Method for synthesizing methyl methacrylate by using metal matrix and carbon material catalyst
By using metal-based @carbon material catalysts for the esterification reaction, the problems of small scale, heavy pollution and large safety hazards in the traditional methyl methacrylate production methods are solved, and efficient and environmentally friendly methyl methacrylate synthesis is achieved.
Patent Information
- Application Number
- CN202411551377.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-01
- Publication Date
- 2025-03-18
AI Technical Summary
The traditional methyl methacrylate production methods have problems such as small scale, heavy pollution, and great safety hazards, and are difficult to meet market demand.
The methyl methacrylate was synthesized by an esterification reaction using a metal-based @carbon material catalyst, including preparing the catalyst material under high temperature inert environments and conducting the esterification reaction in a sealed reactor.
It improves the stability of the material, accelerates the esterification reaction rate, and improves the formation rate of methyl methacrylate. It has the advantages of environmentally friendly, low production costs and wide range of raw materials.
Smart Images
Figure CN119638573A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of organic synthesis, and in particular to a method for synthesizing methyl methacrylate using a metal-based carbon material catalyst. Background Art
[0002] With the rapid development of the global chemical industry, the demand for high-performance polymers is growing. As a key chemical raw material, methyl methacrylate has attracted much attention due to its core role in the production of materials such as organic glass, special optical fibers, and high-end coatings. At present, the international annual demand for methyl methacrylate has exceeded 4 million tons, and my country's demand is about 700,000 tons, most of which rely on imports. Traditional methyl methacrylate production methods, such as the acetone cyanohydrin method, have problems such as small scale, heavy pollution, and great safety hazards. In addition, due to the limited supply of raw materials, it is difficult to meet market demand. Therefore, the development of a new, environmentally friendly, and efficient methyl methacrylate synthesis process has important industrial value and social benefits.
[0003] As basic chemical raw materials, the potential of methanol and methacrolein in the synthesis of methyl methacrylate has not been fully explored. As a widely available carbon-one resource, the application research of methanol in synthetic chemistry is of great significance. As a key intermediate in the production of methyl methacrylate, the innovation of methacrolein's synthesis method has a driving effect on the development of the entire industrial chain. The efficient synthesis of methyl methacrylate can be achieved through catalytic oxidation and esterification reactions, which will help promote the green synthesis and sustainable development of related chemicals. Summary of the invention
[0004] The present invention provides a method for synthesizing methyl methacrylate using a metal-based carbon material catalyst, comprising the following steps:
[0005] Firstly, a metal-based @ carbon material catalyst material is obtained by using a precursor carrier in a high-temperature inert environment; then the catalyst material, anhydrous methanol and methacrolein are loaded into a sealed reactor, vented and oxygenated, and the temperature is raised to 60-100°C for esterification reaction for 1-5 hours. After the esterification reaction is completed, methyl methacrylate is obtained by cooling in an ice bath and centrifuging.
[0006] Preferably, the precursor carrier is a sponge rich in nitrogen, such as melamine sponge.
[0007] Preferably, the metal base is a transition metal salt comprising copper, tin, nickel or cobalt.
[0008] Preferably, the high temperature inert environment is an argon or nitrogen atmosphere at a temperature of 500 to 800°C.
[0009] Preferably, the molar ratio of anhydrous methanol to methacrolein is 20:1.
[0010] Preferably, the mass of the catalyst material feed accounts for 1.0% to 2.0% of the total mass of the reactant system.
[0011] Preferably, the exhaust and oxygenation step is to close the vent valve of the reactor - fill in oxygen - close the oxygen inlet valve, and repeat the charging and discharging three times to eliminate the original air in the reaction device.
[0012] Preferably, the temperature of the esterification reaction is 60-100° C., and the reaction time is 1-5 hours.
[0013] Preferably, the ice bath cooling means taking out the reaction kettle after the reaction is completed and quickly placing it in an ice water bath to cool it to about 10°C.
[0014] Preferably, the centrifugal separation refers to transferring the reaction solution into a centrifuge tube and separating the reaction solution and the catalyst at 5000 rpm for 10 min.
[0015] On the basis of being in accordance with the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present invention.
[0016] Compared with the prior art, the present invention has the following beneficial effects:
[0017] The present invention can improve the stability of the material, accelerate the esterification reaction rate, and increase the production rate of methyl methacrylate by constructing a metal-based @ carbon material catalyst material; the present invention has the advantages of being environmentally friendly, low in production cost, and having a wide source of raw materials, and can improve production efficiency and product quality, and enhance the core competitiveness of the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 This is the X-ray diffraction pattern of the catalyst in Example 1 of the present invention.
[0019] Figure 2 This is a scanning electron microscope image of the catalyst in Example 2 of the present invention.
[0020] Figure 3 This is a scanning electron microscope image of the catalyst in Example 3 of the present invention.
[0021] Figure 4 It is a performance comparison chart of Examples 1-3 of the present invention and Comparative Examples 1-3. DETAILED DESCRIPTION
[0022] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but it should be understood that the protection scope of the present invention is not limited by the specific implementation methods.
[0023] The present invention provides a method for synthesizing methyl methacrylate with a metal-based carbon material catalyst, comprising the following steps:
[0024] First, a metal-based @ carbon material catalytic material is obtained by using a precursor carrier under a high-temperature inert environment; then the catalyst material, anhydrous methanol, and methacrolein are loaded into a sealed reactor, the exhaust is oxygenated, the temperature is raised to 60-100°C, and the esterification reaction is carried out for 1-5 hours. After the esterification reaction is completed, it is cooled in an ice bath and centrifuged to obtain methyl methacrylate. The precursor carrier is a sponge rich in nitrogen, such as melamine sponge. The metal base is a transition metal salt containing copper, tin, nickel, and cobalt. The high-temperature inert environment is an argon or nitrogen atmosphere at a temperature of 500-800°C. The molar ratio of anhydrous methanol and methacrolein is 20:1. The mass of the catalyst material feed accounts for 1.0% to 2.0% of the total mass of the reactant system. The exhaust and oxygenation steps are to close the reactor vent valve-fill oxygen-close the oxygen inlet valve, and repeat the charge and discharge three times to exclude the original air in the reaction device. The temperature of the esterification reaction is 60-100°C, and the reaction time is 1-5 hours. Ice bath cooling means taking out the reactor after the reaction is completed and quickly placing it in an ice water bath to cool it to about 10° C. Centrifugal separation means transferring the reaction solution to a centrifuge tube and separating it at 5000 rpm for 10 min to separate the reaction solution and the catalyst.
[0025] A. Preparation of catalytic materials: First, cut the nitrogen-rich macroporous sponge into appropriate sizes, then soak it in a 0.1-0.5 mol / L metal salt solution at a certain temperature and let it stand for 3-5 hours to ensure that the metal salt fully and evenly coats the sponge. Take out the resulting sponge and quickly freeze it with liquid nitrogen, and dry it in a vacuum freeze dryer for 20-40 hours to obtain a metal @ sponge precursor. Finally, the metal @ sponge precursor is calcined in an inert atmosphere at 500-800 ° C for 1-3 hours to obtain a metal-based @ carbon material composite catalyst material.
[0026] B. Esterification reaction process: Weigh 1-2g of metal-based @ carbon material catalyst and load it into a sealed reactor equipment, measure 50-100g of anhydrous methanol and 5-10g of methacrolein (98%) and pour them into the reactor (the molar ratio of methanol to methacrolein is 20:1). Then seal the reactor and connect the oxygen pipeline, repeatedly charge and discharge three times to remove the original air inside the reactor. Place the reactor under constant temperature conditions and react for 1-2 hours to end the reaction. Take out the reactor and quickly place it in an ice water bath to cool it down. Finally, centrifuge the reaction solution and analyze the product by gas chromatography.
[0027] Embodiment 1:
[0028] First, the nitrogen-rich macroporous melamine sponge (MS) was cut into a size of 3 cm × 3 cm × 3 cm, and then placed in a 0.2 mol / L tin tetrachloride solution at 60°C for 3 hours. The resulting melamine sponge was taken out and quickly frozen with liquid nitrogen, and dried in a vacuum freeze dryer for 30 hours to obtain the Sn@MS precursor. The precursor was calcined at 600°C in an argon atmosphere for 2 hours to obtain the Sn@NC composite catalyst material (X-ray diffraction pattern as shown in Figure 2). Figure 1 As shown). Weigh 1g of Sn@NC catalyst and load it into a sealed reactor. Measure 64g of anhydrous methanol and 7g of methacrolein (98%) and pour them into the reactor (the molar ratio of methanol to methacrolein is 20:1). Then seal the reactor, connect the oxygen pipeline, and repeatedly charge and discharge it three times to remove the original air inside the reactor. Place the reactor in a constant temperature water bath at 80°C for 2 hours. Take out the reactor and quickly place it in an ice water bath to cool it down. Finally, centrifuge the reaction solution. The reaction solution was analyzed by gas chromatography, and the results showed that the conversion rate and selectivity of methyl methacrylate were 83.6% and 96.5%, respectively.
[0029] Embodiment 2:
[0030] First, the nitrogen-rich macroporous melamine sponge (MS) was cut into a size of 3 cm × 3 cm × 3 cm, and then placed in a 0.25 mol / L tin tetrachloride solution at 80 ° C and allowed to stand for 2 hours. The resulting melamine sponge was taken out and quickly frozen with liquid nitrogen, and dried in a vacuum freeze dryer for 40 hours to obtain the Sn@MS precursor. The precursor was calcined in a nitrogen atmosphere at 700 ° C for 2 hours to obtain the Sn@NC composite catalyst material (morphology as shown in FIG. Figure 2 As shown). Weigh 1.5g of Sn@NC catalyst and load it into a sealed reactor. Measure 80g of anhydrous methanol and 8.75g of methacrolein (98%) and pour them into the reactor (the molar ratio of methanol to methacrolein is 20:1). Then seal the reactor, connect the oxygen pipeline, and repeatedly charge and discharge it three times to remove the original air inside the reactor. Place the reactor in a 60℃ constant temperature water bath for 2 hours. Take out the reactor and quickly place it in an ice water bath to cool it down. Finally, centrifuge the reaction solution. The reaction solution was analyzed by gas chromatography, and the results showed that the conversion rate and selectivity of methyl methacrylate were 85.2% and 96.8%, respectively.
[0031] Embodiment 3:
[0032] First, the nitrogen-rich macroporous melamine sponge (MS) was cut into a size of 3 cm × 3 cm × 3 cm, and then placed in a 0.25 mol / L tin tetrachloride solution at 80 ° C and allowed to stand for 2 hours. The resulting melamine sponge was taken out and quickly frozen with liquid nitrogen, and dried in a vacuum freeze dryer for 40 hours to obtain the Sn@MS precursor. The precursor was calcined in an argon atmosphere at 800 ° C for 2 hours to obtain the Sn@NC composite catalyst material (morphology as shown in FIG. Figure 3 As shown). Weigh 1.2g of Sn@NC catalyst and load it into a sealed reactor. Measure 70g of anhydrous methanol and 7.6g of methacrolein (98%) and pour them into the reactor (the molar ratio of methanol to methacrolein is 20:1). Then seal the reactor, connect the oxygen pipeline, and repeatedly charge and discharge it three times to remove the original air inside the reactor. Place the reactor in a 60℃ constant temperature water bath for 2 hours. Take out the reactor and quickly place it in an ice water bath to cool it down. Finally, centrifuge the reaction solution. The reaction solution was analyzed by gas chromatography, and the results showed that the conversion rate and selectivity of methyl methacrylate were 82.1% and 94.4%, respectively.
[0033] Comparative Example 1
[0034] Compared with Example 1, the difference is that the metal source is replaced by nickel chloride from tin tetrachloride, and the rest is consistent with Example 1. The conversion rate and selectivity of the prepared Ni@NC catalyst material to methyl methacrylate are 75.9% and 93.4%, respectively.
[0035] Comparative Example 2
[0036] Compared with Example 2, the difference is that the tin tetrachloride solution is replaced with a cobalt chloride solution, and the rest is consistent with Example 2. The conversion rate and selectivity of the prepared Co@NC catalyst material to methyl methacrylate are 60.3% and 76.4%, respectively.
[0037] Comparative Example 3
[0038] Compared with Example 3, the difference is that the tin tetrachloride solution is replaced by a cupric chloride solution, and the rest is consistent with Example 3. The conversion rate and selectivity of the prepared Cu@NC catalyst material to methyl methacrylate are 79.3% and 88.5%, respectively.
[0039] The performance comparison diagram of Examples 1-3 and Comparative Examples 1-3 is as follows Figure 4 shown.
[0040] According to the above embodiments, the synthesis of methyl methacrylate can be achieved, and the metal-based@carbon material catalyst prepared by the method can effectively improve the conversion rate and selectivity of methyl methacrylate, thereby achieving the purpose of the present invention.
Claims
1. A method for synthesizing methyl methacrylate using a metal-based@carbon material catalyst, characterized in that: The following steps are involved: Firstly, a metal-based @ carbon material catalyst material is obtained by using a precursor carrier in a high-temperature inert environment; then the catalyst material, anhydrous methanol and methacrolein are loaded into a sealed reactor, vented and oxygenated, and the temperature is raised to 60-100°C for esterification reaction for 1-5 hours. After the esterification reaction is completed, methyl methacrylate is obtained by cooling in an ice bath and centrifuging.
2. The method for synthesizing methyl methacrylate using a metal-based@carbon material catalyst according to claim 1, characterized in that: The precursor carrier is a sponge rich in nitrogen.
3. The method for synthesizing methyl methacrylate using a metal-based@carbon material catalyst according to claim 1, characterized in that: The metal base is a transition metal salt comprising copper, tin, nickel and cobalt.
4. The method for synthesizing methyl methacrylate using a metal-based@carbon material catalyst according to claim 1, characterized in that: The high temperature inert environment is an argon or nitrogen atmosphere at a temperature of 500 to 800°C.
5. The method for synthesizing methyl methacrylate using a metal-based@carbon material catalyst according to claim 1, characterized in that: The molar ratio of anhydrous methanol to methacrolein is 20:
1.
6. The method for synthesizing methyl methacrylate using a metal-based@carbon material catalyst according to claim 1, characterized in that: The mass of the catalyst material feed accounts for 1.0% to 2.0% of the total mass of the reactant system.
7. The method for synthesizing methyl methacrylate using a metal-based@carbon material catalyst according to claim 1, characterized in that: The exhaust and oxygenation steps are as follows: closing the vent valve of the reactor - filling in oxygen - closing the oxygen inlet valve, repeating the process three times to remove the original air in the reaction device.
8. The method for synthesizing methyl methacrylate using a metal-based@carbon material catalyst according to claim 1, characterized in that: The temperature of the esterification reaction is 60-100° C., and the reaction time is 1-5 hours.
9. The method for synthesizing methyl methacrylate using a metal-based@carbon material catalyst according to claim 1, characterized in that: The ice bath cooling means taking out the reactor after the reaction is completed and quickly placing it in an ice water bath to cool it to about 10°C.
10. The method for synthesizing methyl methacrylate using a metal-based@carbon material catalyst according to claim 1, characterized in that: The centrifugal separation refers to transferring the reaction solution into a centrifuge tube and separating the reaction solution and the catalyst at 5000 rpm for 10 minutes.