Plasma-assisted catalysis in-situ DRIFTS reactor

Abstract

The utility model discloses a plasma-assisted catalysis in-situ DRIFTS reactor, which comprises a shell, a plasma-assisted catalysis device, a plasma-assisted catalysis device, a plasma-assisted catalysis device and a DRIFTS reactor, the projection windows are arranged on the surface of the shell, and the number of the projection windows is at least three; the catalyst accommodating part is positioned in the accommodating cavity and is provided with a catalyst; one end of the high-voltage electrode extends into the catalyst and is matched with the ground electrode to form an electric field; the gas inlet is communicated with the catalyst accommodating part; by adopting innovative electrode configuration and layout, uniform electric field distribution and stable plasma discharge are realized, and meanwhile, the requirements of DRIFTS analysis are met.

Description

Technical Field

[0001] The utility model relates to the technical fields of catalytic reaction and spectral analysis, and particularly relates to a plasma-assisted catalytic in-situ DRIFTS reactor. Background Art

[0002] The plasma-assisted catalytic technology has broad application prospects in the fields of environmental governance, energy conversion, etc. However, the design of traditional plasma reactors often faces the following problems: the electric field distribution is uneven, resulting in low utilization rate of active sites on the catalyst surface; the discharge is unstable, prone to form hot spots or breakdown phenomena; the energy utilization efficiency is low, and most of the energy is converted into heat rather than effective chemical energy; the reactor structure is complex, and it is not easy to maintain and replace the catalyst. At the same time, for the study of the plasma-assisted catalytic reaction mechanism, in-situ DRIFTS analysis is an important characterization method, but the existing reactor designs often have difficulty in meeting the requirements of both plasma discharge and spectral analysis. At present, scholars at home and abroad have proposed various improvement schemes, such as using dielectric barrier discharge (DBD) technology, optimizing the electrode shape, etc. However, these schemes still have limitations. For example, the discharge space of the DBD reactor is limited, and it is difficult to process large-flux gases; while simply optimizing the electrode shape is difficult to take into account both uniform discharge and catalyst distribution. In addition, integrating the DRIFTS analysis window into the plasma reactor also faces many technical challenges. Therefore, it is of great significance to develop a reactor design that can simultaneously achieve uniform electric field distribution, stable discharge, efficient catalysis, and in-situ DRIFTS analysis. Summary of the Utility Model

[0003] To solve the above technical problems, the utility model provides a plasma-assisted catalytic in-situ DRIFTS reactor, which adopts an innovative electrode configuration and layout to achieve uniform electric field distribution and stable plasma discharge, and at the same time meets the requirements of DRIFTS analysis.

[0004] The utility model adopts the following technical solutions:

[0005] A plasma-assisted catalytic in-situ DRIFTS reactor, comprising: a housing, having a receiving cavity and a ground electrode; a projection window, disposed on the surface of the housing, with at least 3; a catalyst receiving part, located in the receiving cavity, having a catalyst; a high-voltage electrode, one end extending into the catalyst, cooperating with the ground electrode to form an electric field; a gas inlet, communicating with the catalyst receiving part; and a gas outlet, communicating with the catalyst receiving part.

[0006] Preferably, the housing includes a base and a dome, and at least part of the dome is made of a conductive material.

[0007] Preferably, there are 3 projection windows. Infrared light enters from one of the projection windows, reflects in the catalyst accommodating part, and exits from any one of the remaining projection windows.

[0008] Preferably, the bottom of the housing has a mounting groove, and the high-voltage electrode is located in the mounting groove and one end extends into the catalyst.

[0009] Preferably, the accommodating cavity is made of a material resistant to high temperature and corrosion. The inner diameter of the accommodating cavity is 30 - 100 mm, and the height is 50 - 200 mm.

[0010] Preferably, the material of the high-voltage electrode is platinum or tungsten. The diameter of the high-voltage electrode is 0.5 - 2 mm, and the length is 30 - 150 mm.

[0011] Preferably, the high-voltage electrode is 3 - 5 mm away from the catalyst surface.

[0012] Preferably, there is a catalyst support mechanism in the catalyst accommodating part. The catalyst is located on the catalyst support mechanism, and the thickness of the catalyst is 5 - 30 mm.

[0013] Preferably, the gas inlet is arranged at the bottom of the base, and the gas outlet is arranged on the upper surface of the base.

[0014] Preferably, the projection window is made of an infrared transparent material.

[0015] Compared with the prior art, the present utility model has the following advantages:

[0016] 1. The present utility model provides a plasma-assisted catalytic in-situ DRIFTS reactor based on optimized electric field design. Through innovative electrode configurations and layouts, uniform electric field distribution and stable plasma discharge are achieved, while meeting the requirements of in-situ spectral analysis. The reactor consists of multiple key components such as a housing, projection windows, a catalyst accommodating part, and high-voltage electrodes. Each component is carefully designed and closely cooperates with each other to jointly form an efficient plasma catalysis and in-situ analysis system.

[0017] 2. Uniform electric field distribution: By optimizing the electrode configurations and layouts, uniform electric field distribution within the catalyst layer is achieved.

[0018] 3. Stable discharge: The needle-dome electrode structure is adopted to effectively suppress local discharge and the formation of hot spots.

[0019] 4. High energy utilization rate: The plasma directly acts on the catalyst surface, improving the energy conversion efficiency.

[0020] 5. Simple structure: The modular design facilitates maintenance and catalyst replacement.

[0021] 6. Wide applicability: The electrode spacing and the thickness of the catalyst layer can be adjusted according to different reaction requirements.

[0022] 7. In-situ analysis: An integrated DRIFTS window enables real-time spectral monitoring during the reaction process. Description of the Drawings

[0023] Figure 1 It is a schematic structural diagram of the reactor of the present utility model.

[0024] Figure 2 It is a sectional view of the reactor of the present utility model.

[0025] In the figure, housing 1, accommodation chamber 1-1, base 1-2, dome 1-3, installation groove 1-4, projection window 2, catalyst accommodation part 3, catalyst support mechanism 3-1, catalyst layer 3-2, high-voltage electrode 4, gas inlet 5, gas outlet 6. Detailed Embodiments

[0026] For the convenience of understanding the technical solution of the present utility model, the following will be described in detail in conjunction with the drawings and specific embodiments.

[0027] As Figure 1-2 shown, a plasma-assisted catalytic in-situ DRIFTS reactor includes a housing 1, a projection window 2, a catalyst accommodation part 3, and a high-voltage electrode 4;

[0028] The housing 1 includes a base 1-2 and a dome 1-3. The base 1-2 has an accommodation chamber 1-1. The accommodation chamber 1-1 and the dome 1-3 cooperate to form a reaction space. The dome 1-3 includes a ground electrode layer, which is integrally designed with the dome body, and the material is stainless steel or gold-plated copper, with a thickness of 3-10 mm. The bottom of the housing 1 has an installation groove 1-4 for accommodating the high-voltage electrode 4;

[0029] Three projection windows 2 are provided on the surface of the housing 1. Infrared light enters from one of the projection windows 2, is reflected by the catalyst accommodation part 3, and exits from any one of the remaining projection windows 2. Specifically, the corresponding projection window 2 can be selected according to the scenario during use and the positions of other devices; The projection window 2 is made of an infrared transparent material (such as ZnSe or KBr), and the angle is optimized to obtain the best signal. The angle between the projection window 2 and the horizontal plane can be selected to be 55-60 degrees;

[0030] The catalyst accommodation part 3 is located in the accommodation chamber 1-1 and has a catalyst layer 3-2, which is the main area where the reaction occurs; The thickness of the catalyst layer is 5-30 mm, and different catalysts can be selected according to the reaction requirements; The catalyst layer is formed by stacking granular catalysts and does not hinder the flow of reaction gases;

[0031] The high-voltage electrode 4 is disposed in the mounting groove 1-4, and one end extends into the catalyst to form an electric field in cooperation with the ground electrode. After the high-voltage electrode 4 is energized, a stable plasma discharge is formed between the high-voltage electrode 4 and the ground electrode. As a preferred embodiment, the high-voltage electrode 4 has a needle-like structure, is made of platinum or tungsten, has a diameter of 0.5-2 mm, and a length of 30-150 mm. The high-voltage electrode 4 with an appropriate diameter and length can be selected according to specific conditions during use.

[0032] The gas inlet 5 is located at the lower end of the base 1-2 and communicates with the catalyst accommodating portion 3. It is the inlet for the reaction gas and has an inner diameter of 2-5 mm.

[0033] The gas outlet 6 is located at the upper end of the base 1-2 and communicates with the catalyst accommodating portion 3. It is the outlet for the reaction gas and has an inner diameter of 2-5 mm.

[0034] The reaction gas enters from the gas inlet 5 at the lower end of the base 1-2, passes through the catalyst, and then exits from the gas outlet 6. That is, the gas outlet 6 and the gas inlet 5 are located at the upper and lower ends of the catalyst to ensure that the reaction gas can pass through the catalyst.

[0035] As a preferred embodiment, the accommodating cavity 1-1 is made of a material with high temperature resistance and corrosion resistance, such as quartz glass or ceramic, with an inner diameter of 30-100 mm and a height of 50-200 mm.

[0036] The present utility model not only solves the problems of uneven electric field distribution and unstable discharge in traditional plasma reactors, but also realizes the combination of an efficient plasma-assisted catalytic process and in-situ DRIFTS analysis. This provides an ideal experimental platform for in-depth study of the plasma-assisted catalytic reaction mechanism and is of great significance for basic research and application development in the fields of environmental governance and energy conversion.

[0037] Example 1

[0038] The accommodation chamber 1-1 is made of quartz glass, with an inner diameter of 50 mm and a height of 100 mm. The high-voltage electrode 4 is a platinum needle, with a diameter of 1 mm and a length of 80 mm. The ground electrode is integrated with the dome 1-3, with a thickness of 5 mm. The thickness of the catalyst layer is 15 mm, and a 5 wt% Ni / Al2O3 catalyst is used. The inner diameters of both the gas inlet 5 and the gas outlet 6 are 3 mm. The DRIFTS analysis window (projection window 2) is made of ZnSe material, with a diameter of 20 mm, set on the side wall of the reactor at an angle of 60°. During operation, the high-voltage electrode 4 is adjusted so that the top of it is 3 mm away from the catalyst surface. A mixed gas of N2 and H2 (N2:H2 = 1:3) is introduced, with a total flow rate of 100 mL / min. An AC voltage of 15 kV is applied, with a frequency of 10 kHz. The reaction temperature is controlled at 400 °C. Under these conditions, the reactor can operate stably for more than 8 hours, and the production rate of NH3 is twice that of traditional heating catalysis. At the same time, DRIFTS analysis clearly shows the formation and evolution process of N-H and Ni-N species on the catalyst surface.

[0039] Example 2

[0040] The accommodation chamber 1-1 is made of alumina ceramic, with an inner diameter of 80 mm and a height of 150 mm. The high-voltage electrode is a tungsten needle, with a diameter of 1.5 mm and a length of 120 mm. The ground electrode is a gold-plated copper cover, with a thickness of 8 mm. The thickness of the catalyst layer is 25 mm, and a 10 wt% Fe-K / Al2O3 catalyst is used. The inner diameters of both the gas inlet 5 and the gas outlet 6 are 4 mm. The DRIFTS analysis window is made of KBr material, with a diameter of 25 mm, set at an angle of 55°. During operation, the high-voltage electrode 4 is adjusted so that the top of it is 4 mm away from the catalyst surface. A mixed gas of CO2 and H2 (CO2:H2 = 1:4) is introduced, with a total flow rate of 200 mL / min. An AC voltage of 20 kV is applied, with a frequency of 15 kHz. The reaction temperature is controlled at 350 °C. Under these conditions, the conversion rate of CO2 reaches 65%, and the selectivity of CH4 is 80%, with performance superior to that of traditional fixed-bed reactors. DRIFTS analysis shows that the plasma significantly promotes the formation of surface HCOO- and CO3 2 - intermediates, and the concentration of these intermediates is about three times higher than that under traditional thermal catalytic conditions.

[0041] The above are only the preferred embodiments of the present invention. The protection scope of the present invention is subject to the scope defined by the claims. Several improvements and refinements made by those skilled in the art without departing from the spirit and scope of the present invention should also be regarded as within the protection scope of the present invention.

Claims

1. A plasma-assisted catalytic in-situ DRIFTS reactor, characterized in that: include: A housing (1) having a containing cavity (1-1) and a ground electrode; Projection windows (2) are arranged on the surface of the housing (1), and there are at least three of them; A catalyst containing part (3), located in the containing chamber (1-1), containing a catalyst; A high voltage electrode (4) has one end extending into the catalyst and cooperates with the ground electrode to form an electric field; A gas inlet (5) connected to the catalyst containing portion (3); The gas outlet (6) is connected to the catalyst containing part (3).

2. The plasma-assisted catalytic in-situ DRIFTS reactor according to claim 1, characterized in that: The housing (1) comprises a base (1-2) and a dome (1-3); the dome (1-3) is at least partially made of conductive material.

3. The plasma-assisted catalytic in-situ DRIFTS reactor according to claim 1, characterized in that: There are three projection windows (2), and the infrared light enters from one of the projection windows (2), is reflected by the catalyst containing part (3), and then exits from any of the remaining projection windows (2).

4. The plasma-assisted catalytic in-situ DRIFTS reactor according to claim 1, characterized in that: The bottom of the shell (1) is provided with a mounting groove (1-4), and the high-voltage electrode (4) is located in the mounting groove (1-4) and one end of the electrode extends into the catalyst.

5. The plasma-assisted catalytic in-situ DRIFTS reactor according to claim 1, characterized in that: The accommodating cavity (1-1) is made of high temperature resistant and corrosion resistant materials, and the inner diameter of the accommodating cavity (1-1) is 30-100 mm and the height is 50-200 mm.

6. The plasma-assisted catalytic in-situ DRIFTS reactor according to claim 1, characterized in that: The material of the high-voltage electrode (4) is platinum or tungsten, the diameter of the high-voltage electrode (4) is 0.5-2 mm, and the length is 30-150 mm.

7. The plasma-assisted catalytic in-situ DRIFTS reactor according to claim 6, characterized in that: The high voltage electrode (4) is 3-5 mm away from the catalyst surface.

8. The plasma-assisted catalytic in-situ DRIFTS reactor according to claim 1, characterized in that: The catalyst containing part (3) has a catalyst supporting mechanism (3-1) in it, the catalyst is located on the catalyst supporting mechanism (3-1), and the thickness of the catalyst is 5-30 mm.

9. The plasma-assisted catalytic in-situ DRIFTS reactor according to claim 2, characterized in that: The gas inlet (5) is arranged at the bottom of the base (1-2), and the gas outlet (6) is arranged on the upper surface of the base (1-2).

10. The plasma-assisted catalytic in-situ DRIFTS reactor according to claim 1, characterized in that: The projection window (2) is made of infrared transparent material.

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