparing tert-butylacrylamide sulfonic acid, for carrying out the method described in one objective of this invention. The system includes a reaction vessel, on which a reaction product outlet and at least three inlets are provided. The three inlets are an acrylonitrile-sulfonating agent mixture inlet, an isobutylene inlet, and a regulator inlet.

[0061] In a preferred embodiment, the reactor has a stirring device and a temperature control device.

[0062] In a preferred embodiment, the system further includes a mixing vessel for mixing acrylonitrile and a sulfonating agent.

[0063] In a further preferred embodiment, the mixing vessel is connected to the reaction vessel, preferably to the acrylonitrile-sulfonating agent mixture inlet of the reaction vessel.

[0064] In a preferred embodiment, the system further includes a curing vessel and a separation device, wherein the curing vessel is connected to the reaction product outlet of the reactor, and the curing vessel is further connected to the separation device.

[0065] In a further preferred embodiment, the separation device is a filtration device and / or a centrifuge device.

[0066] In a preferred embodiment, the system further includes a drying device, preferably connected to the separation device.

[0067] The system described in this invention may further optionally include several other storage tanks and solvent recovery devices.

[0068] The main operating steps of the method or system described in this invention are as follows:

[0069] 1. The mixing vessel is equipped with a stirring device and a temperature control device. Sulfonating agent and acrylonitrile are added to the mixing vessel in a certain proportion at low temperature, wherein acrylonitrile is both a reactant and the primary solvent, and the mixture continuously enters the reaction vessel from the outlet.

[0070] 2. The reactor is equipped with a stirring device and a temperature control device, and includes at least three feed inlets and one discharge outlet. The first feed inlet continuously feeds a mixture of acrylonitrile and sulfonating agent; the second feed inlet feeds a certain amount of regulator; and the third feed inlet feeds isobutylene. The three feed streams react at a certain temperature.

[0071] 3. The slurry that generates AMPS is transferred from the outlet of the reactor to the maturation vessel at a certain speed.

[0072] 4. Perform solid-liquid separation on the matured AMPS, and then vacuum dry it to obtain crude AMPS.

[0073] During the preparation of AMPS, side reactions occur, generating byproducts such as tert-butylacrylamide, methylpropenesulfonic acid, and tert-butylacrylamide disulfonic acid. These byproducts affect product purity and adversely impact the application of AMPS in polymerization reactions. These byproducts have poor solubility in acrylonitrile and will co-crystallize directly with the AMPS product during the reaction, requiring removal in subsequent purification processes. This invention introduces a regulator as a second solvent, employing a "dual-solvent system" during the reaction to achieve separation of AMPS and byproducts, thus obtaining a high-purity AMPS product in one step.

[0074] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values; these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. In the following, various technical solutions can, in principle, be combined with each other to obtain new technical solutions, which should also be considered as specifically disclosed herein.

[0075] [Examples and Comparative Examples]

[0076] Unless otherwise specified, the raw materials used in the examples and comparative examples are all disclosed in the prior art, such as those that can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0077] The purity of the AMPS product was analyzed by liquid chromatography. The analytical conditions for liquid chromatography were: Zorbax SAX column, mobile phase of 0.1 mol / L KH2PO4 solution, flow rate of 1.0 mL / min, and UV detector.

[0078] The yield of AMPS product is calculated based on the amount of isobutylene feedstock added and the weight of the obtained AMPS product.

[0079] Example 1

[0080] This reaction is carried out in a device equipped with a mixing vessel, a reaction vessel, a curing vessel, a filter, and a drying oven. Before the continuous reaction begins, acrylonitrile is first added to the mixing vessel and the temperature is adjusted to -5°C. Then, sulfuric acid with a concentration of 100.4% is slowly added until the molar ratio of sulfuric acid to acrylonitrile reaches 1:10. At this point, the discharge valve of the mixing vessel is opened, and the material is added to the reaction vessel. The temperature in the reaction vessel is 40°C. Initially, the discharge port of the reaction vessel is kept closed, and isobutylene is introduced in proportion until a certain liquid level is reached. Then, the discharge port of the reaction vessel is opened, and the continuous reaction begins. After the continuous reaction begins, diethyl ether is added to the inlet of the reaction vessel, wherein the molar ratio of isobutylene, sulfuric acid, acrylonitrile, and diethyl ether is 1:1:10:0.075.

[0081] The addition rates of each material in the above process are as follows: acrylonitrile is added to the mixing vessel at a rate of 3300 g / h, sulfuric acid at a rate of 610 g / h, isobutylene at a rate of 350 g / h, diethyl ether at a rate of 35 g / h, and the discharge rate from the reaction vessel is approximately 4260 g / h. The reactants are then introduced into a ripening vessel and ripened at 40°C for 1 hour. The reaction solution is then filtered. After filtration, a filter cake and filtrate are obtained. The filter cake is then vacuum dried at 100°C and 10 kPa. The resulting AMPS product has a yield of approximately 91.8% and a purity of 99.1%.

[0082] Example 2

[0083] The difference from Example 1 lies in the addition rates of the materials: acrylonitrile at 3300 g / h, sulfuric acid at 610 g / h, isobutylene at 350 g / h, diethyl ether at 70 g / h, and the discharge rate from the reactor valve at approximately 4260 g / h. The molar ratio of isobutylene, sulfuric acid, acrylonitrile, and diethyl ether is 1:1:10:0.15. The materials are fed into a ripening reactor and ripened at 40°C for 1 hour. The reaction solution is then filtered. Filter cake and filtrate are obtained after filtration. The filter cake is vacuum dried at 100°C and 10 kPa, yielding AMPS product with a yield of approximately 88.2% and a purity of 99.2%.

[0084] Example 3

[0085] The difference from Example 1 lies in the addition rates of each material: acrylonitrile was added to the mixing vessel at a rate of 3300 g / h, sulfuric acid at a rate of 610 g / h, isobutylene at a rate of 350 g / h, diethyl ether at a rate of 10 g / h, and the discharge rate from the reaction vessel was approximately 4260 g / h. The molar ratio of isobutylene, sulfuric acid, acrylonitrile, and diethyl ether was 1:1:10:0.02. The materials were fed into a ripening vessel and ripened at 40°C for 1 hour. The reaction solution was then filtered. A filter cake and filtrate were obtained after filtration. The filter cake was vacuum dried at 100°C and 10 kPa, yielding AMPS product with a yield of approximately 92.1% and a purity of 99.0%.

[0086] Example 4

[0087] The difference from Example 1 is that ethyl acetate was used as the second solvent, and the addition rates of each material were as follows: acrylonitrile was added to the mixing vessel at a rate of 3300 g / h, sulfuric acid at a rate of 610 g / h, isobutylene at a rate of 350 g / h, ethyl acetate at a rate of 53 g / h, and the discharge rate from the reaction vessel was approximately 4260 g / h. The molar ratio of isobutylene, sulfuric acid, acrylonitrile, and diethyl ether was 1:1:10:0.1. The materials were fed into a ripening vessel and ripened at 40°C for 1 hour. The reaction solution was then filtered. A filter cake and filtrate were obtained after filtration. The filter cake was vacuum dried at 100°C and 10 kPa, yielding AMPS product with a yield of approximately 92.3% and a purity of 99.1%.

[0088] Example 5

[0089] The difference from Example 1 is that ethyl acetate was used as the second solvent, and the reaction temperature was changed to 25°C. The addition rates of each material are as follows: acrylonitrile 3300 g / h, sulfuric acid 610 g / h, isobutylene 350 g / h, ethyl acetate 53 g / h, and the discharge rate from the reactor valve is approximately 4260 g / h. The molar ratio of isobutylene, sulfuric acid, acrylonitrile, and diethyl ether is 1:1:10:0.1. The materials are fed into a ripening reactor and ripened at 25°C for 1 hour. The reaction solution is then filtered. Filter cake and filtrate are obtained after filtration. The filter cake is vacuum dried at 100°C and 10 kPa. The resulting AMPS product has a yield of approximately 91.5% and a purity of 98.7%.

[0090] Example 6

[0091] The difference from Example 1 is that ethyl acetate was used as the second solvent, and the proportions of the raw materials were changed. The addition rates of each material were as follows: acrylonitrile was added at 3700 g / h, sulfuric acid at 610 g / h, isobutylene at 350 g / h, ethyl acetate at 85 g / h, and the discharge rate from the reactor was approximately 4260 g / h. The molar ratio of isobutylene, sulfuric acid, acrylonitrile, and diethyl ether was 1:1:11.2:0.15. The materials were fed into a ripening reactor and ripened at 40°C for 1 hour. The reaction solution was then filtered. Filter cake and filtrate were obtained after filtration. The filter cake was vacuum dried at 100°C and 10 kPa. The resulting AMPS product had a yield of approximately 90.8% and a purity of 99.3%.

[0092] Comparative Example 1

[0093] The process of Example 1 is repeated, except that: Comparative Example 1 is used to illustrate the continuous synthesis of AMPS without the use of a regulator.

[0094] The addition rates of each material are as follows: acrylonitrile is added to the mixing vessel at a rate of 3300 g / h, sulfuric acid at a rate of 610 g / h, isobutylene at a rate of 350 g / h, and the discharge rate from the reaction vessel is approximately 4260 g / h. The molar ratio of isobutylene, sulfuric acid, and acrylonitrile is 1:1:10. The materials are then added to a ripening vessel and ripened at 40°C for 1 hour. The reaction solution is then filtered. Filter cake and filtrate are obtained after filtration. The filter cake is then vacuum dried at 100°C and 10 kPa. The resulting AMPS product has a yield of approximately 91.7% and a purity of 96.4%.

[0095] A comparison of the examples with Comparative Example 1 shows that the method provided by the present invention can effectively reduce the content of by-products and improve the purity of AMPS.

[0096] Comparative Example 2

[0097] The process of Example 1 was repeated, except that no diethyl ether was added during the synthesis process, but the filter cake was washed with diethyl ether after filtration, and the washed filter cake was vacuum dried at a temperature of 100°C and a pressure of 10 kPa. After drying, the AMPS product was obtained with a yield of approximately 90.7% and a purity of 96.9%.

[0098] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A method for preparing tert-butylacrylamide sulfonic acid, comprising: The raw materials, including acrylonitrile, sulfonating agent, isobutylene, and regulator, are mixed and reacted. First, acrylonitrile and sulfonating agent are mixed to obtain an acrylonitrile-sulfonating agent mixture. The acrylonitrile-sulfonating agent mixture is then mixed with isobutylene and regulator to obtain tert-butylacrylamide sulfonic acid. The sulfonating agent is sulfuric acid, and the regulator is selected from at least one of diethyl ether and ethyl acetate. The molar ratio of isobutylene, sulfonating agent, acrylonitrile, and regulator is 1:(0.9~1.1):(5~25):(0.02~0.2).

2. The method according to claim 1, characterized in that, The acrylonitrile and the sulfonating agent are mixed at a temperature between -20°C and 10°C.

3. The method according to claim 1, characterized in that, The reaction is carried out in a reaction vessel, which is provided with a reaction product outlet and at least three feed inlets, namely an acrylonitrile-sulfonating agent mixture feed inlet, an isobutylene feed inlet, and a regulator feed inlet.

4. The method according to claim 1, characterized in that, The reaction was carried out at 10~60℃.

5. The method according to claim 1, characterized in that, The reaction was carried out at 20–55 °C.

6. The method according to any one of claims 1 to 5, characterized in that, The method further includes: ripening, solid-liquid separation, and drying after the reaction.

7. The method according to claim 6, characterized in that, The ripening temperature is 5~65℃.

8. The method according to claim 6, characterized in that, The ripening time is 0.5 to 5 hours.

9. The method according to claim 6, characterized in that, The solid-liquid separation employs at least one of the following: atmospheric pressure filtration, vacuum filtration, and centrifugal separation.

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