Porous crosslinked quaternary amine base resin beta-h elimination promoter, method of making and use thereof
By preparing porous cross-linked quaternary ammonium base resin as a β-H elimination promoter, the problems of large metal salt addition and difficult separation in the existing technology are solved, and the efficient carbon dioxide and ethylene carboxylation reaction is realized, which has good prospects for industrial application.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA PETROLEUM & CHEMICAL CORP
- Filing Date
- 2024-12-09
- Publication Date
- 2026-06-09
AI Technical Summary
Existing β-H elimination promoters suffer from problems such as large metal salt addition, high separation difficulty, and insufficient alkalinity, resulting in low reaction efficiency and increased energy consumption.
A resin accelerator with high exchange capacity and strong basicity was prepared by using porous cross-linked quaternary ammonium base resin as a β-H elimination promoter, and by reacting chloromethylated polystyrene cross-linked resin with triethylamine and then treating it with sodium hydroxide solution. This accelerator was used to catalyze the carboxylation reaction of carbon dioxide and ethylene.
It improves reaction efficiency, reduces separation energy consumption, and achieves high alkalinity and easy separation, showing good prospects for industrial application.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of β-H elimination promoter technology, specifically to a porous cross-linked quaternary ammonium alkali resin β-H elimination promoter, its preparation method, and its application. Background Technology
[0002] In the 1980s, Burkhart first reported the carboxylation reaction of carbon dioxide with alkenes. Using carbon dioxide and styrene as raw materials, he demonstrated that carbon dioxide could be activated to generate nickel propionate lactone intermediates under the action of a nickel complex. By controlling the reaction temperature, phenylpropionic acid or cinnamic acid products could be generated. Building on this, more and more researchers have studied the catalytic carboxylation of unsaturated hydrocarbons with carbon dioxide. Carbon dioxide carboxylation reactions can be widely used to prepare bulk and fine chemicals, as well as intermediates in organic synthesis. In recent years, palladium and nickel-catalyzed reactions of alkenes and alkynes with carbon dioxide have received considerable attention among different catalytically active metals. Some reactions have been used to prepare a series of important industrial products. For example, valuable α,β-unsaturated carboxylic acids and their derivatives can be directly obtained via carbon dioxide carboxylation reactions. The carboxylation reaction of carbon dioxide with ethylene can directly synthesize acrylic acid, which can then be further processed through esterification to obtain various acrylate compounds.
[0003] The carboxylation reaction of carbon dioxide with ethylene is a direct reaction between ethylene and carbon dioxide catalyzed by a metal catalyst. The reaction mechanism is that after the metal catalyst activates carbon dioxide, it reacts with ethylene to generate a metal lactone ring intermediate of propionate. This intermediate can be hydrolyzed or undergo β-H elimination reaction under heating or acid-base conditions. At the same time, the metal catalyst leaves and re-enters the next catalytic cycle, finally yielding acrylic acid or propionic acid compounds.
[0004] From a reaction mechanism perspective, the promoter in the β-H elimination step plays a crucial role in the reaction process. Currently, most β-H elimination promoters are metal salts of acids or alcohols. When using tert-butanol metal salts as β-H elimination promoters for carbon dioxide carboxylation reactions, the reaction yield can reach over 70%. However, the amount of potassium tert-butoxide added is usually 200-1000 times that of the catalyst, generating a large amount of waste liquid. Furthermore, the unreacted tert-butanol metal salt and potassium acrylate product are difficult to separate, leading to increased separation energy consumption. Chevron Philips Chemicals has developed polyvinylphenol or phenolic resin metal salts (CN108368017A, CN111032609A) as supported β-H elimination promoters to replace tert-butanol metal salts for the carboxylation reaction of carbon dioxide and ethylene. Although these supported β-H elimination promoters are easy to separate, their basicity is weaker than that of alcohol metal salts, resulting in lower reaction efficiency. To address the above issues, it is of great significance to develop supported β-H elimination promoters with high exchange capacity and strong basicity. Summary of the Invention
[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a porous cross-linked quaternary ammonium alkali resin β-H elimination promoter, its preparation method and application. The prepared porous cross-linked quaternary ammonium alkali resin β-H elimination promoter has advantages such as high metal salt content, strong alkalinity and easy separation, and is an additive with great prospects for industrial application.
[0006] The technical solution of this invention is as follows:
[0007] In a first aspect, the present invention provides a method for preparing a porous crosslinked quaternary ammonium alkali resin β-H elimination promoter, comprising the following steps:
[0008] S1 chloromethylated polystyrene crosslinked resin and triethylamine were stirred and heated under reflux in acetonitrile solvent;
[0009] S2 filtration removes acetonitrile and residual triethylamine, followed by washing with methanol to remove residual triethylamine and acetonitrile from the resin microspheres.
[0010] S3 dried the washed resin microspheres to remove excess methanol, then reacted them with sodium hydroxide solution at room temperature for 3-8 hours. After the reaction was completed, the resin microspheres were washed with water and methanol respectively, and finally dried to obtain porous cross-linked quaternary ammonium base resin β-H elimination promoter.
[0011] The synthesis process of the porous crosslinked quaternary ammonium alkali resin β-H elimination promoter of the present invention is as follows:
[0012]
[0013] Preferably, in step S1, the amount of triethylamine added is 30-45% of the total mass of chloromethylated polystyrene crosslinking resin and triethylamine.
[0014] Preferably, in step S1, the reflux reaction temperature is 90-110℃ and the reflux reaction time is 10-15h.
[0015] Preferably, in step S3, the concentration of the sodium hydroxide solution is 1 mol / L; the amount of sodium hydroxide added is 40-60% of the mass of the resin microspheres.
[0016] Preferably, in step S3, the amount of sodium hydroxide added is 60% of the mass of the resin microspheres.
[0017] Preferably, in step S3, the drying temperature is 50-70℃ and the drying time is 7-9h.
[0018] Secondly, the present invention provides a porous crosslinked quaternary ammonium base resin β-H elimination promoter prepared by the above preparation method, with the following structural formula:
[0019]
[0020] n = 500 - 2000.
[0021] Thirdly, the present invention provides the application of the above-mentioned porous cross-linked quaternary ammonium alkali resin β-H elimination promoter, in which ethylene and carbon dioxide react to produce acrylic acid under the catalytic action of a catalyst composed of palladium or nickel compounds, phosphine ligands and porous cross-linked quaternary ammonium alkali resin β-H elimination promoter.
[0022] Preferably, palladium or nickel compounds, phosphine ligands, and porous cross-linked quaternary ammonium alkali resin β-H elimination promoters are added to the reactor, sealed, and then an appropriate amount of carbon dioxide with a mass purity of 90-100% is introduced. Then, the reactor is filled with ethylene to a specified pressure to carry out the reaction, wherein the mass purity of ethylene is 90-100%. This reaction is a heterogeneous reaction carried out in a batch reactor.
[0023] Preferably, the nickel compound is bis-(1,5-cyclooctadiene)nickel, the palladium compound is tetratetraphenylphosphine palladium, the phosphine ligand is bidentate phosphine ligand, and the molar ratio of palladium or nickel compound, phosphine ligand and porous crosslinked benzyl alcohol resin metal salt β-H elimination promoter is 1:(1-2):(100-600).
[0024] Preferably, the phosphine ligand is 1,2-bis(dicyclohexylphosphine)ethane or 1,4-bis(dicyclohexylphosphine)propane.
[0025] Preferably, the reaction temperature is 60-90℃ and the reaction time is 12-24h.
[0026] Preferably, the reaction temperature is 70-80℃ and the reaction time is 15-20h.
[0027] In this invention, the TON of the carbon dioxide carboxylation reaction is calculated as: the number of moles of sodium acrylate produced by the reaction / the number of moles of catalyst (i.e., nickel compound and phosphine ligand) added.
[0028] Compared with the prior art, the present invention has the following advantages:
[0029] The porous cross-linked quaternary ammonium alkali resin β-H elimination promoter prepared by this invention has a high exchange capacity, not less than 4.6 mmol / g, and the amount added during the reaction is further reduced. It is more basic than sodium phenolate and has a faster reaction efficiency. Furthermore, using the porous cross-linked quaternary ammonium alkali resin of this invention as a β-H elimination promoter facilitates separation from the reactants and products, reducing separation energy consumption. Therefore, the porous cross-linked quaternary ammonium alkali resin β-H elimination promoter prepared by this invention has advantages such as high metal salt content, strong basicity, and easy separation, making it a promising additive for industrial application. Detailed Implementation
[0030] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of this invention will be clearly and completely described below in conjunction with the embodiments of this invention.
[0031] Example 1
[0032] In a 250 mL round-bottom flask, 20 g of chloromethylated polystyrene crosslinking resin, 10 g of triethylamine, and 200 mL of anhydrous acetonitrile were added sequentially. The mixture was stirred thoroughly and refluxed at 90 °C for 10 h. The reaction was then stopped and cooled to room temperature. The triethylamine and acetonitrile solvents were separated by filtration using a Buchner funnel. Simultaneously, the resin microspheres were washed with methanol to remove residual triethylamine and acetonitrile. The washed resin microspheres were then dried in a vacuum oven at 50 °C for 6 h to remove excess methanol. 20 g of resin microspheres were then transferred to a 500 mL round-bottom flask, and 200 mL of 1 mol / L sodium hydroxide solution was added. The mixture was reacted at room temperature for 3 h. After the reaction, the resin microspheres were washed three times each with deionized water and methanol. Finally, the washed resin microspheres were dried in a vacuum drying oven at 50 °C for 8 h to obtain a porous crosslinked quaternary ammonium base resin β-H elimination promoter with a quaternary ammonium base exchange capacity of 3.8 mmol / g.
[0033] Example 2
[0034] In a 250 mL round-bottom flask, 20 g of chloromethylated polystyrene crosslinking resin, 10 g of triethylamine, and 200 mL of anhydrous acetonitrile were added sequentially. The mixture was stirred thoroughly and heated to 110 °C under reflux for 15 h. The reaction was then stopped and cooled to room temperature. The triethylamine and acetonitrile solvents were separated by filtration using a Buchner funnel. Simultaneously, the resin microspheres were washed with methanol to remove residual triethylamine and acetonitrile. The washed resin microspheres were then placed in a vacuum oven and dried at 50 °C for 6 h to remove excess methanol. 20 g of the resin microspheres were then transferred to a 500 mL round-bottom flask, and 200 mL of 1 mol / L sodium hydroxide solution was added. The mixture was reacted at room temperature for 5 h. After the reaction, the resin microspheres were washed three times each with deionized water and methanol. Finally, the washed resin microspheres were placed in a vacuum drying oven and dried at 50 °C for 8 h to obtain a porous crosslinked quaternary ammonium base resin β-H elimination promoter with a quaternary ammonium base exchange capacity of 4.1 mmol / g.
[0035] Example 3
[0036] In a 250 mL round-bottom flask, 20 g of chloromethylated polystyrene crosslinking resin, 14 g of triethylamine, and 200 mL of anhydrous acetonitrile were added sequentially. The mixture was stirred thoroughly and heated to 110 °C under reflux for 15 h. The reaction was then stopped and cooled to room temperature. The triethylamine and acetonitrile solvents were separated by filtration using a Buchner funnel. Simultaneously, the resin microspheres were washed with methanol to remove residual triethylamine and acetonitrile. The washed resin microspheres were then placed in a vacuum oven and dried at 50 °C for 6 h to remove excess methanol. 20 g of resin microspheres were then transferred to a 500 mL round-bottom flask, and 200 mL of 1 mol / L sodium hydroxide solution was added. The mixture was reacted at room temperature for 8 h. After the reaction, the resin microspheres were washed three times each with deionized water and methanol. Finally, the washed resin microspheres were placed in a vacuum drying oven and dried at 50 °C for 8 h to obtain a porous crosslinked quaternary ammonium base resin β-H elimination promoter with a quaternary ammonium base exchange capacity of 4.4 mmol / g.
[0037] Example 4
[0038] In a 250 mL round-bottom flask, 20 g of chloromethylated polystyrene crosslinking resin, 14 g of triethylamine, and 200 mL of anhydrous acetonitrile were added sequentially. The mixture was stirred thoroughly and refluxed at 110 °C for 15 h. The reaction was then stopped and cooled to room temperature. The triethylamine and acetonitrile solvents were separated by filtration using a Buchner funnel. Simultaneously, the resin microspheres were washed with methanol to remove residual triethylamine and acetonitrile. The washed resin microspheres were then dried in a vacuum oven at 50 °C for 6 h to remove excess methanol. 20 g of resin microspheres were then transferred to a 500 mL round-bottom flask, and 250 mL of 1 mol / L sodium hydroxide solution was added. The mixture was reacted at room temperature for 8 h. After the reaction, the resin microspheres were washed three times each with deionized water and methanol. Finally, the washed resin microspheres were dried in a vacuum drying oven at 50 °C for 8 h to obtain a porous crosslinked quaternary ammonium base resin β-H elimination promoter with a quaternary ammonium base exchange capacity of 4.6 mmol / g.
[0039] Example 5
[0040] In a 250 mL round-bottom flask, 20 g of chloromethylated polystyrene crosslinking resin, 14 g of triethylamine, and 200 mL of anhydrous acetonitrile were added sequentially. The mixture was stirred thoroughly and refluxed at 110 °C for 15 h. The reaction was then stopped and cooled to room temperature. The triethylamine and acetonitrile solvents were separated by filtration using a Buchner funnel. Simultaneously, the resin microspheres were washed with methanol to remove residual triethylamine and acetonitrile. The washed resin microspheres were then dried in a vacuum oven at 50 °C for 6 h to remove excess methanol. 20 g of the resin microspheres were then transferred to a 500 mL round-bottom flask, and 300 mL of 1 mol / L sodium hydroxide solution was added. The mixture was reacted at room temperature for 8 h. After the reaction, the resin microspheres were washed three times each with deionized water and methanol. Finally, the washed resin microspheres were dried in a vacuum drying oven at 50 °C for 8 h to obtain a porous crosslinked quaternary ammonium base resin β-H elimination promoter with a quaternary ammonium base exchange capacity of 4.7 mmol / g.
[0041] Example 6
[0042] In a 250 mL round-bottom flask, 20 g of chloromethylated polystyrene crosslinking resin, 14 g of triethylamine, and 200 mL of anhydrous acetonitrile were added sequentially. The mixture was stirred thoroughly and heated to 110 °C under reflux for 15 h. The reaction was then stopped and cooled to room temperature. The triethylamine and acetonitrile solvents were separated by filtration using a Buchner funnel. Simultaneously, the resin microspheres were washed with methanol to remove residual triethylamine and acetonitrile. The washed resin microspheres were then placed in a vacuum oven and dried at 50 °C for 6 h to remove excess methanol. 20 g of the resin microspheres were then transferred to a 500 mL round-bottom flask, and 300 mL of 1 mol / L sodium hydroxide solution was added. The mixture was reacted at room temperature for 8 h. After the reaction, the resin microspheres were washed three times each with deionized water and methanol. Finally, the washed resin microspheres were placed in a vacuum drying oven and dried at 70 °C for 9 h to obtain a porous crosslinked quaternary ammonium base resin β-H elimination promoter with a quaternary ammonium base exchange capacity of 4.5 mmol / g.
[0043] Examples 7-13
[0044] In a 150 mL high-pressure reactor, under nitrogen protection, 0.1 mmol of a metal compound, 0.1 mmol of bisphosphine ligand, 10 mmol of β-H elimination promoter, and 35 mL of solvent were added sequentially. The reactor was sealed, and the gas inside was replaced with carbon dioxide three times. Carbon dioxide was then introduced until the reactor pressure reached 1 MPa, followed by the introduction of ethylene until the reactor pressure reached 5 MPa. The temperature was slowly increased to 80 °C under temperature control, and the reaction was carried out for 12 h. After cooling to room temperature, the reactor was removed, and the β-H elimination promoter was filtered. The filtered resin microspheres were regenerated with 1 mol / L sodium hydroxide solution, and the resulting liquid was analyzed. The raw materials and reaction parameters for Examples 7-13 are shown in Table 1.
[0045] Table 1. Raw materials and reaction-related parameters for Examples 7-13
[0046]
[0047] Examples 14-18
[0048] In a 150 mL high-pressure reactor, under nitrogen protection, 0.1 mmol of bis-(1,5-cyclooctadiene)nickel, 1,2-bis(dicyclohexylphosphine)ethane, β-H elimination promoter, and 35 mL of THF were added sequentially. The reactor was sealed, and the gas inside was replaced with carbon dioxide three times. Carbon dioxide was then introduced until the reactor pressure reached 1 MPa, followed by the introduction of ethylene until the reactor pressure reached 5 MPa. The temperature was slowly increased to 80 °C under temperature control, and the reaction was carried out for 12 h. After cooling to room temperature, the reactor was removed, and the β-H elimination promoter was filtered. The filtered resin microspheres were regenerated with 1 mol / L sodium hydroxide solution, and the resulting liquid was analyzed. The raw materials and reaction parameters for Examples 14-18 are shown in Table 2.
[0049] Table 2. Raw materials and reaction-related parameters for Examples 14-18
[0050]
[0051] Examples 19-22
[0052] In a 150 mL high-pressure reactor, under nitrogen protection, 0.1 mmol of bis-(1,5-cyclooctadiene)nickel, 0.2 mmol of 1,2-bis(dicyclohexylphosphine)ethane, 40 mmol of β-H elimination promoter, and 35 mL of THF were added sequentially. The reactor was sealed, and the gas inside was replaced with carbon dioxide three times. Carbon dioxide was then introduced until the reactor pressure reached 1 MPa, followed by the introduction of ethylene until the reactor pressure reached 5 MPa. The temperature was slowly increased to the set temperature and the reaction time was set using a temperature controller. After the reaction was completed, the reactor was cooled to room temperature, and the reactor was removed. The β-H elimination promoter was filtered, and the filtered resin microspheres were regenerated with a 1 mol / L sodium hydroxide solution. The resulting liquid was then analyzed. The raw materials and reaction parameters for Examples 19-22 are shown in Table 3.
[0053] Table 3. Raw materials and reaction-related parameters for Examples 19-22
[0054]
[0055] Comparative Examples 1-3
[0056] In a 150 mL high-pressure reactor, under nitrogen protection, 0.1 mmol of bis-(1,5-cyclooctadiene)nickel, 0.2 mmol of 1,2-bis(dicyclohexylphosphine)ethane, 40 mmol of β-H elimination promoter, and 35 mL of THF were added sequentially. The reactor was sealed, and the gas inside was replaced with carbon dioxide three times. Carbon dioxide was then introduced until the reactor pressure reached 1 MPa, followed by the addition of ethylene until the pressure reached 5 MPa. The temperature was slowly increased to 80 °C using a temperature controller, and the reaction was carried out for 15 h. After cooling to room temperature, the reactor was removed, and the β-H elimination promoter was filtered. The filtered resin microspheres were regenerated with 1 mol / L sodium hydroxide solution, and the resulting liquid was analyzed. The raw materials and reaction parameters for Comparative Examples 1-3 are shown in Table 4.
[0057] Table 4. Raw materials and reaction-related parameters for Comparative Examples 1-3
[0058]
[0059] Compared with the three β-H elimination promoters used in Comparative Examples 1-3, the quaternary ammonium base in the porous crosslinked quaternary ammonium base resin β-H elimination promoter of the present invention has a stronger basicity than that of general sodium carboxylate and sodium phenolate. After the reaction is completed, the resin microspheres are filtered out and regenerated with 1 mol / L sodium hydroxide solution, so that the quaternary ammonium base resin can be obtained again. At the same time, the sodium acrylate product generated by the reaction can be obtained in the aqueous phase, which simplifies the resin regeneration process and reduces the energy consumption for product separation.
Claims
1. A method for preparing a porous cross-linked quaternary ammonium alkali resin β-H elimination promoter, characterized in that, Includes the following steps: S1 chloromethylated polystyrene crosslinked resin and triethylamine were stirred and heated under reflux in acetonitrile solvent; S2 filtration removes acetonitrile and residual triethylamine, followed by washing with methanol to remove residual triethylamine and acetonitrile from the resin microspheres. S3 dried the washed resin microspheres to remove excess methanol, then reacted them with sodium hydroxide solution at room temperature for 3-8 hours. After the reaction was completed, the resin microspheres were washed with water and methanol respectively, and finally dried to obtain porous cross-linked quaternary ammonium base resin β-H elimination promoter.
2. The preparation method of the porous crosslinked quaternary ammonium alkali resin β-H elimination promoter as described in claim 1, characterized in that, In step S1, the amount of triethylamine added is 30-45% of the total mass of chloromethylated polystyrene crosslinking resin and triethylamine.
3. The preparation method of the porous crosslinked quaternary ammonium base resin β-H elimination promoter as described in claim 1, characterized in that, In step S1, the reflux reaction temperature is 90-110℃ and the reflux reaction time is 10-15h.
4. The preparation method of the porous crosslinked quaternary ammonium alkali resin β-H elimination promoter as described in claim 1, characterized in that, In step S3, the concentration of the sodium hydroxide solution is 1 mol / L; the amount of sodium hydroxide added is 40-60% of the mass of the resin microspheres.
5. The preparation method of the porous crosslinked quaternary ammonium base resin β-H elimination promoter as described in claim 1, characterized in that, In step S3, the amount of sodium hydroxide added is 60% of the mass of the resin microspheres.
6. The preparation method of the porous crosslinked quaternary ammonium alkali resin β-H elimination promoter as described in claim 1, characterized in that, In step S3, the drying temperature is 50-70℃ and the drying time is 7-9h.
7. The porous crosslinked quaternary ammonium alkali resin β-H elimination promoter prepared by the preparation method according to any one of claims 1-6.
8. The application of the porous crosslinked quaternary ammonium alkali resin β-H elimination promoter as described in claim 7, characterized in that, Ethylene and carbon dioxide react to form acrylic acid under the catalysis of a catalyst composed of palladium or nickel compounds, phosphine ligands, and porous cross-linked quaternary ammonium base resin β-H elimination promoter.
9. The application of the porous cross-linked quaternary ammonium alkali resin β-H elimination promoter as described in claim 8, characterized in that, The nickel compound is bis-(1,5-cyclooctadiene)nickel, and the palladium compound is tetratetriphenylphosphine palladium; the phosphine ligand is a bidentate phosphine ligand, preferably 1,2-bis(dicyclohexylphosphine)ethane or 1,4-bis(dicyclohexylphosphine)propane; the molar ratio of the palladium or nickel compound, the phosphine ligand, and the porous crosslinked benzyl alcohol resin metal salt β-H elimination promoter is 1:(1-2):(100-600).
10. The application of the porous crosslinked quaternary ammonium base resin β-H elimination promoter as described in claim 8, characterized in that, The reaction temperature is 60-90℃ and the reaction time is 12-24h; preferably, the reaction temperature is 70-80℃ and the reaction time is 15-20h.