Preparation method of nano-catalyst for photocatalytic reduction of CO2 into ethylene
By preparing a composite nanocatalyst of silicon carbide and copper powder, the problem of efficiently catalyzing the reduction of CO2 to ethylene at low temperatures was solved, achieving high yield and large-scale production, and breaking through the equipment and cost limitations of traditional methods.
Patent Information
- Application Number
- CN202510850827.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-24
- Publication Date
- 2025-10-31
AI Technical Summary
Existing technologies struggle to efficiently catalyze the reduction of carbon dioxide into multi-carbon products, particularly ethylene, under low-cost and low-temperature conditions. Furthermore, traditional methods require sophisticated equipment, making them unsuitable for large-scale production.
By using composite nanomaterials of silicon carbide and copper powder as catalysts, a nanocatalyst suitable for large-scale production was prepared through mechanical ball milling, ultrasonic centrifugation, and photocatalysis experiments. This catalyst can efficiently catalyze the reduction of CO2 to ethylene at low temperatures.
Nanoscale composite materials were successfully prepared at low temperatures with high product yields, especially ethylene, making them suitable for large-scale production and overcoming the equipment requirements and cost limitations of traditional methods.
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Figure CN120861111A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of new energy, and in particular relates to a method for preparing a nanocatalyst for the photocatalytic reduction of CO2 to ethylene. Background Technology
[0002] Silicon carbide (SiC) is a compound composed of silicon (Si) and carbon (C) elements. Its crystal structure is based on a tetrahedral structure, in which the bond distance between carbon atoms is approximately [missing information]. The bond distance between carbon and silicon atoms is Silicon carbide has a wide range of applications in various fields due to its high temperature resistance, high hardness, and excellent photoelectric properties, such as high-temperature materials, optical devices, electronic devices, aerospace, and grinding processes.
[0003] Currently, global carbon dioxide emissions are severe, causing a series of environmental problems such as the greenhouse effect and rising sea levels. Catalytic reduction of CO2 technology is of great research significance. Generally speaking, the products of catalytic CO2 reduction include C1 products such as CO and CH4, and under certain conditions, rare multi-carbon products can also appear. Compared with C1 products, multi-carbon products have more advantages in energy storage, energy conversion, and industrial value, so multi-carbon products are currently the main trend in catalytic CO2 reduction research.
[0004] Photocatalysis, a green chemical process driven by light energy, has the core advantage of directly converting light energy into chemical energy, demonstrating revolutionary potential in the energy field. Combining photocatalysis with catalytic CO2 reduction technology can open up new areas and breakthroughs in resource recycling. Summary of the Invention
[0005] The purpose of this invention is to provide a method for preparing a catalyst for the photocatalytic reduction of CO2 to ethylene. This method has a simple preparation process, readily available raw materials, and is suitable for large-scale production. This invention can reduce CO2 to the C2 product ethylene under photocatalytic conditions, and the ethylene yield is considerable.
[0006] The present invention discloses a method for preparing a nanocatalyst for the photocatalytic reduction of CO2 to ethylene, comprising the following steps:
[0007] Step 1: Raw material preparation.
[0008] Prepare 0.50g-0.90g of commercial silicon carbide powder and 0.10g-0.50g of copper powder.
[0009] Step 2: Mechanical ball milling.
[0010] Commercial silicon carbide powder and copper powder were mixed to ensure that each mixed powder weighed 1.00g. 0.90g of silicon carbide was mixed with 0.10g of copper powder, 0.80g of silicon carbide with 0.20g of copper powder, 0.70g of silicon carbide with 0.30g of copper powder, and 0.50g of silicon carbide with 0.50g of copper powder, respectively, to obtain mixed powders with copper doping concentrations of 10%, 20%, 30%, and 50%. Each 1.00g portion of mixed powder was then mechanically ball-milled for 20 hours at a speed of 250 rpm.
[0011] Step 3: Ultrasonic centrifugation.
[0012] Prepare a solution of the powder obtained in step 2 with deionized water. Place the solution in a clean beaker and sonicate for 1 hour. Then, take the upper and middle clear liquid from the beaker and perform gradient centrifugation. First, centrifuge at 3000 r / min for 5 minutes. After centrifugation, retain the clear liquid. Then, centrifuge the retained clear liquid at 8000 r / min for 5 minutes and retain the precipitate in the centrifuge tube. Finally, dry the precipitate.
[0013] Step 4: Photocatalysis experiment.
[0014] The photocatalytic experiment used a 300W xenon lamp to simulate the sunlight environment and a small water chiller to control the temperature environment at a constant 10℃ for 4 hours to test the photocatalytic reduction performance of carbon dioxide.
[0015] The present invention discloses a method for preparing a nanocatalyst for the photocatalytic reduction of CO2 to ethylene. The prepared nanocatalyst is used for the photocatalytic reduction of CO2 to carbon monoxide, methane, and ethylene.
[0016] The beneficial technical effects of this invention compared to the prior art are as follows:
[0017] The preparation method of the present invention can be carried out at low temperature, is simple to operate, has no special requirements for equipment, and is suitable for large-scale production.
[0018] This invention can catalytically reduce CO2 to yield C1 products such as CO and CH4, and C2 products such as C2H4, with yields of each product being quite considerable in the field of inorganic catalysts. In particular, it achieves a breakthrough by obtaining C2 products.
[0019] This invention breaks through the limitation of the ultra-hardness of silicon carbide and successfully obtains a silicon carbide-based nanoscale composite material. The material size observed under a scanning electron microscope is 100nm-200nm, and the particles are full, regular, and uniformly distributed.
[0020] This invention exhibits excellent performance under photocatalysis, and the obtained products are characterized by high yield and diversity, providing a new approach for the study of catalytic CO2 reduction and achieving a breakthrough in the production of ethylene products. Attached Figure Description
[0021] Figure 1 This is a scanning electron microscope (SEM) image of the copper-doped silicon carbide composite nanomaterial prepared in Example 1 of this invention.
[0022] Figure 2 This is an energy dispersive spectroscopy (EDS) image of the copper-doped silicon carbide composite nanomaterial prepared in Example 1 of this invention.
[0023] Figure 3 This is a graph showing the product yield of the silicon carbide copper-doped composite nanomaterial prepared in Example 1 of this invention under photocatalysis.
[0024] Figure 4 This is a scanning electron microscope (SEM) image of the copper-doped silicon carbide composite nanomaterial prepared in Example 2 of this invention.
[0025] Figure 5 This is an energy dispersive spectroscopy (EDS) image of the copper-doped silicon carbide composite nanomaterial prepared in Example 2 of this invention.
[0026] Figure 6 This is a graph showing the product yield of the silicon carbide copper-doped composite nanomaterial prepared in Example 2 of this invention under photocatalysis.
[0027] Figure 7 The yield diagram of the product of the silicon carbide copper-doped composite nanomaterial prepared in Example 3 of this invention under photocatalysis.
[0028] Figure 8 The yield diagram of the product of the silicon carbide copper-doped composite nanomaterial prepared in Example 4 of this invention under photocatalysis. Detailed Implementation
[0029] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0030] Example 1:
[0031] A method for preparing a photocatalyst for the reduction of CO2 to ethylene includes the following steps:
[0032] Step 1: Raw material preparation.
[0033] Prepare 0.90g of silicon carbide powder and 0.10g of copper powder.
[0034] Step 2: Mechanical ball milling.
[0035] Commercial silicon carbide powder and copper powder were mixed together, and the mass of the mixed powder was 1.00g. 0.90g of silicon carbide and 0.10g of copper powder were mixed separately to obtain a mixed powder with a copper doping concentration of 10%.
[0036] The mixed powder was subjected to mechanical ball milling for 20 hours at a speed of 250 r / min.
[0037] Step 3: Ultrasonic centrifugation.
[0038] Prepare a solution of the powder obtained in step 2 with deionized water. Place the solution in a clean beaker and sonicate for 1 hour. Then, take the upper and middle clear liquid from the beaker and perform gradient centrifugation. First, centrifuge at 3000 r / min for 5 minutes. After centrifugation, retain the clear liquid. Then, centrifuge the retained clear liquid at 8000 r / min for 5 minutes and retain the precipitate in the centrifuge tube. Finally, dry the precipitate.
[0039] Step 4: Photocatalysis experiment.
[0040] The photocatalytic experiment used a 300W xenon lamp to simulate the sunlight environment and a small water chiller to control the temperature environment at a constant 10℃ for 4 hours to test the photocatalytic reduction performance of carbon dioxide.
[0041] Figure 1 These are scanning electron microscope images of the silicon carbide composite nanomaterial doped with 10% copper powder prepared in Example 1 of this invention. Figure 1 As can be seen, at a magnification of ×20000, the average diameter of the particles is in the range of 100nm-200nm, and the particles are full and have a smooth, blocky structure.
[0042] Figure 2 This is an energy dispersive spectroscopy (EDS) image of the silicon carbide composite nanomaterial doped with 10% copper powder prepared in Example 1 of this invention. As can be seen from the image, in addition to the presence of Si and C elements, Cu elements are also present in the EDS.
[0043] Figure 3 This is a product yield diagram of the silicon carbide copper-doped composite nanomaterial prepared in Example 1 of the present invention under photocatalysis. It can be seen that after 4 hours of photocatalysis, the CO yield is 226.87 mol / g, the CH4 yield is 93.20 mol / g, and the C2H4 yield is 43.48 mol / g.
[0044] from Figure 1 , Figure 2 , Figure 3 As can be seen, the present invention successfully prepared a nanocomposite material, and obtained ethylene product with a considerable yield in the photocatalytic reduction of CO2, proving the correctness and success of the preparation method of the nanocatalyst for the catalytic reduction of carbon dioxide to ethylene.
[0045] Example 2:
[0046] A method for preparing a photocatalyst for the reduction of CO2 to ethylene includes the following steps:
[0047] Step 1: Raw material preparation.
[0048] Prepare 0.80g of silicon carbide powder and 0.20g of copper powder.
[0049] Step 2: Mechanical ball milling.
[0050] Commercial silicon carbide powder and copper powder were mixed together, and the mass of the mixed powder was 1.00g. 0.80g of silicon carbide and 0.20g of copper powder were mixed separately to obtain a mixed powder with a copper doping concentration of 20%.
[0051] The mixed powder was subjected to mechanical ball milling for 20 hours at a speed of 250 r / min.
[0052] Step 3: Ultrasonic centrifugation.
[0053] Prepare a solution of the powder obtained in step 2 with deionized water. Place the solution in a clean beaker and sonicate for 1 hour. Then, take the upper and middle clear liquid from the beaker and perform gradient centrifugation. First, centrifuge at 3000 r / min for 5 minutes. After centrifugation, retain the clear liquid. Then, centrifuge the retained clear liquid at 8000 r / min for 5 minutes and retain the precipitate in the centrifuge tube. Finally, dry the precipitate.
[0054] Step 4: Photocatalysis experiment.
[0055] The photocatalytic experiment used a 300W xenon lamp to simulate the sunlight environment and a small water chiller to control the temperature environment at a constant 10℃ for 4 hours to test the photocatalytic reduction performance of carbon dioxide.
[0056] Figure 4 These are scanning electron microscope images of the silicon carbide composite nanomaterial doped with 20% copper powder prepared in Example 2 of this invention. Figure 4 As can be seen, at a magnification of ×30000, the average diameter of the particles is in the range of 100nm-200nm, and the particles are full and have a smooth, blocky structure.
[0057] Figure 5 This is an energy dispersive spectroscopy (EDS) image of the silicon carbide composite nanomaterial doped with 20% copper powder prepared in Example 2 of this invention. As can be seen from the image, in addition to the presence of Si and C elements, Cu elements are also present in the EDS.
[0058] Figure 6This is a product yield diagram of the silicon carbide copper-doped composite nanomaterial prepared in Example 2 of the present invention under photocatalysis. It can be seen that after 4 hours of photocatalysis, the CO yield is 221.48 mol / g, the CH4 yield is 118.50 mol / g, and the C2H4 yield even reaches 173.41 mol / g.
[0059] Example 3:
[0060] A method for preparing a photocatalyst for the reduction of CO2 to ethylene includes the following steps:
[0061] Step 1: Raw material preparation.
[0062] Prepare 0.70g of silicon carbide powder and 0.30g of copper powder.
[0063] Step 2: Mechanical ball milling.
[0064] Commercial silicon carbide powder and copper powder were mixed together, and the mass of the mixed powder was 1.00g. 0.70g of silicon carbide and 0.30g of copper powder were mixed separately to obtain a mixed powder with a copper doping concentration of 30%.
[0065] The mixed powder was subjected to mechanical ball milling for 20 hours at a speed of 250 r / min.
[0066] Step 3: Ultrasonic centrifugation.
[0067] The powder obtained in step 2 was prepared into a solution with deionized water. The solution was placed in a clean beaker and sonicated for 1 hour. Then, the upper and middle clear liquid of the beaker was taken for gradient centrifugation. First, centrifugation was performed at 3000 r / min for 5 minutes. After the centrifugation, the clear liquid was retained. The retained clear liquid was then centrifuged at 8000 r / min for 5 minutes. The precipitate in the centrifuge tube was retained. Finally, the precipitate was dried to obtain the silicon carbide composite catalyst with a copper doping concentration of 30%.
[0068] Figure 7 This is a product yield diagram of the silicon carbide copper-doped composite nanomaterial prepared in Example 3 of the present invention under photocatalysis. It can be seen that after 4 hours of photocatalysis, the CO yield is 184.2 mol / g, the CH4 yield is 209.6 mol / g, and the C2H4 yield even reaches 182.8 mol / g.
[0069] Example 4:
[0070] A method for preparing a photocatalyst for the reduction of CO2 to ethylene includes the following steps:
[0071] Step 1: Raw material preparation.
[0072] Prepare 0.50g of silicon carbide powder and 0.50g of copper powder.
[0073] Step 2: Mechanical ball milling.
[0074] Commercial silicon carbide powder and copper powder were mixed together, with a mixed powder mass of 1.00g. 0.50g of silicon carbide and 0.50g of copper powder were then mixed separately to obtain a mixed powder with a copper doping concentration of 30%.
[0075] The mixed powder was subjected to mechanical ball milling for 20 hours at a speed of 250 r / min.
[0076] Step 3: Ultrasonic centrifugation.
[0077] The powder obtained in step 2 was prepared into a solution with deionized water. The solution was placed in a clean beaker and sonicated for 1 hour. Then, the upper and middle clear liquid of the beaker was taken for gradient centrifugation. First, centrifugation was performed at 3000 r / min for 5 minutes. After the centrifugation, the clear liquid was retained. The retained clear liquid was then centrifuged at 8000 r / min for 5 minutes. The precipitate in the centrifuge tube was retained. Finally, the precipitate was dried to obtain the silicon carbide composite catalyst with a copper doping concentration of 50%.
[0078] Figure 8 This is a product yield diagram of the silicon carbide copper-doped composite nanomaterial prepared in Example 4 of the present invention under photocatalysis. It can be seen that after 4 hours of photocatalysis, the CO yield is 200.40 mol / g, the CH4 yield is 106.5 mol / g, and the C2H4 yield even reaches 153.6 mol / g.
Claims
1. A method for preparing a photocatalyst for the reduction of CO2 to ethylene, characterized in that, Includes the following steps: Step 1: Raw material preparation; Prepare 0.50g-0.90g of commercial silicon carbide powder and 0.10g-0.50g of copper powder; Step 2: Mechanical ball milling; Commercial silicon carbide powder and copper powder were mixed to ensure that each mixed powder weighed 1.00g. 0.90g of silicon carbide was mixed with 0.10g of copper powder, 0.80g of silicon carbide with 0.20g of copper powder, 0.70g of silicon carbide with 0.30g of copper powder, and 0.50g of silicon carbide with 0.50g of copper powder, respectively, to obtain mixed powders with copper doping concentrations of 10%, 20%, 30%, and 50%. Each 1.00g portion of mixed powder was then mechanically ball-milled for 20 hours at a speed of 250 rpm. Step 3: Ultrasonic centrifugation; The powder obtained in step 2 was prepared into a solution with deionized water. The solution was placed in a clean beaker and sonicated for 1 hour. Then, the upper and middle clear liquid of the beaker was taken for gradient centrifugation. First, centrifugation was performed at 3000 r / min for 5 minutes. After the centrifugation, the clear liquid was retained. The retained clear liquid was then centrifuged at 8000 r / min for 5 minutes. The precipitate in the centrifuge tube was retained. Finally, the precipitate was dried. Step 4: Photocatalysis experiment; The photocatalytic experiment used a 300W xenon lamp to simulate the sunlight environment and a small water chiller to control the temperature environment at a constant 10℃ for 4 hours to test the photocatalytic reduction performance of carbon dioxide.
2. The method for preparing a photocatalyst for the reduction of CO2 to ethylene according to claim 1, characterized in that, The prepared nanocatalysts were used for photocatalytic reduction of CO2 to carbon monoxide, methane, and ethylene.