A device and catalyst suitable for combustible gas treatment in tail gas of carbonization furnace of battery negative electrode material

Abstract

The application discloses a device and a catalyst suitable for combustible gas treatment in tail gas of a carbonization furnace of a battery negative electrode material, and relates to the technical field of catalysts. The device comprises a body, a catalyst arranged in the body, heating wires wound on the outer surface of the catalyst, shells arranged on the two sides of the body, and pipelines arranged on the outer sides of the shells. Compared with a traditional single-layer catalyst, the catalyst has obviously improved anti-poisoning performance and good activity recovery after regeneration.

Description

Technical Field

[0001] This invention relates to the field of exhaust gas treatment technology, and specifically to a device and catalyst suitable for treating combustible gases in the exhaust gas of a battery negative electrode material carbonization furnace. Background Technology

[0002] Carbon materials suitable for lithium-ion batteries and sodium-ion batteries include hard carbon, soft carbon, carbon nanotubes, activated carbon, and graphite. Carbonization is the key process for synthesizing carbon materials from these materials and is often carried out in a carbonization furnace. There are many types of carbonization furnaces, including rotary kilns, tunnel kilns, graphitization furnaces, and CVD furnaces. Generally, inert or reducing gases are introduced into the carbonization furnace, and the furnace temperature is strictly controlled to keep the carbon material precursor in a high-temperature and oxygen-deficient atmosphere. The graphitization process involves heating the carbon material precursor to above 2500-3000℃, which transforms the amorphous and disordered carbon structure into an ordered graphite crystalline structure. The carbonization temperature for the preparation of other carbon materials is generally lower, usually in the range of 500-1600℃, which is closely related to the carbon material precursor used. The precursors used in the preparation of battery anode materials generally come from several sources: (1) biomass, mainly including fruit shells, starch, sucrose, straw, wood, etc. (2) Organic polymers, mainly including phenolic resins, cellulose, polyaniline, etc. (3) Fossil fuels, including coal and asphalt, etc. The reaction mechanism in the pyrolysis process of carbon material precursors is a very complex process and is closely related to the type of carbon material precursor. For example, phenolic resins may undergo dehydrogenation, condensation, hydrogen transfer and isomerization simultaneously during pyrolysis, releasing various gases such as H2, CH4, CO, H2O and CO2. For fossil fuels, the raw materials contain sulfur, and the tail gas also contains some SO2 and H2S. At the same time, a large amount of dust is generated during carbonization. Most of the gases emitted by the carbonization furnace are toxic, harmful or dangerous. If they are not purified, they will not only cause environmental pollution, but also bring huge safety hazards to production. Since inert gas is often introduced for protection during the carbon material production process, the exhaust gas is a combustion-rich and oxygen-deficient atmosphere. Under an oxygen-deficient atmosphere, H2, CH4 and CO cannot be fully burned, and problems such as carbon poisoning will occur. When oxygen is sufficient, H2 and CO gases are easily burned off; however, methane is the most stable hydrocarbon compound, and ordinary catalysts cannot achieve complete conversion. Patent CN200420062542.3 proposes a pollution control device combining secondary air injection and catalytic converter technology. Secondary air injection can provide sufficient oxygen to effectively purify exhaust gases emitted from motorcycle engines. However, motorcycle exhaust gases are mainly non-methane gases, making motorcycle exhaust purification catalysts unsuitable. Furthermore, the presence of large amounts of SO2 in the carbonization furnace exhaust gas can lead to sulfur poisoning of the catalyst, and conventional motorcycle exhaust purification catalysts cannot meet lifespan requirements. Currently used industrial catalysts are expensive and complex to install and replace. Given the specific production process of battery negative electrode materials, a catalyst needs to be specifically designed to fully purify toxic and harmful flammable gases, while ensuring a long lifespan and easy installation and replacement. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a device and catalyst suitable for treating combustible gases in the tail gas of a carbonization furnace for battery anode materials. It has high combustion efficiency, long service life and is easy to replace. Compared with traditional single-layer catalysts, its anti-poisoning performance is significantly improved and its activity is well restored after regeneration.

[0004] To address the aforementioned technical problems, this invention provides a device for treating combustible gases in the exhaust gas of a carbonization furnace for battery negative electrode materials. The device includes a main body, a catalyst disposed within the main body, a heating wire wound around the outer surface of the catalyst, outer shells on both sides of the main body, and pipes disposed on the outer sides of the outer shells.

[0005] Furthermore, a detachable clamp is provided at the connection point between the main body and the outer shell.

[0006] Furthermore, one of the pipes is equipped with an air pump and an air supply port.

[0007] Furthermore, it includes a temperature sensor in contact with the catalyst.

[0008] A method for preparing a catalyst includes the following steps:

[0009] (1) Bottom layer: Take composite oxide material A1, composite oxide material A2, binder and water into a ball mill jar, place it on a horizontal ball mill, and ball mill at a certain speed. Then add precious metal solution to the slurry and ball mill at a certain speed to obtain slurry S1;

[0010] Slurry S1 is coated onto a honeycomb carrier to obtain a catalyst semi-finished product. The catalyst semi-finished product is then transferred to a drying oven and dried at a certain temperature.

[0011] (2) Upper layer: Take composite oxide material A3, binder and water into a ball mill jar, place it on a horizontal ball mill, and ball mill at a certain speed. Then add precious metal solution to the slurry and ball mill at a certain speed to obtain slurry S2.

[0012] The slurry S2 is coated onto the honeycomb carrier that has already been coated with the first coating to obtain the finished catalyst. It is then transferred to a drying oven and dried at a certain temperature. Finally, it is transferred to a muffle furnace and calcined at a certain temperature to obtain the shaped catalyst.

[0013] The beneficial effects of the present invention are: 1. The catalyst and device of the present invention have the characteristics of high combustion efficiency, long service life and easy replacement;

[0014] 2. Compared with traditional single-layer catalysts, bilayer catalysts have significantly improved resistance to poisoning and good activity recovery after regeneration. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the device structure of the present invention.

[0016] Figure 2 This is a schematic diagram of the catalyst structure of the present invention.

[0017] Figure 3 This is a graph showing the experimental data of the present invention.

[0018] The labels in the diagram are as follows: 1. Air pump; 2. Air inlet; 3. Temperature sensor; 4. Clamp; 5. Heating wire; 6. Catalyst; 7. Housing; 8. Pipe. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0020] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0022] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0023] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0024] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0025] Reference Figures 1 to 2 As shown, the present invention includes a main body, a catalyst 6 is disposed inside the main body, a heating wire 5 is wound around the outer surface of the catalyst 6, outer shells 7 are disposed on both sides of the main body, pipes 8 are disposed on the outer side of the outer shells 7, a detachable clamp 4 is disposed at the connection between the main body and the outer shells 7, an air pump 1 and an air inlet 2 are disposed on one of the pipes 8, and the device also includes a temperature sensor 3 in contact with the catalyst 6.

[0026] The catalyst preparation method is as follows: (1) Bottom layer: Take composite oxide material A1, composite oxide material A2, binder and water into a ball mill jar, place it on a horizontal ball mill, and ball mill at a certain speed. Then add noble metal solution to the slurry and ball mill at a certain speed to obtain slurry S1;

[0027] Slurry S1 is coated onto a honeycomb carrier to obtain a catalyst semi-finished product. The catalyst semi-finished product is then transferred to a drying oven and dried at a certain temperature.

[0028] (2) Upper layer: Take composite oxide material A3, binder and water into a ball mill jar, place it on a horizontal ball mill, and ball mill at a certain speed. Then add precious metal solution to the slurry and ball mill at a certain speed to obtain slurry S2.

[0029] The slurry S2 is coated onto the honeycomb carrier that has already been coated with the first coating to obtain the finished catalyst. It is then transferred to a drying oven and dried at a certain temperature. Finally, it is transferred to a muffle furnace and calcined at a certain temperature to obtain the shaped catalyst.

[0030] The specific operation methods of each embodiment are as follows:

[0031] Example 1:

[0032] The catalyst was designed with a double layer. (1) Bottom layer: CeO2 (40wt%)-ZrO2 (60wt%) (20g / L), SiO2 (30wt%)-Al2O3 (70wt%) (80g / L), aluminum sol (containing 5g / L Al2O3) and water were placed in a ball mill jar, placed on a horizontal ball mill, and the speed was adjusted to 300rpm for 1h. Then, platinum nitrate solution (containing 0.5g / L Pt) and palladium nitrate solution (containing 2g / L Pd) were added to the slurry, the speed was adjusted to 300rpm, and the slurry was ball milled for 1h to obtain the slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of Φ1”*2” (200 mesh) to obtain the catalyst semi-finished product. The catalyst semi-finished product was transferred to a drying oven and dried at 100℃ for 5h. (2) Upper layer: Take CeO2 (40wt%)-ZrO2 (50wt%)-TiO2 (10wt%) (60g / L), aluminum sol (containing Al2O3 3g / L) and water into a ball mill jar, place it on a horizontal ball mill, adjust the speed to 300rpm, and ball mill for 1h to obtain slurry S2. Coat slurry S2 onto a Φ1”*2” (300 mesh) cylindrical cordierite carrier to obtain a catalyst semi-finished product. Transfer the catalyst semi-finished product to a muffle furnace, dry it at 100℃ for 5h, and then calcine it at 550℃ for 3h to obtain the catalyst finished product, catalyst code C-1.

[0033] Example 2:

[0034] The catalyst was designed with a double layer. (1) Bottom layer: CeO2 (40wt%)-ZrO2 (60wt%) (20g / L), SiO2 (30wt%)-Al2O3 (70wt%) (80g / L), aluminum sol (containing 5g / L Al2O3) and water were placed in a ball mill jar, placed on a horizontal ball mill, and the speed was adjusted to 300rpm for 1h. Then, platinum nitrate solution (containing 0.5g / L Pt) and palladium nitrate solution (containing 2g / L Pd) were added to the slurry, the speed was adjusted to 300rpm, and the slurry was ball milled for 1h to obtain the slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of Φ1”*2” (200 mesh) to obtain the catalyst semi-finished product. The catalyst semi-finished product was transferred to a drying oven and dried at 100℃ for 5h. (2) Upper layer: Take CeO2 (40wt%)-ZrO2 (50wt%)-TiO2 (10wt%) (20g / L), aluminum sol (containing Al2O3 3g / L) and water into a ball mill jar, place it on a horizontal ball mill, adjust the speed to 300rpm, and ball mill for 1h to obtain a slurry. Coat the slurry onto a Φ1”*2” (300 mesh) cylindrical cordierite carrier to obtain a catalyst semi-finished product. Transfer the catalyst semi-finished product to a muffle furnace, dry it at 100℃ for 5h, and then calcine it at 550℃ for 3h to obtain the catalyst finished product, catalyst code C-2.

[0035] Example 3:

[0036] The catalyst was designed with a double layer. (1) Bottom layer: CeO2 (40wt%)-ZrO2 (60wt%) (20g / L), SiO2 (30wt%)-Al2O3 (70wt%) (80g / L), aluminum sol (containing 5g / L Al2O3) and water were placed in a ball mill jar, placed on a horizontal ball mill, and the speed was adjusted to 300rpm for 1h. Then, platinum nitrate solution (containing 0.5g / L Pt) and palladium nitrate solution (containing 2g / L Pd) were added to the slurry, the speed was adjusted to 300rpm, and the slurry was ball milled for 1h to obtain the slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of Φ1”*2” (200 mesh) to obtain the catalyst semi-finished product. The catalyst semi-finished product was transferred to a drying oven and dried at 100℃ for 5h. (2) Upper layer: Take CeO2 (40wt%)-ZrO2 (50wt%)-TiO2 (10wt%) (100g / L), aluminum sol (containing Al2O3 3g / L) and water into a ball mill jar, place it on a horizontal ball mill, adjust the speed to 300rpm, and ball mill for 1h to obtain a slurry. Coat the slurry onto a Φ1”*2” (300 mesh) cylindrical cordierite carrier to obtain a catalyst semi-finished product. Transfer the catalyst semi-finished product to a muffle furnace, dry it at 100℃ for 5h, and then calcine it at 550℃ for 3h to obtain the catalyst finished product, catalyst code C-3.

[0037] Example 4:

[0038] The catalyst was designed with a double layer. (1) Bottom layer: CeO2 (40wt%)-ZrO2 (60wt%) (20g / L), SiO2 (30wt%)-Al2O3 (70wt%) (80g / L), aluminum sol (containing 5g / L Al2O3) and water were placed in a ball mill jar, placed on a horizontal ball mill, and the speed was adjusted to 300rpm for 1h. Then, platinum nitrate solution (containing 0.5g / L Pt) and palladium nitrate solution (containing 2g / L Pd) were added to the slurry, the speed was adjusted to 300rpm, and the slurry was ball milled for 1h to obtain the slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of Φ1”*2” (200 mesh) to obtain the catalyst semi-finished product. The catalyst semi-finished product was transferred to a drying oven and dried at 100℃ for 5h. (2) Upper layer: Take CeO2 (40wt%)-ZrO2 (50wt%)-TiO2 (10wt%) (60g / L), aluminum sol (containing Al2O3 3g / L) and water into a ball mill jar, place it on a horizontal ball mill, adjust the speed to 300rpm, and ball mill for 1h to obtain a slurry. Coat the slurry onto a Φ1”*2” (300 mesh) cylindrical cordierite carrier to obtain a catalyst semi-finished product. Transfer the catalyst semi-finished product to a muffle furnace, dry it at 100℃ for 5h, and then calcine it at 550℃ for 3h to obtain the catalyst finished product, catalyst code C-4.

[0039] Example 5:

[0040] The catalyst was designed with a double layer. (1) Bottom layer: CeO2 (40wt%)-ZrO2 (60wt%) (20g / L), SiO2 (30wt%)-Al2O3 (70wt%) (80g / L), aluminum sol (containing 5g / L Al2O3) and water were placed in a ball mill jar, placed on a horizontal ball mill, and the speed was adjusted to 300rpm for 1h. Then, platinum nitrate solution (containing 0.5g / L Pt) and palladium nitrate solution (containing 2g / L Pd) were added to the slurry, the speed was adjusted to 300rpm, and the slurry was ball milled for 1h to obtain the slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of Φ1”*2” (200 mesh) to obtain the catalyst semi-finished product. The catalyst semi-finished product was transferred to a drying oven and dried at 100℃ for 5h. (2) Upper layer: Take CeO2 (40wt%)-ZrO2 (50wt%)-La2O3 (10wt%) (60g / L), aluminum sol (containing Al2O3 3g / L) and water into a ball mill jar, place it on a horizontal ball mill, adjust the speed to 300rpm, and ball mill for 1h to obtain a slurry. Coat the slurry onto a Φ1”*2” (300 mesh) cylindrical cordierite carrier to obtain a catalyst semi-finished product. Transfer the catalyst semi-finished product to a muffle furnace, dry it at 100℃ for 5h, and then calcine it at 550℃ for 3h to obtain the catalyst finished product, catalyst code C-5.

[0041] Example 6:

[0042] The catalyst was designed with a double layer. (1) Bottom layer: CeO2 (40wt%)-ZrO2 (60wt%) (100g / L), aluminum sol (containing Al2O3 5g / L) and water were placed in a ball mill jar, placed on a horizontal ball mill, and the speed was adjusted to 300rpm for 1h. Then, platinum nitrate solution (containing Pt 0.5g / L) and palladium nitrate solution (containing Pd 2g / L) were added to the slurry, and the speed was adjusted to 300rpm for 1h to obtain the slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of Φ1”*2” (200 mesh) to obtain the catalyst semi-finished product. The catalyst semi-finished product was transferred to a drying oven and dried at 100℃ for 5h. (2) Upper layer: CeO2 (40wt%)-ZrO2 (50wt%)-TiO2 (10wt%) (60g / L), aluminum sol (containing Al2O3 3g / L) and water were placed in a ball mill jar and placed on a horizontal ball mill. The speed was adjusted to 300 rpm and the mixture was milled for 1 hour. Then, platinum nitrate solution (containing Pt 0.5g / L) and palladium nitrate solution (containing Pd 2g / L) were added to the slurry. The speed was adjusted to 300 rpm and the mixture was milled for 1 hour to obtain a slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of 1”*2” (300 mesh) to obtain a catalyst semi-finished product. The catalyst semi-finished product was transferred to a muffle furnace, dried at 100℃ for 5 hours, and then calcined at 550℃ for 3 hours to obtain the catalyst finished product, catalyst code C-6.

[0043] Example 7:

[0044] The catalyst was designed with a double layer. (1) Bottom layer: SiO2 (30wt%)-Al2O3 (70wt%) (100g / L), aluminum sol (containing 5g / L Al2O3) and water were placed in a ball mill jar, placed on a horizontal ball mill, and the speed was adjusted to 300rpm for 1h. Then, platinum nitrate solution (containing 0.5g / L Pt) and palladium nitrate solution (containing 2g / L Pd) were added to the slurry, the speed was adjusted to 300rpm, and the slurry was ball milled for 1h to obtain the slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of Φ1”*2” (200 mesh) to obtain the catalyst semi-finished product. The catalyst semi-finished product was transferred to a drying oven and dried at 100℃ for 5h. (2) Upper layer: Take CeO2 (40wt%)-ZrO2 (50wt%)-TiO2 (10wt%) (60g / L), aluminum sol (containing Al2O3 3g / L) and water into a ball mill jar, place it on a horizontal ball mill, adjust the speed to 300rpm, and ball mill for 1h to obtain a slurry. Coat the slurry onto a Φ1”*2” (300 mesh) cylindrical cordierite carrier to obtain a catalyst semi-finished product. Transfer the catalyst semi-finished product to a muffle furnace, dry it at 100℃ for 5h, and then calcine it at 550℃ for 3h to obtain the catalyst finished product, catalyst code C-7.

[0045] Example 8:

[0046] The catalyst was designed with a double layer. (1) Bottom layer: CeO2 (40wt%)-ZrO2 (60wt%) (20g / L), SiO2 (30wt%)-Al2O3 (70wt%) (80g / L), aluminum sol (containing 5g / L Al2O3) and water were placed in a ball mill jar, placed on a horizontal ball mill, and the speed was adjusted to 300rpm for 1h. Then, platinum nitrate solution (containing 0.5g / L Pt) and palladium nitrate solution (containing 2g / L Pd) were added to the slurry, the speed was adjusted to 300rpm, and the slurry was ball milled for 1h to obtain the slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of Φ1”*2” (200 mesh) to obtain the catalyst semi-finished product. The catalyst semi-finished product was transferred to a drying oven and dried at 100℃ for 5h. (2) Upper layer: Take β molecular sieve (silicon-to-aluminum ratio = 30) (60 g / L), alumina sol (containing Al2O3 3 g / L) and water into a ball mill jar, place it on a horizontal ball mill, adjust the speed to 300 rpm, and ball mill for 1 h to obtain a slurry. Coat the slurry onto a Φ1”*2” (300 mesh) cylindrical cordierite carrier to obtain a catalyst semi-finished product. Transfer the catalyst semi-finished product to a muffle furnace, dry it at 100℃ for 5 h, and then calcine it at 550℃ for 3 h to obtain the catalyst finished product, catalyst code C-8.

[0047] Example 9:

[0048] The catalyst was designed with a double layer. (1) Bottom layer: CeO2 (40wt%)-ZrO2 (60wt%) (20g / L), SiO2 (30wt%)-Al2O3 (70wt%) (80g / L), aluminum sol (containing 5g / L Al2O3) and water were placed in a ball mill jar, placed on a horizontal ball mill, and the speed was adjusted to 300rpm for 1h. Then, platinum nitrate solution (containing 0.5g / L Pt) and palladium nitrate solution (containing 2g / L Pd) were added to the slurry, the speed was adjusted to 300rpm, and the slurry was ball milled for 1h to obtain the slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of Φ1”*2” (200 mesh) to obtain the catalyst semi-finished product. The catalyst semi-finished product was transferred to a drying oven and dried at 100℃ for 5h. (2) Upper layer: Take β molecular sieve (silicon-to-aluminum ratio = 130) (60 g / L), alumina sol (containing Al2O3 3 g / L) and water into a ball mill jar, place it on a horizontal ball mill, adjust the speed to 300 rpm, and ball mill for 1 h to obtain a slurry. Coat the slurry onto a Φ1”*2” (300 mesh) cylindrical cordierite carrier to obtain a catalyst semi-finished product. Transfer the catalyst semi-finished product to a muffle furnace, dry it at 100℃ for 5 h, and then calcine it at 550℃ for 3 h to obtain the catalyst finished product, catalyst code C-9.

[0049] Example 10:

[0050] The catalyst was designed with a double layer. (1) Bottom layer: CeO2 (40wt%)-ZrO2 (60wt%) (20g / L), SiO2 (30wt%)-Al2O3 (70wt%) (80g / L), aluminum sol (containing 5g / L Al2O3) and water were placed in a ball mill jar, placed on a horizontal ball mill, and the speed was adjusted to 300rpm for 1h. Then, platinum nitrate solution (containing 0.5g / L Pt) and palladium nitrate solution (containing 2g / L Pd) were added to the slurry, the speed was adjusted to 300rpm, and the slurry was ball milled for 1h to obtain the slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of Φ1”*2” (200 mesh) to obtain the catalyst semi-finished product. The catalyst semi-finished product was transferred to a drying oven and dried at 100℃ for 5h. (2) Upper layer: Take β molecular sieve (silicon-to-aluminum ratio = 600) (60 g / L), alumina sol (containing Al2O3 3 g / L) and water into a ball mill jar, place it on a horizontal ball mill, adjust the speed to 300 rpm, and ball mill for 1 h to obtain a slurry. Coat the slurry onto a Φ1”*2” (300 mesh) cylindrical cordierite carrier to obtain a catalyst semi-finished product. Transfer the catalyst semi-finished product to a muffle furnace, first dry it at 100℃ for 5 h, and then calcine it at 550℃ for 3 h to obtain the catalyst finished product, catalyst code C-10.

[0051] Example 11:

[0052] The catalyst was designed with a double layer. (1) Bottom layer: CeO2 (40wt%)-ZrO2 (60wt%) (20g / L), SiO2 (30wt%)-Al2O3 (70wt%) (80g / L), aluminum sol (containing 5g / L Al2O3) and water were placed in a ball mill jar, placed on a horizontal ball mill, and the speed was adjusted to 300rpm for 1h. Then, platinum nitrate solution (containing 0.5g / L Pt) and palladium nitrate solution (containing 2g / L Pd) were added to the slurry, the speed was adjusted to 300rpm, and the slurry was ball milled for 1h to obtain the slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of Φ1”*2” (200 mesh) to obtain the catalyst semi-finished product. The catalyst semi-finished product was transferred to a drying oven and dried at 100℃ for 5h. (2) Upper layer: Take ZSM-5 molecular sieve (silicon-to-aluminum ratio = 40) (60 g / L), alumina sol (containing Al2O3 3 g / L) and water into a ball mill jar, place it on a horizontal ball mill, adjust the speed to 300 rpm, and ball mill for 1 h to obtain a slurry. Coat the slurry onto a Φ1”*2” (300 mesh) cylindrical cordierite carrier to obtain a catalyst semi-finished product. Transfer the catalyst semi-finished product to a muffle furnace, first dry it at 100℃ for 5 h, and then calcine it at 550℃ for 3 h to obtain the catalyst finished product, catalyst code C-11.

[0053] Example 12:

[0054] The catalyst was designed with a double layer. (1) Bottom layer: CeO2 (40wt%)-ZrO2 (60wt%) (20g / L), SiO2 (30wt%)-Al2O3 (70wt%) (80g / L), aluminum sol (containing 5g / L Al2O3) and water were placed in a ball mill jar, placed on a horizontal ball mill, and the speed was adjusted to 300rpm for 1h. Then, platinum nitrate solution (containing 0.5g / L Pt) and palladium nitrate solution (containing 2g / L Pd) were added to the slurry, the speed was adjusted to 300rpm, and the slurry was ball milled for 1h to obtain the slurry. The slurry was coated onto a cylindrical cordierite support with a diameter of Φ1”*2” (200 mesh) to obtain the catalyst semi-finished product. The catalyst semi-finished product was transferred to a drying oven and dried at 100℃ for 5h. (2) Upper layer: Take SSZ-13 molecular sieve (silicon-to-aluminum ratio = 40) (60 g / L), alumina sol (containing Al2O3 3 g / L) and water into a ball mill jar, place it on a horizontal ball mill, adjust the speed to 300 rpm, and ball mill for 1 hour to obtain a slurry. Coat the slurry S2 onto a Φ1”*2” (300 mesh) cylindrical cordierite carrier to obtain a catalyst semi-finished product. Transfer the catalyst semi-finished product to a muffle furnace, first dry it at 100℃ for 5 hours, and then calcine it at 550℃ for 3 hours to obtain the catalyst finished product, catalyst code C-12.

[0055] Comparative Example 1: The top layer of Example 1 was removed, leaving only the bottom layer. Catalyst code CC-1.

[0056] Comparative Example 2: Industrial catalyst containing 1 g / L Pt and 2 g / L Pd, with a total coating amount of 111 g / L. Catalyst code CC-1.

[0057] Test Example: (1) Catalyst Performance Test: Fresh catalyst products from the Examples and Comparative Examples were loaded into the catalyst reaction apparatus. The reaction atmosphere introduced into the catalyst was: CO 5000ppm, CH4 500ppm, O2 10%, H2O 10%, with N2 as the balance gas and a test space velocity of 20,000 h⁻¹. -1 The temperature is increased from room temperature at a rate of 5°C / min. -1 The complete conversion temperature (T) of the catalyst when the conversion rate of CO and CH4 is 90% was tested. 90 (2) Catalyst poisoning: A poisoning experiment was conducted on a catalyst that had undergone performance testing. 10 ppm SO2 was then introduced into the reaction atmosphere for 20 hours. The complete conversion temperature (T0) at which the catalyst achieved a 90% conversion rate for CO and CH4 was determined. 90(3) Catalyst regeneration: The catalyst that had undergone the catalyst poisoning experiment was regenerated. The regeneration conditions were: CO 5000ppm, CH4 500ppm, H2O 10%, equilibrium gas was N2, O2 concentration fluctuated between 4800ppm and 7200ppm at 0.5Hz, regeneration temperature was 700℃, and duration was 1h. After regeneration, the complete conversion temperature (T) of the catalyst when the conversion rate of CO and CH4 was 90% was tested. 90 ).

[0058] Test results are available Figure 3 .

[0059] In summary, the production process of carbon materials for lithium-ion and sodium-ion batteries generates flammable gases such as H2, CH4, and CO, which can easily pose safety hazards if leaked. The traditional approach is to use oxidizing catalysts to burn these gases. However, the exhaust gas often contains both H2O and SO2, which can easily cause sulfur poisoning, especially affecting the conversion rates of CH4 and CO, while H2 is highly flammable. Current industrial catalysts, while considering the purification of flammable gases like CH4 and CO, neglect the catalyst poisoning problem caused by H2O and SO2, and are also expensive and have short lifespans. Furthermore, they generally employ integrated exhaust gas aftertreatment systems, making replacement and maintenance difficult. This patent designs a device and catalyst suitable for treating flammable gases in the exhaust gas of a battery anode material carbonization furnace, offering advantages such as high combustion efficiency, long service life, and easy replacement. As shown in Table 1, a comparison between Example 1 and Comparative Example 1 reveals that the double-layer catalyst of this patent, compared to the traditional single-layer catalyst, exhibits a slight decrease in fresh performance but a significant improvement in resistance to poisoning, and its activity is well restored after regeneration. A comparison of the examples and comparative example 2 reveals that the bilayer catalyst of this patent invention performs better than most industrial catalysts, especially in terms of resistance to poisoning and regeneration capacity.

[0060] This patent adds a blank layer without precious metals on top of the traditional precious metal layer, effectively protecting the underlying precious metal coating from poisoning. When poisons come into contact with the catalyst surface, most are adsorbed or repelled by the surface layer and cannot penetrate the underlying precious metal coating. However, the performance of the catalyst is closely related to the type of the upper protective layer material, the amount of the upper protective layer material, and the type of the underlying precious metal coating material. A comparison of Examples 1-3 shows that there is an optimal range for the amount of upper protective layer material. Too little material cannot provide effective protection, while too much material prevents CH4 and CO from penetrating the underlying layer, thus inhibiting catalyst activity. A comparison of Examples 1, 4, and 5 shows that adding TiO2 to the upper protective layer material is more effective than using Al2O3 and La2O3. This is because TiO2 is more acidic, and a strongly acidic support has weak adsorption of sulfur, which helps to inhibit sulfur poisoning of the catalyst. A comparison of Examples 1, 6, and 7 shows that using a mixture of CeZrO and SiAlO materials in the underlying layer is more effective than using a single material because of their synergistic effect. CeZrO can provide active oxygen for noble metals, while SiAlO can effectively regulate the valence state of PtPd. A comparison of Examples 8 to 12 revealed that using a molecular sieve in the upper layer can effectively suppress catalyst poisoning, and the protective effect becomes stronger with increasing silicon-to-aluminum ratio.

[0061] The above-described embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the claims.

Claims

1. A method for preparing a catalyst for treating combustible gases in the off-gas of a carbonization furnace for battery anode materials, characterized by, Comprise the following steps: (1) bottom layer: take the composite oxide material A1, composite oxide material A2, binder and water in the ball mill tank, put on the horizontal ball mill, carry on the ball grinding under certain rotating speed, then add noble metal solution to the slurry, carry on the ball grinding under certain rotating speed, obtain slurry S1; Slurry S1 is coated on the honeycomb carrier to obtain a catalyst semi-finished product, which is transferred to a drying box and dried at a certain temperature; (2) upper layer: take the composite oxide material A3, binder and water in the ball mill tank, put on the horizontal ball mill, carry on the ball grinding under certain rotating speed, then add noble metal solution to the slurry, carry on the ball grinding under certain rotating speed, obtain slurry S2; Slurry S2 is coated on the honeycomb carrier which has been coated with the first coating to obtain a catalyst finished product, which is then transferred to a drying box and dried at a certain temperature, and finally transferred to a muffle furnace and calcined at a certain temperature to obtain a shaped catalyst.

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