A copper-based nitrogen-rich organic polymer catalytic material, a preparation method and application thereof
By using copper-based nitrogen-rich organic polymer catalytic materials, the problems of low conversion efficiency and poor tolerance of low-concentration CO2 have been solved, achieving efficient adsorption and catalytic conversion to generate oxazolidinone compounds with good stability and impurity tolerance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- GUILIN UNIV OF ELECTRONIC TECH
- Filing Date
- 2026-03-11
- Publication Date
- 2026-06-09
AI Technical Summary
Existing catalytic systems are difficult to efficiently convert low-concentration carbon dioxide and have poor tolerance to impurity gases in flue gas, resulting in low mass transfer efficiency, easy catalyst deactivation, and high cost.
A copper-based nitrogen-rich organic polymer catalyst was developed. Monomers were screened using density functional theory calculations to construct a high-nitrogen-content organic polymer framework, which was then loaded with copper active components to form a Cu@TPT-Trz-POP catalyst, enabling efficient adsorption and catalytic conversion of low-concentration CO2.
It significantly improves adsorption capacity and catalytic efficiency under low CO2 conditions, with a yield of 90% for generating oxazolidinone compounds. It exhibits good tolerance to impurities in flue gas, excellent recyclability, and has potential for industrial applications.
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Figure CN122164493A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of catalytic materials and carbon dioxide resource utilization technology, specifically relating to a copper-based nitrogen-rich organic polymer catalytic material, its preparation method, and its application. Background Technology
[0002] Carbon capture, utilization, and storage (CCUS) is a key technological pathway for achieving low-carbon industrial transformation. Among these, the catalytic conversion of carbon dioxide (CO2) into high-value-added chemicals is central to its resource utilization. However, existing catalytic systems largely rely on high-concentration CO2, leading to high energy consumption and costs in the capture stage. Direct conversion from low-concentration CO2 sources such as flue gas and air (e.g., 5-30 vol.%) presents significant technological challenges due to low CO2 concentrations and interference from impurity gases, resulting in low mass transfer efficiency, strong competitive adsorption, and easy catalyst deactivation. Therefore, developing catalytic materials with both strong adsorption and high activation capabilities is crucial.
[0003] Nitrogen-enriched polymer materials, due to their high-density nitrogen-active sites (such as triazine and triazole) in their backbone, can achieve highly efficient and selective enrichment of CO2 and can stably support metal active centers, providing a possibility for constructing integrated "adsorption-catalysis" materials. In existing technologies, such as the copper-based materials reported by Rao et al. N While heterocyclic carbene porous polymer catalysts (Cu@NHC-1) and porous organic polymer-supported silver oxide composites (POPs-n@Ag2O) reported by Xia et al. have made progress in the conversion of medium-concentration CO2, their catalytic performance still needs breakthroughs when dealing with lower concentrations (e.g., 5 vol.%) of gas sources. Furthermore, the development of traditional catalysts largely relies on trial and error, resulting in low efficiency and high costs.
[0004] Therefore, developing a novel catalytic material that can efficiently convert low-concentration CO2 and has excellent stability and impurity tolerance, and establishing an efficient catalyst design method are technical problems that urgently need to be solved in this field. Summary of the Invention
[0005] To address the shortcomings of existing technologies, the present invention aims to provide a copper-based nitrogen-rich organic polymer catalytic material, its preparation method, and its applications. This catalytic material is designed based on density functional theory (DFT) calculations to drive the screening of dominant monomers, enabling efficient adsorption and catalytic conversion of low-concentration CO2.
[0006] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a copper-based nitrogen-rich organic polymer catalytic material, wherein the catalytic material uses the nitrogen-rich organic polymer TPT-Trz-POP as a support and loads copper active components thereon. The nitrogen-rich organic polymer TPT-Trz-POP is prepared by a Schiff base condensation reaction of 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine (denoted as TPT-CHO or monomer S1) and 3,5-diamino-1,2,4-triazole (denoted as Trz-NH2 or monomer S2).
[0007] As a preferred embodiment, the copper active component includes Cu(I) and Cu(II), with Cu(I) being the predominant component.
[0008] As a preferred embodiment, the copper content in the catalytic material is 5-12% by mass, for example, 8.02%.
[0009] In a second aspect, the present invention provides a method for preparing the copper-based nitrogen-rich organic polymer catalytic material described in the first aspect, comprising the following steps: S1. 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine and 3,5-diamino-1,2,4-triazole were subjected to Schiff base condensation reaction in an organic solvent to obtain the nitrogen-rich organic polymer TPT-Trz-POP. S2. Disperse the TPT-Trz-POP obtained in step S1 in water, add copper source solution, and carry out the reaction; S3. Add a reducing agent to the reaction system of step S2 to carry out a reduction reaction. After the reaction is completed, perform post-processing to obtain the copper-based nitrogen-rich organic polymer catalytic material.
[0010] As a preferred embodiment, in step S1, the molar ratio of 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine to 3,5-diamino-1,2,4-triazole is 2:3; The organic solvent is a mixture of mesitylene and tetrahydrofuran; The condensation reaction is carried out at a temperature of 80-120℃ for a time of 48-96 hours.
[0011] As a preferred embodiment, in step S2, the copper source is copper acetate; The mass ratio of the TPT-Trz-POP to the copper source is 10:1; The reaction is carried out at a temperature of 60-100℃ for a time of 0.5-2 hours.
[0012] As a preferred embodiment, in step S3, the reducing agent is hydrazine hydrate; the temperature of the reduction reaction is 60-100℃, and the time is 1-3h; the post-treatment includes filtration, washing, and drying.
[0013] Thirdly, the present invention provides the application of the copper-based nitrogen-rich organic polymer catalytic material described in the first aspect above or the copper-based nitrogen-rich organic polymer catalytic material prepared by the preparation method described in the second aspect above in the catalytic conversion of low-concentration carbon dioxide.
[0014] As a preferred embodiment, the volume concentration of the low-concentration carbon dioxide is 1-15%, preferably 5%; The process involves reacting low-concentration carbon dioxide with propargylamine compounds via a carboxylation-cyclization reaction to generate oxazolidinone compounds.
[0015] As a preferred embodiment, the carboxylation-cyclization reaction is carried out under the following conditions: using the copper-based nitrogen-rich organic polymer catalytic material as a catalyst, the reaction is carried out in a polar solvent (such as DMSO) in the presence of an alkali (such as DBU); wherein the reaction temperature is 20-40℃ and the reaction time is 12-24h.
[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. Novel Material Structure: This invention utilizes DFT calculations to screen specific nitrogen-rich monomers (TPT-CHO and Trz-NH2) with optimal CO2 adsorption and activation potential as building blocks. Through Schiff base condensation reactions, a high-nitrogen-content (up to 44%) organic polymer framework was successfully constructed. This framework provides an ideal platform for CO2 enrichment and catalytic conversion.
[0017] 2. Excellent performance: The Cu@TPT-Trz-POP catalytic material prepared in this invention exhibits significant solvent-induced dynamic response characteristics under a low-concentration CO2 atmosphere (5 vol.%), resulting in a substantial increase in adsorption capacity. Under mild conditions (30°C, 0.1 MPa), the yield of cyclooxygenated propargylamine reacting with low-concentration CO2 to form oxazolidinone compounds can reach up to 90%.
[0018] 3. Good stability: This catalytic material has good recyclability. After 11 cycles, the catalytic activity did not decrease significantly. It also shows good tolerance to common SO2 and NO2 impurities in flue gas, and has potential for industrial application.
[0019] 4. Advanced design strategy: The "computation-driven and dynamic structure regulation strategy" proposed in this invention provides a new and generalizable theoretical framework and design idea for developing catalytic materials for efficient conversion of low-concentration CO2. Attached Figure Description
[0020] Figure 1 The synthesis path diagram of Cu@TPT-Trz-POP in the example is shown.
[0021] Figure 2This is a schematic diagram illustrating the preparation method of monomer S1 (2,4,6-tris(4-formylphenoxy)-1,3,5-triazine) in the examples.
[0022] Figure 3 The thermogravimetric analysis (TGA) test results for Cu@TPT-Trz-POP in this example are shown.
[0023] Figure 4 The image shows the X-ray photoelectron spectroscopy (XPS) spectrum of Cu@TPT-Trz-POP in the example. (a) is the full spectrum, (b) is the O 1s spectrum, (c) is the N 1s spectrum, and (d) is the Cu 2p spectrum.
[0024] Figure 5 The images shown are scanning electron microscope (SEM) images of Cu@TPT-Trz-POP before and after its use in this example.
[0025] Figure 6 The images shown are transmission electron microscope (TEM) images and elemental mapping diagrams of Cu@TPT-Trz-POP before and after its use in this embodiment.
[0026] Figure 7 The image shows the in-situ Raman spectrum of Cu@TPT-Trz-POP in the example.
[0027] Figure 8 The solid-state carbon NMR spectrum of Cu@TPT-Trz-POP in the examples ( 13 (C NMR) diagram.
[0028] Figure 9 The equation for the carboxylation and cyclization reaction of propargylamine with CO2 catalyzed by Cu@TPT-Trz-POP in the examples is shown.
[0029] Figure 10 The figure shows the results of condition optimization for the catalytic reaction in the examples.
[0030] Figure 11 The diagram shows the kinetics and leaching experiments under 5 vol.% CO2 conditions in this embodiment.
[0031] Figure 12 This is a diagram illustrating the cyclical effect of Cu@TPT-Trz-POP in the example.
[0032] Figure 13 The results of the cyclization reaction of different types of propargylamine with 5 vol.% CO2 are shown in the examples. Detailed Implementation
[0033] The present invention will be further described in detail below with reference to specific embodiments and accompanying drawings. These embodiments are for illustrative purposes only and do not constitute a limitation on the scope of protection of the present invention. Unless otherwise specified, the reagents and raw materials used in the present invention are all commercially available conventional products.
[0034] Example 1: DFT theoretical calculation to screen for advantageous building blocks The geometry of 10 candidate monomers was optimized using the ORCA 6.0.0 software package at the theoretical level of RIB3LYP-D3(BJ) / def2-TZVP(-f). Electrostatic potential (ESP) and inter-interaction region index (IRI) analysis were performed using the Multiwfn 3.8(dev) program. Preferred monomers were screened by calculating the adsorption energy of the monomers with CO2 and the change in bond angle of CO2 after adsorption. The results showed that TPT-CHO (aldehyde) had an adsorption energy of -30.88 kcal / mol for CO2, inducing a CO2 bond angle bend to 178.32°; Trz-NH2 (amino) had an adsorption energy of -6.21 kcal / mol for CO2, inducing a CO2 bond angle bend to 175.45°. Both exhibited the best performance within their respective categories. Therefore, TPT-CHO and Trz-NH2 were determined as the core building blocks for constructing the catalyst framework.
[0035] Example 2: Synthesis of monomer S1 (2,4,6-tris(4-formylphenoxy)-1,3,5-triazine) Reference Figure 2 1.6 g of sodium hydroxide and 4.88 g of p-hydroxybenzaldehyde were dissolved in 50 mL of ultrapure water and stirred until dissolved. Then, a solution of 1.84 g of cyanuric chloride and 0.02 g of tetrabutylammonium bromide dissolved in 50 mL of dichloromethane was added. The mixture was stirred overnight at room temperature. After the reaction was complete, the mixture was extracted with dichloromethane, and the organic phase was dried over anhydrous sodium sulfate and the solvent was removed under reduced pressure. The resulting crude solid product was washed successively with 10% NaOH solution and deionized water, and dried under vacuum at 60 °C to obtain monomer S1. Its structure was confirmed by 1H NMR spectroscopy.
[0036] Example 3: Synthesis of nitrogen-rich organic polymer TPT-Trz-POP The monomer S1 (890 mg, 2 mmol) obtained in Example 2 and 3,5-diamino-1,2,4-triazole (300 mg, 3 mmol) were added to 2 mL of mesitylene and 1 mL of tetrahydrofuran, and reacted at 100 °C for 72 hours. After the reaction was completed, the resulting solid precipitate was washed three times with methanol and chloroform, respectively, and dried under vacuum to obtain TPT-Trz-POP, which was then ground for later use.
[0037] Example 4: Synthesis of copper-based nitrogen-rich organic polymer Cu@TPT-Trz-POP Reference Figure 1 500 mg of TPT-Trz-POP prepared in Example 3 was ultrasonically dispersed in 100 mL of deionized water. 50 mg of copper acetate was dissolved in 3 mL of deionized water and added dropwise to the dispersion. After stirring at 80°C for 1 hour, the mixture was cooled to room temperature. 500 μL of hydrazine hydrate was added to the reaction mixture, and stirring was continued at 80°C for 2 hours. After the reaction was complete, the mixture was filtered, and the resulting solid product was washed successively with deionized water and anhydrous ethanol, dried under vacuum, and ground to obtain Cu@TPT-Trz-POP. The copper content was determined to be 8.02 wt% by flame atomic absorption spectrometry.
[0038] Example 5: Characterization of Catalytic Materials The Cu@TPT-Trz-POP prepared in Example 4 was characterized in various ways: Thermogravimetric analysis (TGA) Figure 3 This indicates that the material has good thermal stability below 300℃; XPS analysis ( Figure 4 This confirmed the presence of C, N, O, and Cu elements in the material, with copper mainly existing in the form of Cu(I). SEM and TEM Figure 5 , Figure 6 The material exhibits a layered stacked structure, with copper elements uniformly distributed within the polymer framework, and its morphology remains largely unchanged before and after use. In-situ Raman spectroscopy ( Figure 7 The data shows that, under a CO2 atmosphere, the material reaches a temperature of 2211 cm⁻¹. -1 The appearance of a new absorption peak at this point proves that it has an activating effect on CO2; solid 13 C NMR ( Figure 8 The successful construction of the polymer skeleton was confirmed.
[0039] Example 6: Optimization of conditions for catalytic conversion of low-concentration CO2 The reaction was carried out using the carboxylation-cyclization of propargylamine (1a) with 5 vol.% CO2 to produce oxazolidinone (2a) as a template. Figure 9 The effects of various factors on catalytic performance were investigated. Cu@TPT-Trz-POP catalyst was added to a 10 mL reaction tube. After purging the atmosphere, substrate 1a (0.25 mmol), base, and solvent were added, and the reaction was carried out at a specific temperature. The yield was determined by liquid chromatography.
[0040] Optimization results ( Figure 10The results showed that the optimal reaction conditions were: 40 mg catalyst, 0.25 mmol substrate 1a, 0.0125 mmol base DBU, 1 mL solvent DMSO, reaction temperature 30℃, and reaction time 18 h, under which the yield could reach 90%.
[0041] Example 7: Catalyst Recycling Performance Test The recyclability of a catalytic system is a core indicator for evaluating its practicality. Continuous monitoring confirmed that removing the catalyst after 4 hours of reaction operation immediately stopped the reaction, demonstrating that the catalytic process is heterogeneous catalysis (see...). Figure 11 The reaction was carried out under the optimal reaction conditions of Example 6. After the reaction was completed, the catalyst was separated by centrifugation, washed three times with anhydrous methanol and ethyl acetate, dried under vacuum, and then the next reaction was carried out under the same conditions. Results ( Figure 12 The results showed that the yield did not decrease significantly after the catalyst was recycled 11 times, demonstrating excellent cycle stability.
[0042] Example 8: Substrate Suitability Study Under the optimal reaction conditions determined in Example 6, cyclization reactions were carried out using different types of propargylamine substrates with 5 vol.% CO2. The optimal reaction conditions were: substrate (0.25 mmol), Cu@TPT-Trz-POP (40 mg), DMSO (1 mL), DBU (0.0125 mmol), temperature 30 °C, and reaction time 18 h.
[0043] result( Figure 13 The display shows that all those with N- Benzyl-terminated propargylamines were successfully converted to the corresponding oxazolidinone products (2a-2i). Substitution of the benzene ring with electron-withdrawing or electron-donating groups yielded the corresponding products in excellent yields. Alkyl-substituted terminal alkynes were reacted to yield the corresponding products in moderate yields (2e). Various terminal propargylamines containing different substituents were converted to the corresponding oxazolidinone products in good to excellent yields (72-92%), indicating that this catalytic system has good substrate versatility.
[0044] Example 9: Gram-scale Scale-up Reaction Under optimal reaction conditions, the amount of substrate 1a was scaled up to the gram level and reacted with 5 vol.% CO2. The target product 2a was obtained in 88% yield, indicating that this catalytic system has good potential for practical application.
[0045] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A copper-based nitrogen-rich organic polymer catalytic material, characterized in that, The catalytic material uses the nitrogen-rich organic polymer TPT-Trz-POP as a support, on which copper active components are loaded. The nitrogen-rich organic polymer TPT-Trz-POP was prepared by Schiff base condensation reaction of 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine and 3,5-diamino-1,2,4-triazole.
2. The copper-based nitrogen-rich organic polymer catalytic material according to claim 1, characterized in that, The copper active components include Cu(I) and Cu(II).
3. The copper-based nitrogen-rich organic polymer catalytic material according to claim 1 or 2, characterized in that, The catalytic material contains 5-12% copper by mass.
4. A method for preparing the copper-based nitrogen-rich organic polymer catalytic material according to any one of claims 1-3, characterized in that, Includes the following steps: S1. 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine and 3,5-diamino-1,2,4-triazole were subjected to Schiff base condensation reaction in an organic solvent to obtain the nitrogen-rich organic polymer TPT-Trz-POP. S2. Disperse the TPT-Trz-POP obtained in step S1 in water, add copper source solution, and carry out the reaction; S3. Add a reducing agent to the reaction system of step S2 to carry out a reduction reaction. After the reaction is completed, perform post-processing to obtain the copper-based nitrogen-rich organic polymer catalytic material.
5. The preparation method according to claim 4, characterized in that, In step S1, the molar ratio of 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine to 3,5-diamino-1,2,4-triazole is 2:3; The organic solvent is a mixture of mesitylene and tetrahydrofuran; The condensation reaction is carried out at a temperature of 80-120℃ for a time of 48-96 hours.
6. The preparation method according to claim 4, characterized in that, In step S2, the copper source is copper acetate; the mass ratio of TPT-Trz-POP to the copper source is 10:1; the reaction temperature is 60-100℃ and the reaction time is 0.5-2h.
7. The preparation method according to claim 4, characterized in that, In step S3, the reducing agent is hydrazine hydrate; the temperature of the reduction reaction is 60-100℃, and the time is 1-3h; the post-treatment includes filtration, washing, and drying.
8. The application of the copper-based nitrogen-rich organic polymer catalytic material according to any one of claims 1-3 or the copper-based nitrogen-rich organic polymer catalytic material prepared by the preparation method according to any one of claims 4-7 in the catalytic conversion of low-concentration carbon dioxide.
9. The application according to claim 8, characterized in that, The volume concentration of the low-concentration carbon dioxide is 1-15%; the conversion involves reacting the low-concentration carbon dioxide with propargylamine compounds via a carboxylation-cyclization reaction to generate oxazolidinone compounds.
10. The application according to claim 9, characterized in that, The carboxylation-cyclization reaction is carried out under the following conditions: using the copper-based nitrogen-rich organic polymer catalytic material as a catalyst, the reaction is carried out in a polar solvent in the presence of an alkali; wherein the reaction temperature is 20-40℃ and the reaction time is 12-24h.