Metal carrier for improving catalytic activity and manufacturing process thereof

Abstract

The invention relates to the technical field of metal carriers, in particular to a metal carrier for improving catalytic activity and a manufacturing process thereof. A metal carrier capable of improving catalytic activity comprises a cylindrical shell and a metal carrier inner core fixedly arranged in the shell, the metal carrier inner core is cylindrical and comprises a plurality of corrugated plates, the corrugated plates are provided with periodic sinusoidal waveform structures in the radial direction of the metal carrier inner core, and the periodic sinusoidal waveform structures are arranged on the outer surface of the metal carrier inner core. The corrugated plates extend in the axial direction of the metal carrier inner core, and every two adjacent corrugated plates are stacked in a staggered mode in the radial direction of the metal carrier inner core and connected in a brazed mode. According to the metal carrier capable of improving the catalytic activity, waste gas can move in the axial direction and the radial direction of the carrier at the same time, the catalytic activity is good, the catalytic efficiency is high, and the technical problems that waste gas cannot move in the radial direction in an existing metal carrier with a straight-through type pore channel, the catalytic activity is poor, and the catalytic efficiency is low are solved.

Description

Technical Field

[0001] This invention relates to the field of metal support technology, and in particular to a metal support for improving catalytic activity and its manufacturing process. Background Technology

[0002] Metal supports have shown broad application potential in various fields, particularly in the environmental protection sector, specifically in the purification of automotive and motorcycle exhaust gases. In automotive exhaust purification, metal-supported catalysts are gradually replacing traditional ceramic-supported catalysts due to their advantages such as high thermal conductivity, high mechanical strength, low back pressure, rapid ignition, large porosity, and light weight. Currently, the most widely used metal honeycomb supports on the market are mainly of the following types: 1. Ordinary straight-through metal honeycomb carrier. This type of carrier has low back pressure, but the waste gas stays in the carrier for a short time, resulting in a low catalytic conversion rate. Usually, a large amount of precious metal loading is required to achieve a high catalytic conversion rate. 2. Zirconia-rich support, commonly known as LS-type support, is a composite oxide material composed of rare earth oxides, silicon dioxide (SiO2), and zirconium dioxide (ZrO2). The LS-type support structure adds more longitudinal pores to a straight-through metal honeycomb support, resulting in a dense pore structure and highly dispersed surface area. This provides a uniform dispersion platform for the active metal catalyst. This structure significantly improves catalytic reaction efficiency but also increases back pressure, leading to a certain loss of engine power.

[0003] 3. Perforated carrier, also known as PE carrier. This type of carrier is formed by punching specific holes into a thin plate, creating a turbulent flow effect and enhancing the contact efficiency between the exhaust gas and the catalyst. Compared with traditional smooth carriers, the PE structure significantly improves the conversion rate, while the increase in back pressure is not too significant.

[0004] The above-mentioned carriers all have straight-through channel structures, resulting in very short residence times of exhaust gas on the carrier, leading to poor catalytic activity and low catalytic efficiency. Furthermore, these carriers are manufactured using foil and flat strips, typically rolled into an S-shape. While this rolling method addresses the issues of structural strength and metal creep fatigue in metal carriers, it also restricts radial gas flow within the carrier. Rolling into an SM-shaped carrier would be technically more complex and costly. Summary of the Invention

[0005] In response to the problems raised in the background art, the purpose of this invention is to provide a metal carrier that improves catalytic activity, enabling waste gas to move simultaneously along the axial and radial directions of the carrier, resulting in good catalytic activity and high catalytic efficiency. This solves the technical problem that waste gas cannot move radially in existing straight-channel metal carriers, resulting in poor catalytic activity and low catalytic efficiency.

[0006] Another objective of this invention is to propose a method for manufacturing a metal support for improving catalytic activity, which employs a spinning and brazing method to tightly hold the core of the metal support, thereby solving the problem of the core easily detaching.

[0007] The above-mentioned technical objective of the present invention is achieved through the following technical solution: A metal support for improving catalytic activity includes a cylindrical outer shell and a metal support core fixedly disposed inside the outer shell. The metal support core is cylindrical and includes multiple corrugated plates. The corrugated plates have a periodic sinusoidal waveform structure along the radial direction of the metal support core and extend along the axial direction of the metal support core. Adjacent corrugated plates are staggered and stacked along the radial direction of the metal support core and brazed together. Multiple non-linear gas flow channels extending along the axial direction of the metal support core are formed between adjacent corrugated plates. The corrugated plate has a through hole along its surface, and two adjacent gas flow channels are connected by the through hole so that when the gas enters the inner core of the metal carrier, it moves synchronously along the extension direction of the gas flow channel and along the radial direction of the inner core of the metal carrier.

[0008] Optionally, the connecting hole is opened at the contact point where two adjacent corrugated plates are stacked in a staggered manner.

[0009] Optionally, the corrugated plate extends along the axial direction of the inner core of the metal carrier to form an S-shaped meandering structure, and the meandering paths of two adjacent corrugated plates cooperate with each other, and the gas flow channel extends in an S-shape along the axial direction of the inner core of the metal carrier.

[0010] Optionally, the corrugated plate has multiple bends along the axial direction of the inner core of the metal carrier, and the connecting hole is opened at the bend.

[0011] Optionally, the corrugated plate extends in a periodic bending motion along the axial direction of the inner core of the metal carrier, and the connecting holes are periodically and uniformly arranged along the meandering path of the corrugated plate.

[0012] Optionally, when two adjacent corrugated plates are stacked, the waveform of the upper corrugated plate has a phase difference of 45° relative to the waveform of the lower corrugated plate.

[0013] Optionally, the peak height L1 of the corrugated plate is 1.3 mm and the peak width L2 is 2.8 mm.

[0014] Optionally, the thickness of the corrugated plate is 0.1 to 0.15 mm.

[0015] Optionally, the shape of the connecting hole can be racetrack-shaped, circular, elliptical, or polygonal.

[0016] A method for preparing a metal support for enhancing catalytic activity, the method comprising the following steps: Step S1: Fabrication of the metal carrier core: The corrugated plate is installed into the mold for splicing, welding powder is sprayed, and then high-temperature brazing is performed. After cleaning and drying, the metal carrier core is obtained. Step S2, encapsulation of the metal carrier core: the metal carrier core is wrapped with a non-expansion gasket and pressed into the outer shell. The middle part of the outer shell is spun and the ends of the outer shell are enlarged to obtain the metal carrier. Step S3, High-temperature oxidation: The metal support is calcined; Step S4, Catalyst Coating: Coating the catalyst slurry onto the inner core of the metal carrier of the metal carrier; Step S5: After drying the coated metal support, calcine it and cool it to obtain a metal support with improved catalytic activity.

[0017] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: 1. The corrugated plates have a periodic sinusoidal waveform structure along the radial direction of the inner core of the metal carrier, and the corrugated plates extend along the axial direction of the inner core of the metal carrier. Adjacent corrugated plates are staggered and stacked along the radial direction of the inner core of the metal carrier and brazed together, thereby forming multiple gas flow channels extending along the axial direction of the inner core of the metal carrier between the two adjacent corrugated plates. The gas flow channels are non-linear, which can increase the collision between the exhaust gas and the pore walls of the gas flow channels of the metal carrier, thereby forming stronger turbulence. This improves the catalytic activity of the metal carrier. The special channel structure (non-linear) also allows the metal carrier to have a larger geometric surface area, that is, higher conversion efficiency.

[0018] 2. By creating connecting holes along the surface of the corrugated plate, the back pressure increased by turbulence in the gas flow channels is released. Simultaneously, this allows the exhaust gas to move not only axially within the metal carrier core but also radially. The exhaust gas can diffuse from one gas flow channel into an adjacent channel through the connecting holes. This radial movement provides the exhaust gas with more opportunities to contact the active components of the catalyst, increasing the reaction area between the exhaust gas and the catalyst, as well as the residence time of the exhaust gas in the catalyst, thus significantly improving catalytic activity.

[0019] 3. By pre-sealing and spinning, the coating process is moved forward, which not only allows the outer shell to hold the metal carrier core tightly in advance to prevent the carrier from detaching from the core, but also saves sealing time. In addition, because the thermal expansion coefficients of the metal outer shell and the metal carrier core are different, the metal carrier core is prone to cracking, which can lead to core detachment and blockage of the exhaust pipe. In the manufacturing process, spinning and brazing are used to hold the metal carrier core tightly, thus solving the problem of the core easily detaching. Attached Figure Description

[0020] Figure 1 This is a front view of a metal support for improving catalytic activity according to an embodiment of the present invention.

[0021] Figure 2 yes Figure 1 Enlarged view of point A.

[0022] Figure 3 This is a waveform diagram of the corrugated plate of the metal support core of the metal support for improving catalytic activity according to an embodiment of the present invention.

[0023] Figure 4 This is a cross-sectional view of a metal support for improving catalytic activity according to an embodiment of the present invention.

[0024] Figure 5 yes Figure 4 Enlarged view of point B.

[0025] In the attached diagram: 1-outer shell, 2-metal carrier inner core, 21-corrugated plate, 211-connecting hole, 212-inflection point, 22-gas flow channel, 23-contact point. Detailed Implementation

[0026] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0027] like Figures 1 to 5 As shown, a metal support for improving catalytic activity includes a cylindrical outer shell 1 and a metal support core 2 fixedly disposed inside the outer shell 1. The metal support core 2 is cylindrical and includes multiple corrugated plates 21. The corrugated plates 21 have a periodic sinusoidal waveform structure along the radial direction of the metal support core 2, and the corrugated plates 21 extend along the axial direction of the metal support core 2. Adjacent corrugated plates 21 are stacked and brazed together in a staggered manner along the radial direction of the metal support core 2. Multiple non-linear gas flow channels 22 extending along the axial direction of the metal support core 2 are formed between adjacent corrugated plates 21. The corrugated plate 21 has a through hole 211 extending through its surface. Two adjacent gas flow channels 22 are connected through the through hole 211 so that when the gas enters the inner core 2 of the metal carrier, it moves synchronously along the extension direction of the gas flow channel 22 and along the radial direction of the inner core 2 of the metal carrier.

[0028] Currently, the pore structure of conventional metal carriers is usually parallel to the axial direction of the metal carrier, i.e., a straight-through type, while the radial direction of the metal carrier is not open. Exhaust gas can only move along the pores in a direction parallel to the axial direction of the metal carrier. In the metal carrier of this invention, the corrugated plate 21 has a periodic sinusoidal waveform structure along the radial direction of the inner core 2 of the metal carrier, and the corrugated plate 21 extends along the axial direction of the inner core 2 of the metal carrier. Adjacent corrugated plates 21 are staggered and stacked along the radial direction of the inner core 2 of the metal carrier and brazed together, thereby forming multiple gas flow channels 22 extending along the axial direction of the inner core 2 of the metal carrier between adjacent corrugated plates 21. The gas flow channels 22 are non-linear, which increases the collision between the exhaust gas and the pore walls of the gas flow channels 22 of the metal carrier, forming stronger turbulence, thereby improving the catalytic activity of the metal carrier. The special channel structure (non-linear) also allows the metal carrier to have a larger geometric surface area, i.e., higher conversion efficiency.

[0029] However, increased turbulence inevitably leads to increased back pressure, which can affect engine performance. Therefore, a connecting hole 211 is provided along the surface of the corrugated plate 21 to release the increased back pressure caused by turbulence in the gas flow channels 22. Simultaneously, this allows exhaust gas to move not only axially but also radially within the metal carrier core 2. Exhaust gas can diffuse from one gas flow channel 22 through the connecting hole 211 into an adjacent gas flow channel 22. This radial movement provides more opportunities for the exhaust gas to contact the active components of the catalyst, increasing the reaction area between the exhaust gas and the catalyst, as well as the residence time of the exhaust gas in the catalyst, thus significantly improving catalytic activity.

[0030] Furthermore, since the multiple gas flow channels 22 are interconnected, the exhaust gas can continuously move into the multiple gas flow channels 22 when it moves radially, achieving the effect of "one hole, multiple outlets" (that is, after the exhaust gas enters one gas flow channel 22 along the axial direction of the inner core 2 of the metal carrier, it can move radially into multiple gas flow channels 22 through the connecting port).

[0031] It should be noted that existing metal carrier cores are typically made by combining foil strips and flat strips and then rolling them together. Because they are made by rolling foil strips and flat strips, the gas flow channels 22 cannot be connected radially. However, the metal carrier core 2 of this catalytically enhanced metal carrier is made by staggered stacking and brazing of the corrugated plates 21. It does not require flat strips or rolling processes. By setting the connecting holes 211, multiple gas flow channels 22 are connected, thereby enabling the radial movement of exhaust gas in the metal carrier core 2.

[0032] The aforementioned metal support for enhancing catalytic activity allows waste gas to move simultaneously along the axial and radial directions of the support, resulting in good catalytic activity, high catalytic efficiency, and a high conversion rate of hydrocarbons (HC). This solves the technical problem that waste gas cannot move radially in existing straight-channel metal supports, leading to poor catalytic activity and low catalytic efficiency.

[0033] In one embodiment of the present invention, the density of the corrugated plate 21 is 7.16 g / cm³. 3 The corrugated plate 21, with a thickness of 0.1 mm, a diameter of 118 mm, and a height of 90 mm, weighs 805 g. Therefore, the volume of the corrugated plate 21 is 805 / 7.16 = 112.4 cm³. 3 The volume of the metal carrier is The surface area of ​​the corrugated plate 21 is The geometric surface area of ​​the metal carrier is 22480 / 10000 / (983.73 / 1000) = 2.285m². 2 / L.

[0034] Preferably, the connecting hole 211 is opened at the contact point 23 where two adjacent corrugated plates 21 are stacked in a staggered manner.

[0035] Because the two adjacent corrugated plates 21 are stacked in a radially staggered manner along the inner core 2 of the metal carrier, that is, the two adjacent corrugated plates 21 naturally form discrete and regularly distributed contact points at the contact point 23. By opening the connecting hole 211 at the contact point 23, the exhaust gas can move radially from one gas flow channel 22 and enter another gas flow channel 22 adjacent to the contact point 23, which effectively controls the increase of back pressure while enhancing turbulence and catalytic activity.

[0036] like Figure 4 As shown, preferably, the corrugated plate 21 bends and extends along the axial direction of the inner core 2 of the metal carrier to form an S-shaped meandering structure, and the meandering paths of two adjacent corrugated plates 21 cooperate with each other, and the gas flow channel 22 extends in an S-shape along the axial direction of the inner core 2 of the metal carrier.

[0037] The corrugated plate 21 extends along the axial direction of the inner core 2 of the metal carrier, forming an S-shaped meandering structure. The meandering paths of two adjacent corrugated plates 21 cooperate with each other to form a non-linear gas flow channel 22 (at this time, the gas flow channel 22 extends along the axial direction of the inner core 2 of the metal carrier in an S-shape), which can increase the collision between the exhaust gas and the pore wall of the gas flow channel 22 to form stronger turbulence, thereby improving the catalytic activity.

[0038] Preferably, the corrugated plate 21 has multiple bends 212 along the axial bend of the inner core 2 of the metal carrier, and the connecting hole 211 is opened at the bends 212.

[0039] The corrugated plate 21 is arranged along the axial direction of the inner core 2 of the metal carrier. Multiple inflection points 212 are provided at the bends of the axial meandering. Since local high pressure is easily generated at the inflection point 212 due to the sudden change in flow direction, by providing the connecting hole 211 at the inflection point 212, a strong driving force can be provided for the radial movement of the exhaust gas, which is conducive to driving the exhaust gas through the connecting hole 211 into another gas flow channel 22.

[0040] Preferably, the corrugated plate 21 extends in a periodic bending motion along the axial direction of the inner core 2 of the metal carrier, and the connecting holes 211 are periodically and uniformly arranged along the meandering path of the corrugated plate 21. This ensures that each segment of the gas flow channel 22 in the axial direction is effectively and evenly utilized, guaranteeing that the catalyst in the inner core 2 of the metal carrier is used uniformly. Furthermore, the periodic pressure release points prevent drastic fluctuations in back pressure, thus stabilizing the back pressure.

[0041] Preferably, when two adjacent corrugated plates 21 are stacked, the waveform of the upper corrugated plate 21 has a phase difference of 45° relative to the waveform of the lower corrugated plate 21.

[0042] Specifically, the corrugated plate 21 has a sinusoidal waveform, defined by the equation Y(x) = 0.65sin(2.24x) + 0.65, where x is the coordinate along the periodic extension direction of the corrugations of the corrugated plate 21 (i.e., the radial direction of the inner core 2 of the metal carrier), and Y(x) refers to the vertical height of the corrugated plate 21 at position x. This sinusoidal equation is the characteristic curve of the corrugated plate 21 with this sinusoidal waveform. x determines the peak width, which is an indicator of the density of the gas flow channel 22, and Y(x) determines the peak height L1. Both determine the cross-sectional area of ​​the formed gas flow channel 22 along the radial direction of the inner core 2 of the metal carrier.

[0043] Specifically, along the direction of corrugation extension, adjacent corrugated plates 21 are shifted a certain distance, such that the phase difference between the waveforms of the two corrugated plates 21 is 45°. This staggered stacking method allows the corrugated surfaces of the two corrugated plates 21 to contact and weld together, forming an approximately S-shaped, meandering gas flow channel 22. Exhaust gas flows in the gas flow channel 22 and, through the connecting hole 211, allows the gas to radially pass from one gas flow channel 22 to another adjacent gas flow channel 22, greatly increasing mixing and contact efficiency.

[0044] Furthermore, a constant 45° phase difference can form multiple S-shaped gas flow channels 22 with regular and uniform radial cross-sections within the inner core 2 of the metal carrier. This achieves a uniform "one-channel-multiple-outlets" effect throughout the entire inner core 2 of the metal carrier, avoiding flow dead zones.

[0045] like Figure 3 As shown, in one embodiment of the present invention, the peak height L1 of the corrugated plate 21 is 1.3 mm and the peak width L2 is 2.8 mm.

[0046] Based on the peak height L1 and peak width L2 of the corrugated plate 21, adjacent corrugated plates 21 are stacked in a staggered manner, and the phase difference between the waveform of the upper corrugated plate 21 and the waveform of the lower corrugated plate 21 is 45°. This ensures that the cross-sections of the multiple gas flow channels 22 formed in the radial direction of the inner core 2 of the metal carrier are regular and their sizes are basically consistent. If the cross-sections of the multiple gas flow channels 22 in the radial direction of the inner core 2 of the metal carrier are irregular, it is easy to cause uneven air intake and will also have a certain negative impact on back pressure. In addition, if the gas flow channels 22 are too small, they are easy to be blocked when coating the slurry in the subsequent metal carrier manufacturing process, which will cause the back pressure to rise and, in severe cases, damage the engine.

[0047] Preferably, the thickness of the corrugated plate 21 is 0.1 to 0.15 mm.

[0048] By increasing the thickness of the corrugated plate 21 to 0.1–0.15 mm, the heat resistance and structural strength of the metal carrier core 2 can be improved. Since it is difficult to roll excessively thick foil, existing foils produced by rolling methods cannot achieve this thickness; typically, the thickness of rolled foil is 0.05–0.08 mm. However, this structure of the metal carrier for improving catalytic activity does not employ a rolling method, allowing the use of a thicker corrugated plate 21, thereby improving the overall compressive strength and thermal shock resistance of the metal carrier.

[0049] Specifically, the corrugated plate 21 is made of iron-chromium-aluminum material.

[0050] Optionally, the shape of the connecting hole 211 can be racetrack-shaped, circular, elliptical, or polygonal.

[0051] Preferably, the connecting hole 211 is racetrack shaped and is arranged along the meandering direction of the corrugated plate 21. In the same corrugated plate 21, the distance between the center points of two adjacent connecting holes 211 is 5.6 mm, the length of the connecting hole 211 is 6 mm, and the width of the connecting hole 211 is 1 mm.

[0052] A method for preparing a metal support for enhancing catalytic activity, the method comprising the following steps: Step S1, Fabrication of the metal carrier inner core 2: The corrugated plate 21 is installed into the mold for splicing, welding powder is sprayed, and then high-temperature brazing is performed. After cleaning and drying, the metal carrier inner core 2 is obtained. Step S2, encapsulation of metal carrier core 2: wrap the metal carrier core 2 with a non-expansion gasket, press it into the outer shell 1, spin the middle part of the outer shell 1, and enlarge the end of the outer shell 1 to obtain the metal carrier. Step S3, High-temperature oxidation: The metal support is calcined; Step S4, Catalyst Coating: The catalyst slurry is coated onto the inner core 2 of the metal carrier of the metal carrier; Step S5: After drying the coated metal support, calcine it and cool it to obtain a metal support with improved catalytic activity.

[0053] Conventional catalysts are typically coated before encapsulation. This invention's method for manufacturing the metal carrier involves pre-encapsulation and spinning, bringing the coating process forward. This not only ensures the outer shell 1 holds the metal carrier core tightly to prevent detachment but also saves encapsulation time, thus shortening the finished product delivery time and reducing the cost of encapsulation molds. Furthermore, because the thermal expansion coefficients of the metal outer shell 1 and the metal carrier core 2 differ, the metal carrier core 2 is prone to cracking, leading to detachment and blockage of the exhaust pipe. The manufacturing process employs spinning and brazing to tightly hold the metal carrier core 2, thus solving the problem of core detachment.

[0054] The following describes the effects of the metal carrier structure of the present invention with reference to specific embodiments. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products.

[0055] Example 1 A metal support for enhancing catalytic activity is prepared by the following steps: Step S1: Fabrication of the metal carrier core: The corrugated plate is installed into the mold for splicing, welding powder is sprayed, and then high-temperature brazing is performed. After cleaning and drying, the metal carrier core is obtained. The corrugated plate has a peak height L1 of 1.3 mm and a peak width L2 of 2.8 mm, and its shape is a sinusoidal waveform. This sinusoidal waveform is defined by the equation Y(x) = 0.65sin(2.24x) + 0.65. When two adjacent layers of the corrugated plate are stacked, the waveform of the upper layer has a phase difference of 45° relative to the waveform of the lower layer. The density of the corrugated plate is 7.16 g / cm³. 3 The thickness is 0.1mm, and the diameter of the metal carrier inner core is 118mm and the height is 90mm. Step S2, Encapsulation of the metal carrier core: Wrap the metal carrier core with a non-expansion gasket and press it into the outer shell (the height of the outer shell is 120mm). Spin-form the middle part of the outer shell in the height direction (the length of the spin-formed section is 45mm, and the depth of the single-sided spin-formed section is 4.5mm). After spin-forming, place the metal carrier core on an electronic universal testing machine and test the bonding strength between the outer shell and the core with a 20mm diameter indenter. Then, enlarge the holes at the ends of the outer shell to obtain the metal carrier. Step S3, High-temperature oxidation: The metal carrier is placed in a high-temperature furnace and calcined at 500°C for 5 hours to form a dense oxide film protective layer on the outer layer of the metal. Step S4, Catalyst Coating: To prevent the catalyst slurry from coating the non-expansion liner, use a collar to first cover the non-expansion liner. Coat the catalyst slurry onto the inner core of the metal carrier. Specifically, place the metal carrier on a balance, weigh 250±2.5g of catalyst slurry, transfer the metal carrier to the coating machine, adjust the negative pressure to 10kPa, extract, and dry and cool after the first coating is completed. Repeat the above steps on the other end (adjust the negative pressure to 11kPa) to complete the second coating. Step S5: After drying the coated metal support, calcine it at 550°C for 2 hours, and then cool it to obtain a metal support with improved catalytic activity.

[0056] Catalytic activity testing and comparison: The coated metal carrier was wire-cut into cylindrical catalyst samples with a diameter of 11.2 mm and a length of 50 mm. Similarly, the same catalyst slurry formulation was coated onto a commercially available conventional straight-through metal carrier using the same coating process, and then cut into catalyst samples of the same size. After washing, the activity of the catalyst samples was tested and compared under the same test conditions.

[0057] Secure with clasp welding: Add retaining rings (diameter) to both ends of the metal carrier. The final product can be obtained by welding. During welding, the retaining ring should be welded to the metal outer shell, not to the inner core of the metal carrier, to avoid burning through the metal carrier.

[0058] Test results: At an air-fuel ratio λ = 0.98, the catalytic activity of the metal support from Example 1 was compared with that of a conventional straight-through metal support. The conditions for both experiments were controlled as follows: space velocity (GHSV) = 40000 h⁻¹. -1 The gas mixture consisted of: NO: 560 ppm, CO: 3.2%, HC: 3100 ppm, CO2: 10.5%, O2: 2%, H2O: 10%, with the remainder being the equilibrium gas N2. The catalytic conversion efficiencies of CO, NO, and HC were tested at inlet temperatures of 280℃, 350℃, 450℃, and 550℃. The test results are shown in Table 1 below. Table 1. Comparison of catalytic activity between metal supports and conventional direct-flow metal supports at an air-fuel ratio λ=0.98 At an air-fuel ratio λ = 1.00, the catalytic activity of the metal support from Example 1 was compared with that of a conventional straight-through metal support. The conditions for both experiments were controlled as follows: space velocity (GHSV) = 40000 h⁻¹. -1 The gas mixture consisted of: NO: 560 ppm, CO: 3.2%, HC: 3100 ppm, CO2: 10.5%, O2: 2%, H2O: 10%, with the remainder being the equilibrium gas N2. The catalytic conversion efficiencies of CO, NO, and HC were tested at inlet temperatures of 280℃, 350℃, 450℃, and 550℃. The test results are shown in Table 2 below. Table 2. Comparison of catalytic activity between metal supports and conventional direct-flow metal supports at an air-fuel ratio λ=1.00 At an air-fuel ratio λ = 1.02, the catalytic activity of the metal support from Example 1 was compared with that of a conventional straight-through metal support. The conditions for both experiments were controlled as follows: space velocity (GHSV) = 40000 h⁻¹. -1 The gas mixture consisted of: NO: 560 ppm, CO: 3.2%, HC: 3100 ppm, CO2: 10.5%, O2: 2%, H2O: 10%, with the remainder being the equilibrium gas N2. The catalytic conversion efficiencies of CO, NO, and HC were tested at inlet temperatures of 280℃, 350℃, 450℃, and 550℃. The test results are shown in Table 3 below. Table 3. Comparison of catalytic activity between metal supports and conventional direct-flow metal supports at an air-fuel ratio λ=1.02 The test results show that, when the air-fuel ratio λ=1.00, the metal carrier of Example 1 has a CO conversion rate (at an inlet air temperature of 450°C) ≥90%, a NOx conversion rate (at an inlet air temperature of 450°C) ≥90%, and an HC conversion rate (at an inlet air temperature of 450°C) ≥90%. Moreover, the HC conversion rate is better than that of conventional straight-through metal carriers. Currently, the limits for HC emissions are higher, and the metal carrier of this invention is more suitable for application scenarios with higher requirements for HC conversion rates.

[0059] The technical principles of the present invention have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of the invention and should not be construed as limiting the scope of protection of the invention in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of the invention without inventive effort, and these embodiments will all fall within the scope of protection of the present invention.

Claims

1. A metal support for enhancing catalytic activity, characterized in that, The device includes a cylindrical outer shell and a metal carrier core fixed inside the outer shell. The metal carrier core is cylindrical and includes multiple corrugated plates. The corrugated plates have a periodic sinusoidal waveform structure along the radial direction of the metal carrier core and extend along the axial direction of the metal carrier core. Adjacent corrugated plates are stacked and brazed together in a staggered manner along the radial direction of the metal carrier core. Multiple non-linear gas flow channels extending along the axial direction of the metal carrier core are formed between adjacent corrugated plates. The corrugated plate has a through hole along its surface, and two adjacent gas flow channels are connected by the through hole so that when the gas enters the inner core of the metal carrier, it moves synchronously along the extension direction of the gas flow channel and along the radial direction of the inner core of the metal carrier.

2. The metal support for enhancing catalytic activity according to claim 1, characterized in that, The connecting hole is opened at the contact point of two adjacent corrugated plates that are stacked in a staggered manner.

3. The metal support for enhancing catalytic activity according to claim 2, characterized in that, The corrugated plate bends and extends along the axial direction of the inner core of the metal carrier to form an S-shaped meandering structure. The meandering paths of two adjacent corrugated plates cooperate with each other, and the gas flow channel extends in an S-shape along the axial direction of the inner core of the metal carrier.

4. The metal support for enhancing catalytic activity according to claim 3, characterized in that, The corrugated plate has multiple bends along the axial direction of the inner core of the metal carrier, and the connecting hole is opened at the bend.

5. The metal support for enhancing catalytic activity according to claim 3, characterized in that, The corrugated plate extends periodically along the axial direction of the inner core of the metal carrier, and the connecting holes are periodically and uniformly arranged along the meandering path of the corrugated plate.

6. The metal support for enhancing catalytic activity according to claim 1, characterized in that, When two adjacent corrugated plates are stacked, the waveform of the upper corrugated plate has a phase difference of 45° relative to the waveform of the lower corrugated plate.

7. The metal support for enhancing catalytic activity according to claim 6, characterized in that, The peak height L1 of the corrugated plate is 1.3 mm, and the peak width L2 is 2.8 mm.

8. The metal support for enhancing catalytic activity according to claim 1, characterized in that, The thickness of the corrugated plate is 0.1 to 0.15 mm.

9. The metal support for enhancing catalytic activity according to claim 1, characterized in that, The shape of the connecting hole can be racetrack-shaped, circular, elliptical, or polygonal.

10. A method for preparing a metal support to enhance catalytic activity, characterized in that, The method for preparing a metal support with enhanced catalytic activity as described in any one of claims 1 to 9 comprises the following steps: Step S1: Fabrication of the metal carrier core: The corrugated plate is installed into the mold for splicing, welding powder is sprayed, and then high-temperature brazing is performed. After cleaning and drying, the metal carrier core is obtained. Step S2, encapsulation of the metal carrier core: the metal carrier core is wrapped with a non-expansion gasket and pressed into the outer shell. The middle part of the outer shell is spun and the ends of the outer shell are enlarged to obtain the metal carrier. Step S3, High-temperature oxidation: The metal support is calcined; Step S4, Catalyst Coating: Coating the catalyst slurry onto the inner core of the metal carrier of the metal carrier; Step S5: After drying the coated metal support, calcine it and cool it to obtain a metal support with improved catalytic activity.

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