Solid acid-binding agent and method for its preparation and use

Abstract

The application provides a solid acid-binding agent and a preparation method and application thereof, and the structure of the solid acid-binding agent is shown in the following formula. The solid acid-binding agent prepared by the application can remove hydrogen chloride in a reaction without using triethylamine, and the subsequent processes such as centrifugation and triethylamine recovery are omitted, and the solid acid-binding agent can be recycled, and has obvious cost advantage.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of organic synthesis, and particularly relates to a solid acid-binding agent and a preparation method and application thereof. BACKGROUND

[0002] At present, the process route of the industrial production of vinylene carbonate is mainly triethylamine and chloroethylene carbonate route: CEC (chloroethylene carbonate) is used as a solvent in DMC (dimethyl carbonate) and is removed from hydrogen chloride in a reaction kettle under the catalysis of triethylamine. The solution containing solid triethylamine hydrochloride is filtered by centrifugation, and then the solution is introduced into a desolventizing tower, a crude distillation tower, a rectification tower and a crystallizer to obtain qualified vinylene carbonate product. The triethylamine used as an acid-binding agent has the problems of strong reaction alkalinity, many side reactions and low product yield, and the recovery of the generated triethylamine hydrochloride needs to consume a large amount of liquid alkali for neutralization, generates waste brine, and the recovery process is complicated, the cost is high, the environmental protection pressure is large.

[0003] The current industrial route of vinylene carbonate has the following disadvantages: (1) the process route is complicated, involves the operation of various solid materials, cannot realize automatic and continuous production, and has high safety risks. (2) The overall reaction yield of the product is not high, a large amount of chlorine-containing solid hazardous waste, acid gas and tar are generated in the production process, the treatment cost is high, and the environmental protection pressure is large. (3) The vinylene carbonate synthesized by the route contains a large amount of by-products and chlorides, which makes the subsequent separation and purification more difficult, and repeated distillation and crystallization are needed to reach 99.995% content. Therefore, the prior art needs to be further developed. SUMMARY

[0004] In view of various deficiencies of the prior art, in order to solve the above problems, a solid acid-binding agent and a preparation method and application thereof are provided. The following technical solutions are provided:

[0005] The present application provides a solid acid-binding agent, the structure is as follows:

[0006] .

[0007] In addition, the application further provides a preparation method of the solid acid-binding agent, and the preparation steps are as follows: (1) performing a first Mannich reaction: adding ethylenediamine and paraformaldehyde in an alcohol solution, controlling the pH value to be 1-3, and reacting at 30-50 DEG C for 2-3 h, then increasing the temperature to 60-90 DEG C, and dropping aniline solution, after the dropping is completed, and then reacting for 14-16 h; (2) performing a second Mannich reaction: after the first Mannich reaction, continuing to add paraformaldehyde, controlling the pH value to be 1-3, and reacting at 30-50 DEG C for 2-3 h, then increasing the temperature to 60-90 DEG C, and dropping aniline solution, after the dropping is completed, and then reacting for 14-16 h; (3) after the second Mannich reaction, decreasing the temperature, and filtering to obtain the solid acid-binding agent.

[0008] Further, in the first Mannich reaction, the molar ratio of the reaction raw materials ethylenediamine, paraformaldehyde and aniline is 1: (2.3-2.5) : 1.

[0009] Further, in the first Mannich reaction, the pH value is controlled by using a hydrochloric acid solution.

[0010] Further, in the first Mannich reaction, the dropping time of the aniline solution is 2-3 h, and the solvent of the aniline solution is an alcohol solvent.

[0011] Further, in the second Mannich reaction, the molar ratio of the formaldehyde and aniline is (2.3-2.5) : 1.

[0012] Further, in the second Mannich reaction, the pH value is controlled by using a hydrochloric acid solution.

[0013] Further, in the second Mannich reaction, the dropping time of the aniline solution is 2-3 h, and the solvent of the aniline solution is an alcohol solvent.

[0014] The application further provides an application of the solid acid-binding agent, and the solid acid-binding agent is used to remove hydrogen chloride in the synthesis of vinylene carbonate to obtain the vinylene carbonate.

[0015] Further, after the solid acid-binding agent is pressed into tablets and crushed, the solid acid-binding agent is filled into a packing tower, chloroethylene carbonate and diethyl carbonate are mixed and then punched into the packing tower to stay for 3-5 min, and the solid acid-binding agent can be recycled by being treated at high temperature to resolve hydrogen chloride.

[0016] Advantages:

[0017] 1. The application prepares a novel solid acid-binding agent, and hydrogen chloride in the reaction can be removed without using triethylamine, and subsequent centrifugation, triethylamine recovery and other processes are saved, and the solid acid-binding agent can be recycled by being treated at high temperature to resolve hydrogen chloride, and has obvious cost advantage.

[0018] 2. The use of the solid acid-binding agent in the synthesis of vinylene carbonate in the present application makes the synthesis of vinylene carbonate have less side reactions, high reaction liquid content, and less impurities, and high-purity vinylene carbonate can be obtained by simple rectification subsequently, which is simple in operation, low in cost, and green and environmentally friendly. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a reaction schematic diagram of the preparation of the solid acid-binding agent of the present application. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the technical solutions of the present application, the technical solutions of the present application will be described clearly and completely below in combination with the embodiments of the present application, and other similar embodiments obtained by those skilled in the art on the basis of the embodiments in the present application without creative labor shall all belong to the scope of protection of the present application.

[0021] According to an embodiment of the present application, a solid acid-binding agent is provided, which has the following structure:

[0022] .

[0023] The present application prepares a new type of solid acid-binding agent, which can remove hydrogen chloride in the reaction without using triethylamine, thereby saving subsequent processes such as centrifugation and triethylamine recovery, and the solid acid-binding agent can be recycled after being treated at high temperature by resolving hydrogen chloride, thereby having obvious cost advantage.

[0024] The preparation method of the solid acid-binding agent is as shown in Figure 1 , and the preparation steps are as follows: (1) first Mannich reaction: in an alcohol solution, add ethylenediamine and paraformaldehyde, control the pH value to be 1-3, react at 30-50 DEG C for 2-3 h, then increase the temperature to 60-90 DEG C, and drop the aniline solution, after the dropping is completed, keep the reaction for 14-16 h; (2) second Mannich reaction: after the first Mannich reaction, continue to add paraformaldehyde while cooling, control the pH value to be 1-3, react at 30-50 DEG C for 2-3 h, then increase the temperature to 60-90 DEG C, and drop the aniline solution, after the dropping is completed, keep the reaction for 14-16 h; (3) after the second Mannich reaction, cool, and filter to obtain the solid acid-binding agent. The present application uses simple raw materials such as paraformaldehyde, ethylenediamine, and aniline to synthesize a solid acid-binding agent, which is used for the synthesis of vinylene carbonate, and the solid acid-binding agent can be regenerated in situ after use, thereby simplifying the production process and reducing the production cost. The use of triethylamine is avoided in the synthesis process of vinylene carbonate, thereby saving subsequent processes such as centrifugation and triethylamine recovery, and the production adopts a continuous packed column reaction, only two packed columns are needed for regeneration by switching back and forth, the solid acid-binding agent can be recycled, and has obvious cost advantage.

[0025] The solid acid-binding agent can be recycled and regenerated by high-temperature dehydrochlorination gas. The solid acid-binding agent is washed twice with diethyl carbonate, then heated to 130-150°C under vacuum, and most of the adsorbed hydrogen chloride is released in the form of gas. Then, after cooling, the residual hydrogen chloride is replaced by washing with a 2-3% alkali solution. The regenerated solid acid-binding agent after activation can be recycled.

[0026] To improve the use effect and service life of the solid acid-binding agent, in the synthesis of vinylene carbonate, the raw material chloroethylene carbonate is purified by rectification to remove impurities such as tar and dichloroethylene carbonate. The content of chloroethylene carbonate is ≥98%, the mass ratio of chloroethylene carbonate to diethyl carbonate is 1:(2-4), the reaction temperature is 70-90°C, and the residence time of the reaction material in the tower is ≥2 min.

[0027] Example 1

[0028] A glass four-necked flask with stirring and thermometer is prepared. Under nitrogen protection, 60.1g of ethylenediamine (1mol) and 69g of polyformaldehyde (2.3mol) are weighed into 300ml of methanol, stirring is started, and a small amount of concentrated hydrochloric acid is added to adjust the pH value to 1. The reaction is carried out at 35°C for 3h. After the reaction is completed, the temperature is raised to 65°C. 93.1g of aniline (1mol) is dissolved in 300ml of ethanol solvent, and slowly added to the four-necked flask. The dropping time is 3h. After the addition is completed, the temperature is slowly raised to reflux state, and the reaction is continued for 15h. After the reaction is completed, the temperature is lowered to 35°C. 69g of polyformaldehyde solid and a small amount of hydrochloric acid are added to control the pH value to 1. The reaction temperature is controlled at 35°C for 3h. Then, the temperature is raised to 65°C. 93.1g of aniline (1mol) is dissolved in 300ml of methanol solvent, and slowly added to the four-necked flask. The dropping time is 3h. After the addition is completed, the temperature is slowly raised to reflux state, and the reaction is continued for 15h. After the reaction is completed, the solid material is filtered and dried to obtain 273.0g of solid. The solid is pressed into tablets by a tablet press at 20MPa, and then added to a filler column with jacketed cooling water. 90g of chloroethylene carbonate (purity 98.6%) is added to 180g of diethyl carbonate to form a solution. The solution is heated to 75°C, and then pumped into the filler column by a metering pump. The residence time of the solution is controlled at 3-5min. After the reaction is completed, 234.9g of solution is obtained, with a vinylene carbonate content of 22.1% and a yield of 83.33%.

[0029] Example 2

[0030] A glass four-necked flask with stirring and thermometer was prepared, and 60.1 g of ethylenediamine (1 mol) and 75 g of paraformaldehyde (2.5 mol) were weighed into 300 ml of ethanol under the condition of nitrogen protection, and a small amount of concentrated hydrochloric acid was added to adjust the pH value to 3.0, and the stirring was started. The reaction was carried out at 50°C for 3 h. After the reaction was completed, the temperature was raised to 75°C. 93.1 g of aniline was dissolved in methanol solvent, and was slowly added to the four-necked flask. The dropping time was 2 h. After the dropping was completed, the temperature was slowly raised to reflux state, and the reaction was continued for 16 h. Then, 75 g of paraformaldehyde (2.5 mol) solid and a small amount of hydrochloric acid were added to adjust the pH value to 3.0, and the reaction was carried out at 50°C for 3 h. Then, the temperature was raised to 75°C. 93.1 g of aniline (1 mol) was dissolved in 300 ml of ethanol solvent, and was slowly added to the four-necked flask. The dropping time was 2 h. After the dropping was completed, the reaction was carried out at reflux state for 16 h. After the reaction was completed, filtration and drying were carried out to obtain 281.3 g of solid material. The solid material was pressed into tablets by a tablet press at 20 MPa, and was then added to a filler column with jacketed cooling water. 90 g of chloroethylene carbonate (purity 98.6%) was weighed, and was added to 180 g of diethyl carbonate to form a solution. The solution was heated to 75°C, and was pumped into the filler column by a metering pump. The residence time of the solution was controlled to be 3-5 min. After the reaction was completed, 226.3 g of solution was obtained, the content of vinylene carbonate was 24.4%, and the yield was 88.86%.

[0031] Example 3

[0032] A glass four-necked flask with stirring and thermometer was prepared, and 60.1 g of ethylenediamine (1 mol) and 72 g of polyformaldehyde (2.4 mol) were weighed into 300 ml of ethylene glycol under the condition of nitrogen protection, and a small amount of concentrated hydrochloric acid was added to adjust the pH value to 2, and the reaction was carried out at 30°C for 2 h. After the reaction was completed, the temperature was increased to 90°C, 93.1 g of aniline (1 mol) was dissolved in 300 ml of ethylene glycol solvent, and the aniline ethylene glycol solution was slowly added to the four-necked flask, and the dropping time was 3 h. After the addition was completed, the temperature was slowly increased to reflux, and the reaction was continued for 14 h. After cooling, 69 g of polyformaldehyde solid and a small amount of hydrochloric acid were added to control the pH value to 2, and the reaction was carried out at 30°C for 2 h. Then the temperature was increased to 90°C, 93.1 g of aniline (1 mol) was dissolved in 300 ml of ethylene glycol solvent, and the aniline ethylene glycol solution was slowly added to the four-necked flask, and the dropping time was 3 h. After the addition was completed, the temperature was slowly increased to reflux, and the reaction was continued for 14 h. After cooling, the solid material 275.5 g was obtained by filtration and drying. The solid was granulated into tablets by using a tablet press at 20 MPa, and then added to a filler column with jacketed cooling water. 90 g of chloroethylene carbonate (purity 98.6%) was added to 180 g of diethyl carbonate to form a solution, which was heated to 75°C and pumped into the filler column. The residence time of the solution was controlled to be 3-5 min. After the reaction was completed, a solution 235.7 g was obtained, the content of vinylene carbonate was 23.2%, and the yield was 86.75%.

[0033] Example 4

[0034] The used solid acid-binding agent in Example 1 was washed twice with solvent diethyl carbonate, heated to 140°C and vacuum degassed (1 KPa absolute pressure) for 2 h, then washed once with 2% NaOH aqueous solution and dried under vacuum for continuous use. 90 g of chloroethylene carbonate (purity 98.6%) was added to 180 g of diethyl carbonate to form a solution, which was heated to 75°C and pumped into the filler column with activated solid acid-binding agent. The residence time of the solution was controlled to be 3-5 min. After the reaction was completed, a solution 236.3 g was obtained, the content of vinylene carbonate was 21.2%, and the yield was 80.41%.

[0035] Example 5

[0036] The solid acid-binding agent used in Example 2 was washed twice with solvent diethyl carbonate, vacuum degassed (1 KPa absolute pressure) at 140°C for 2 h, then washed once with 2% NaOH aqueous solution, and then used again after vacuum drying. 90 g of chloroethylene carbonate (purity 98.6%) was weighed, 180 g of diethyl carbonate was added to form a solution, the solution was warmed to 75°C, and then pumped into a column filled with the activated solid acid-binding agent through a metering pump, with a solution residence time of 3-5 min. After the reaction was completed, 228.32 g of solution was obtained, with a vinylene carbonate content of 23.2%, and a yield of 85.02%.

[0037] Example 6

[0038] The solid acid-binding agent used in Example 3 was washed twice with solvent diethyl carbonate, vacuum degassed (1 KPa absolute pressure) at 140°C for 2 h, then washed once with 2% NaOH aqueous solution, and then used again after vacuum drying. 90 g of chloroethylene carbonate (purity 98.6%) was weighed, 180 g of diethyl carbonate was added to form a solution, the solution was warmed to 75°C, and then pumped into a column filled with the activated solid acid-binding agent through a metering pump, with a solution residence time of 3-5 min. After the reaction was completed, 238.5 g of solution was obtained, with a vinylene carbonate content of 23.3%, and a yield of 87.95%.

[0039] Comparative Example 1

[0040] A glass four-necked flask with stirring and a thermometer was prepared, and under nitrogen protection conditions, 60.1 g of ethylenediamine (1 mol) and 72 g of polyformaldehyde (2.4 mol) were weighed into 300 ml of methanol, stirring was started, and the reaction was carried out at 30°C for 2 h. After the reaction was completed, the temperature was increased to 65°C, 93.1 g of aniline (1 mol) was dissolved in methanol solvent, and the aniline solution was slowly added to the four-necked flask over a period of 3 h. After the addition was completed, the temperature was slowly increased to reflux, and the reaction was continued for 14 h. Then, 69 g of polyformaldehyde solid was added, the reaction temperature was controlled at 30°C for 2 h, and then the temperature was increased to 65°C. 93.1 g of aniline (1 mol) was dissolved in ethanol solvent, and the aniline solution was slowly added over a period of 3 h. After the addition was completed, the reaction was carried out at reflux for 16 h. After the heat preservation was completed, the reaction liquid was found to contain a large amount of unreacted aniline and hexanediamine by gas chromatography.

[0041] Comparative Example 2

[0042] A glass four-necked flask with stirring and thermometer was prepared, 60.1 g of ethylenediamine (1 mol) and 72 g of polyformaldehyde (2.4 mol) were weighed and added into 300 ml of ethanol under the condition of nitrogen protection, stirring was started, a small amount of concentrated hydrochloric acid was added to adjust the pH value to 5, and the reaction was carried out at 30°C for 2 h. After the reaction was completed, the temperature was increased to 75°C, 93.1 g of aniline (1 mol) was dissolved in ethanol solvent, and the aniline solution was slowly added to the four-necked flask, the dropping time was 3 h, after the addition was completed, the temperature was slowly increased to reflux, and the reaction was continued for 14 h. After cooling, 69 g of polyformaldehyde solid and a small amount of hydrochloric acid were added to control the pH value to 5, and the reaction was carried out at 30°C for 2 h. Then the temperature was increased to 75°C, 93.1 g of aniline (1 mol) was dissolved in ethanol solvent, and the aniline solution was slowly added, the dropping time was 3 h, after the addition was completed, the temperature was kept at reflux for 14 h. After the temperature was kept, no solid was precipitated in the reaction solution, and a gas chromatograph was used to detect that the reaction solution contained a large amount of unreacted aniline and hexanediamine.

[0043] Comparative Example 3

[0044] A glass four-necked flask with stirring and thermometer was prepared, 60.1 g of ethylenediamine (1 mol) and 72 g of polyformaldehyde (2.4 mol) were weighed and added into 300 ml of ethanol under the condition of nitrogen protection, stirring was started, a small amount of concentrated hydrochloric acid was added to adjust the pH value to 5, and the reaction was carried out at 30°C for 2 h. After the reaction was completed, the temperature was increased to 75°C, 93.1 g of aniline (1 mol) was dissolved in ethanol solvent, and the aniline solution was slowly added to the four-necked flask, the dropping time was 3 h, after the addition was completed, the temperature was slowly increased to reflux, and the reaction was continued for 14 h. After cooling, 69 g of polyformaldehyde solid and a small amount of hydrochloric acid were added to control the pH value to 5, and the reaction was carried out at 30°C for 2 h. Then the temperature was increased to 75°C, 93.1 g of aniline (1 mol) was dissolved in ethanol solvent, and the aniline solution was slowly added, the dropping time was 3 h, after the addition was completed, the temperature was kept at reflux for 14 h. After the temperature was kept, no solid was precipitated in the reaction solution, and a gas chromatograph was used to detect that the reaction solution contained a large amount of unreacted aniline and hexanediamine.

[0045] Comparative Example 4

[0046] A glass four-necked flask with stirring and thermometer was prepared, 60.1 g of ethylenediamine (1 mol) and 72 g of polyformaldehyde (2.4 mol) were weighed into 300 ml of methanol under the condition of nitrogen protection, a small amount of concentrated hydrochloric acid was added to adjust the pH value to 2, and the reaction was carried out at 10°C for 2 h. After the reaction was completed, the temperature was raised to 30°C, 93.1 g of aniline (1 mol) was dissolved in ethanol solvent, and the aniline solution was slowly added dropwise to the four-necked flask, and the dropwise addition time was 3 h. After the dropwise addition was completed, the temperature was slowly raised to reflux state, and the reaction was continued for 14 h. After cooling, 69 g of polyformaldehyde solid and a small amount of hydrochloric acid were added to control the pH value to 2, and the reaction was carried out at 10°C for 2 h. Then the temperature was raised to 30°C, 93.1 g of aniline (1 mol) was dissolved in ethanol solvent, and the aniline solution was slowly added dropwise, and the dropwise addition time was 3 h. After the dropwise addition was completed, the reaction was carried out at reflux state for 14 h. After the temperature was raised, no solid was precipitated in the reaction solution, and gas chromatography was used to detect that the reaction solution contained a large amount of unreacted aniline and hexanediamine.

[0047] Comparative Example 5

[0048] No solid acid binding agent of the present application was added in the filler column, 90 g of chloroethylene carbonate (purity 98.6%) was weighed, 180 g of diethyl carbonate was added to form a solution, the solution was heated to 75°C, and the solution was pumped into the filler column through a metering pump, and the residence time of the solution was controlled at 3-5 min. After the reaction was completed, it was detected that the target product could not be obtained.

[0049] In addition, it should be understood that although the present specification is described in terms of embodiments, each embodiment does not contain only one independent technical solution, and the description manner of the specification is only for the sake of clarity. The skilled person should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by the skilled person.

Claims

1. A solid acid-binding agent, characterized in that, The structure is shown as follows: 。 2. A method for preparing the solid acid-binding agent of claim 1, comprising the following steps: (1) performing a first Mannich reaction: adding ethylenediamine and paraformaldehyde in an alcohol solution, controlling the pH value to be 1-3, and reacting at 30-50°C for 2-3 h, then increasing the temperature to 60-90°C, and dropping aniline solution, after the dropping is completed, and reacting for 14-16 h; (2) performing a second Mannich reaction: after the first Mannich reaction, continuing to add paraformaldehyde while decreasing the temperature, controlling the pH value to be 1-3, and reacting at 30-50°C for 2-3 h, then increasing the temperature to 60-90°C, and dropping aniline solution, after the dropping is completed, and reacting for 14-16 h; (3) after the second Mannich reaction, decreasing the temperature, and filtering to obtain the solid acid-binding agent.

3. The method of preparing a solid acid-binding agent according to claim 2, characterized in that, In the first Mannich reaction, the molar ratio of the raw materials ethylenediamine, paraformaldehyde, and aniline is 1:(2.3-2.5):

1.

4. The method of preparing a solid acid-binding agent according to claim 2, characterized by, In the first Mannich reaction, the pH value is controlled by using a hydrochloric acid solution.

5. The method of preparing a solid acid-binding agent according to claim 2, characterized by, In the first Mannich reaction, the dropping time of the aniline solution is 2-3 h, and the solvent of the aniline solution is an alcohol solvent.

6. The method of preparing a solid acid-binding agent according to claim 2, characterized by, In the second Mannich reaction, the molar ratio of formaldehyde and aniline is (2.3-2.5):

1.

7. The method of preparing a solid acid-binding agent according to claim 2, characterized by, In the second Mannich reaction, the pH value is controlled by using a hydrochloric acid solution.

8. The method of preparing a solid acid binding agent according to claim 2, characterized in that, In the second Mannich reaction, the dropping time of the aniline solution is 2-3 h, and the solvent of the aniline solution is an alcohol solvent.

9. Use of a solid acid-binding agent, characterized in that The solid acid-binding agent of claim 1 is used to remove hydrogen chloride in the synthesis of vinylene carbonate to obtain vinylene carbonate.

10. The use of a solid acid-binding agent according to claim 9, characterized in that After the solid acid-binding agent is pressed into tablets and crushed, it is filled into a packed column, and a mixture of chloroethylene carbonate and diethyl carbonate is injected into the packed column and stays for 3-5 min.

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