Engine exhaust treatment method and device

Abstract

The application discloses an engine exhaust treatment method and device. A target catalyst is obtained, and an active component of the target catalyst comprises cobalt Co, chromium Cr and indium In. The target catalyst is placed in a synergistic catalytic reactor. Then, engine exhaust containing CH4 and nitrogen oxide NO X is introduced into the synergistic catalytic reactor to perform exhaust treatment. During the exhaust treatment, CH4 is converted into carbon dioxide CO2 and water H2O, and NO X is converted into nitrogen N2 based on the action of the target catalyst. Finally, the engine exhaust after the exhaust treatment is discharged from the synergistic catalytic reactor. It can be seen that, for the engine exhaust containing CH4 and NO X , only the synergistic catalytic reactor is arranged as the exhaust treatment system, CH4 and NO X can be treated simultaneously under the action of the target catalyst, and the purposes of simultaneously removing CH4 and NO X are achieved. That is, a mode of synergistically treating CH4 and NO X by using one set of exhaust treatment system is provided, and the engine exhaust treatment system can be simplified, and the exhaust treatment cost is reduced.

Description

Technical Field

[0001] This application relates to the field of engine technology, and in particular to an engine exhaust gas treatment method and apparatus. Background Technology

[0002] Liquefied natural gas (LNG) is being used as an alternative fuel for engines to reduce particulate matter (PM) and sulfur oxides (SO). X LNG exhibits significant advantages in terms of emissions, and its lower carbon-to-hydrogen ratio (C / H) reduces carbon dioxide (CO2) emissions compared to diesel fuels. The widespread use of LNG is of great importance for improving my country's energy structure.

[0003] In practical applications, nitrogen oxides (NOx) are unavoidable in the exhaust gas of engines using LNG. X It produces emissions of NO, as well as a significant amount of methane (CH4) emissions. X Not only can it contribute to acid rain and photochemical smog, but it also seriously damages human health. CH4 is a greenhouse gas that contributes to the greenhouse effect. Therefore, it is necessary to target NO in exhaust gases. X It is used to treat CH4 emissions.

[0004] Among related technologies, a technical route combining selective catalytic reduction (SCR) and catalytic oxidation (mainly using MOC catalysts) is employed to remove NO. X And CH4. However, the exhaust gas treatment methods used in related technologies have high exhaust gas treatment costs. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides an engine exhaust gas treatment method and apparatus, which utilizes an exhaust gas treatment system to co-treat CH4 and NO. X This method simplifies the engine exhaust treatment system and reduces exhaust treatment costs.

[0006] The embodiments of this application disclose the following technical solutions:

[0007] On one hand, embodiments of this application provide an engine exhaust gas treatment method, the method comprising:

[0008] Obtain the target catalyst; the active components of the target catalyst include cobalt (Co), chromium (Cr), and indium (In);

[0009] The target catalyst is placed in a synergistic catalytic reactor;

[0010] Will contain methane (CH4) and nitrogen oxides (NO)X The engine exhaust gas is fed into the co-catalytic reactor for exhaust gas treatment;

[0011] During the exhaust gas treatment process, based on the action of the target catalyst, the CH4 is converted into carbon dioxide (CO2) and water (H2O), and the NO is converted into... X It is converted into nitrogen gas N2;

[0012] The engine exhaust gas, after being treated, is discharged from the co-catalytic reactor.

[0013] On the other hand, embodiments of this application provide an engine exhaust gas treatment device, the device including an acquisition unit, a placement unit, an inlet unit, a conversion unit, and an outlet unit:

[0014] The acquisition unit is used to acquire the target catalyst; the active components of the target catalyst include cobalt (Co), chromium (Cr), and indium (In);

[0015] The placement unit is used to place the target catalyst in the co-catalytic reactor;

[0016] The inlet unit is used to introduce methane (CH4) and nitrogen oxides (NO). X The engine exhaust gas is fed into the co-catalytic reactor for exhaust gas treatment;

[0017] The conversion unit is used, during the exhaust gas treatment process, to convert CH4 into carbon dioxide (CO2) and water (H2O) based on the action of the target catalyst, and to convert NO... X It is converted into nitrogen gas N2;

[0018] The discharge unit is used to discharge the engine exhaust gas, after exhaust gas treatment, from the co-catalytic reactor.

[0019] As can be seen from the above technical solution, for engine exhaust gas treatment, the target catalyst can first be obtained. The active components of this target catalyst include cobalt (Co), chromium (Cr), and indium (In), and the target catalyst is placed in a co-catalytic reactor. Then, gases containing CH4 and nitrogen oxides (NOx) can be treated. X The engine exhaust gas is fed into a co-catalytic reactor for exhaust gas treatment. During the treatment process, based on the action of the target catalyst, CH4 can be converted into carbon dioxide (CO2) and water (H2O), while NO is converted into CO2. X It is converted into nitrogen (N2). Finally, the engine exhaust gas, after treatment, can be discharged from the co-catalytic reactor. It can be seen that this is effective for gases containing CH4 and NO. X For engine exhaust gases, a single exhaust gas treatment system consisting of a co-catalytic reactor can be installed, which, under the action of the target catalyst, can simultaneously treat CH4 and NO. XThe process is performed to simultaneously remove CH4 and NO. X The purpose is to achieve the following: Compared to the removal methods in related technologies, this application, under the action of the target catalyst, requires only one exhaust gas treatment system to simultaneously remove CH4 and NO. X In other words, it provides a method for co-processing CH4 and NO. X This method simplifies the engine exhaust treatment system and reduces exhaust treatment costs. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 A flowchart of an engine exhaust gas treatment method provided in this application embodiment;

[0022] Figure 2 A schematic diagram illustrating the CH4 removal efficiency using a first catalyst, a second catalyst, and a target catalyst, provided for embodiments of this application;

[0023] Figure 3 The NO using a first catalyst, a second catalyst, and a target catalyst provided in the embodiments of this application X A diagram illustrating the removal efficiency;

[0024] Figure 4 This is a structural diagram of an engine exhaust gas treatment device provided in an embodiment of this application. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0026] For engine exhaust emissions from LNG-fueled engines, such as those in marine transportation vehicles, the following points are relevant. Marine engines typically employ a lean-burn strategy, resulting in a high concentration of O2 in the exhaust gases. This means the exhaust gases can be considered oxygen-rich. Under oxygen-rich conditions, three-way catalytic converters cannot be used to simultaneously process CH4 and NO. XGenerally, a combined SCR and MOC (Modular Oxidation) approach is adopted. However, this approach requires the installation of both an SCR system and an MOC system within the engine exhaust aftertreatment system, meaning two systems are needed. This makes the engine exhaust aftertreatment system more complex and costly. Furthermore, MOC uses a large amount of precious metal catalysts such as platinum, palladium, and rhodium, and the high amount of catalyst used significantly increases catalyst costs, resulting in higher economic costs.

[0027] Therefore, this application provides an engine exhaust gas treatment method and apparatus, which provides a method for co-treating CH4 and NO using an exhaust gas treatment system. X This method simplifies the engine exhaust treatment system and reduces exhaust treatment costs.

[0028] The engine exhaust gas treatment method provided in this application can be implemented using computer equipment, which can be a terminal device or a server. The server can be a standalone physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing cloud computing services. Terminal devices include, but are not limited to, mobile phones, computers, intelligent voice interaction devices, smart home appliances, and vehicle terminals. Terminal devices and servers can be directly or indirectly connected via wired or wireless communication, and this application does not impose any limitations in this regard.

[0029] The following examples illustrate this in detail:

[0030] Figure 1 A flowchart of an engine exhaust gas treatment method provided in this application embodiment is used as an example to illustrate the method, which includes S101-S105:

[0031] S101: Obtain the target catalyst.

[0032] In engine exhaust gas treatment, a target catalyst can be obtained first, facilitating its use in treating engine exhaust gases. The active components of the target catalyst include cobalt (Co), chromium (Cr), and indium (In). This target catalyst is designed to enable the co-treatment of CH4 and NO using a single exhaust gas treatment system. X The specific catalyst prepared, as well as the preparation method and process of the target catalyst, will be described in detail in the following examples.

[0033] S102: Place the target catalyst in the co-catalytic reactor.

[0034] S103: Contains methane (CH4) and nitrogen oxides (NO). X The engine exhaust gas is fed into a co-catalytic reactor for exhaust gas treatment.

[0035] In practical applications, a co-catalytic reactor can be installed in the engine exhaust gas treatment system to co-treat CH4 and NO. X This is a complete exhaust gas treatment system. In practical implementation, the target catalyst can be placed in a co-catalytic reactor, thereby treating exhaust gases containing methane (CH4) and nitrogen oxides (NOx). X The engine exhaust gas is fed into a co-catalytic reactor for exhaust gas treatment.

[0036] Understandably, in practical applications, the target catalyst can be placed in the co-catalytic reactor before the engine starts, for example, before the ship begins its voyage. Based on this, after the ship begins its voyage, i.e., after the engine starts, the exhaust gas emitted with the engine can enter the co-catalytic reactor through pipelines for exhaust gas treatment, achieving harmless treatment of the exhaust gas.

[0037] S104: In the exhaust gas treatment process, based on the action of the target catalyst, CH4 is converted into carbon dioxide (CO2) and water (H2O), while NO is converted into CO2. X It is converted into nitrogen gas (N2).

[0038] S105: Co-catalytic reactor for discharging engine exhaust gas after exhaust gas treatment.

[0039] In the exhaust gas treatment process, based on the action of the target catalyst, CH4 can be converted into carbon dioxide (CO2) and water (H2O), while NO can be converted into CO2. X It is converted into nitrogen (N2), thus realizing the synergistic treatment of CH4 and NO by utilizing a co-catalytic reactor as part of the exhaust gas treatment system. X The goal is to simultaneously remove CH4 and NO. X The material transformation equations in the exhaust gas treatment process can be found in the following equation:

[0040]

[0041] In other words, after exhaust gas treatment, both CH4 and NO are removed. X In other words, engine exhaust that has undergone exhaust gas treatment can be considered to meet exhaust emission standards. Specifically, NO in engine exhaust... X Emissions meet IMO Tier III standards, and CH4 emissions meet the second-stage standards of the "Emission Limits and Measurement Methods for Exhaust Pollutants from Marine Engines (China Phase I and II)". Finally, the treated engine exhaust gas can be discharged into the co-catalytic reactor, thus completing the exhaust gas treatment process. This application can utilize only one exhaust gas treatment system, simultaneously co-treating CH4 and NO. XIn this process, CH4 in the exhaust gas is used as a reducing agent to reduce NO. X It is reduced to N2, while CH4 is converted into CO2 and H2O. Compared with the SCR combined with MOC method in related technologies, it does not require an additional reducing agent injection system. Moreover, this application only uses one exhaust gas treatment system, which can simplify the engine exhaust gas treatment system and significantly reduce the cost of LNG engine exhaust gas after-treatment system.

[0042] In the embodiments described above, the target catalyst serves as a synergistic catalyst for the treatment of CH4 and NO. X Specific catalysts are particularly important for exhaust gas treatment. To better understand this, the preparation method and process of the target catalyst will be described in detail below:

[0043] The active components of the target catalyst include cobalt (Co), chromium (Cr), and indium (In), meaning it can be considered a composite catalyst containing multiple active components. In practical applications, the preparation of the target catalyst can be divided into three parts: the first part is the preparation of a first catalyst, whose active components include Cr and In; the second part is the preparation of a second catalyst, whose active component includes Co; and the third part is the preparation of the target catalyst using the first and second catalysts. In practical applications, molecular sieves can be used as supports for preparing the first and second catalysts. In the embodiments of this application, the molecular sieve support used is H-SSZ-13.

[0044] In practical implementation, the molecular sieve support H-SSZ-13 can be obtained first. Then, the first catalyst Cr-In / H-SSZ-13 can be prepared by impregnation with soluble chromium salt, soluble indium salt, and H-SSZ-13. The second catalyst Co / H-SSZ-13 can be prepared by impregnation with soluble cobalt salt and H-SSZ-13. Finally, the target catalyst Co-Cr-In / H-SSZ-13 can be prepared by physical blending equal masses of Cr-In / H-SSZ-13 powder and Co / H-SSZ-13 powder.

[0045] In practical applications, the structure of the molecular sieve support H-SSZ-13 affects its hydrothermal stability and acidity, which in turn affects the catalyst activity. For example, the ratio of silicon to aluminum atoms in H-SSZ-13 has a significant impact on its hydrothermal stability and acidity. For different catalysts, there is an optimal ratio of silicon to aluminum atoms to ensure catalyst activity; it is neither better to be too high nor too low. For the catalyst prepared in this application, experimental verification shows that the optimal value is Si / Al = 10, that is, the ratio of silicon to aluminum atoms in the molecular sieve support H-SSZ-13 is 10.

[0046] Furthermore, the mass percentage of each component in the catalyst can also affect catalyst preparation and catalyst activity. In the embodiments of this application, H-SSZ-13 with Si / Al = 10 is used for catalyst preparation. The specific mass percentages of each component that ensure catalyst preparation and activity are as follows: In Cr-In / H-SSZ-13, the mass percentage of Cr is 1%–4%, the mass percentage of In is 1%–4%, and the mass percentage of H-SSZ-13 is 92%–98%; in Co / H-SSZ-13, the mass percentage of Co is 5%–10%, and the mass percentage of H-SSZ-13 is 90%–95%.

[0047] In the above embodiments, in order to prepare the target catalyst Co-Cr-In / H-SSZ-13, it is necessary to first prepare the first catalyst Cr-In / H-SSZ-13 and the second catalyst Co / H-SSZ-13. The preparation processes of the first catalyst Cr-In / H-SSZ-13 and the second catalyst Co / H-SSZ-13 will be described in detail below.

[0048] (1) The preparation process of the first catalyst Cr-In / H-SSZ-13 is described, specifically including the following steps:

[0049] First, chromium nitrate hydrate (Cr(NO3)3·9H2O), indium nitrate (In(NO3)3), H-SSZ-13, and deionized water (H2O) are added to a preparation container according to a predetermined first mass ratio to obtain a first mixture. The first mass ratio includes a 10% mass ratio of H2O to H-SSZ-13, a 0.01–0.04 mass ratio of In to H-SSZ-13, and a 0.01–0.04 mass ratio of Cr to H-SSZ-13. The preparation container can be a cleaned glass beaker.

[0050] Next, the temperature of the first mixture can be controlled at 25-30°C using a magnetic stirrer, and stirred for 24-48 hours at a speed of 400-500 rpm to allow Cr(NO3)3, In(NO3)3 and H-SSZ-13 to undergo ion exchange, thereby obtaining the first uniform mixed slurry.

[0051] Then, the temperature of the first homogeneous slurry can be controlled at 70-90°C using a magnetic stirrer, and the first homogeneous slurry can be evaporated at a speed of 400-500 rpm, so that the Cr(NO3)3 and (In(NO3)3) in the first homogeneous slurry that have not undergone ion exchange can be loaded onto H-SSZ-13 to obtain the first catalyst to be determined.

[0052] Then, the first undetermined catalyst can be placed in an oven, the temperature of which is controlled at 100-120°C, and dried for 8-16 hours to obtain the dried first undetermined catalyst.

[0053] Finally, the dried first catalyst to be determined can be placed in a heating furnace, the temperature of the heating furnace is controlled at 500℃, and calcined for 2 to 4 hours to obtain the first catalyst Cr-In / H-SSZ-13.

[0054] Based on this, the first catalyst Cr-In / H-SSZ-13 was prepared through impregnation, loading, drying and calcination.

[0055] (2) The preparation process of the second catalyst Co / H-SSZ-13 is described, specifically including the following steps:

[0056] First, cobalt acetate, H-SSZ-13, and deionized water (H2O) can be added to a preparation container according to a set second mass ratio to obtain a second mixture. The second mass ratio includes a mass ratio of H2O to H-SSZ-13 of 10 and a mass ratio of Co to H-SSZ-13 of 0.05 to 0.10. The preparation container can be a cleaned glass beaker.

[0057] Next, the temperature of the second mixture can be controlled at 25-30°C using a magnetic stirrer, and stirred at 400-500 rpm for 24-48 hours to allow cobalt acetate to undergo ion exchange with H-SSZ-13, thereby obtaining a second uniform mixed slurry.

[0058] Then, the temperature of the second homogeneous slurry can be controlled at 70-90°C using a magnetic stirrer, and the second homogeneous slurry can be evaporated at a speed of 400-500 rpm, so that the cobalt acetate in the second homogeneous slurry that has not undergone ion exchange is loaded onto H-SSZ-13 to obtain the second undetermined catalyst.

[0059] Then, the second undetermined catalyst can be placed in an oven, the temperature of which is controlled at 100-120°C, and dried for 12 hours to obtain the dried second undetermined catalyst.

[0060] Finally, the dried second catalyst can be placed in a heating furnace, the temperature of which is controlled at 500℃, and calcined for 2-4 hours to obtain the second catalyst Co / H-SSZ-13.

[0061] Based on this, the second catalyst Co / H-SSZ-13 was prepared through impregnation, loading, drying and calcination.

[0062] (3) The preparation of the target catalyst is described in detail below:

[0063] After preparing Cr-In / H-SSZ-13 and Co / H-SSZ-13, the target catalyst Co-Cr-In / H-SSZ-13 can be prepared by physical blending using the same mass of Cr-In / H-SSZ-13 powder and Co / H-SSZ-13 powder. Based on this, Co-Cr-In / H-SSZ-13 is prepared.

[0064] In practical applications, more uniform target catalyst particles are more advantageous for installation in synergistic catalytic reactors and for tail gas treatment. To achieve more uniform particles, one possible approach is to first prepare the target catalyst by physically blending equal masses of Cr-In / H-SSZ-13 and Co / H-SSZ-13 powders. Then, the target catalyst is pressed into tablets to obtain target catalyst particles. This process converts the powdered target catalyst into granules. Finally, particles meeting a particle diameter threshold are selected as the target catalyst. The particle diameter threshold is used to select target catalyst particles with the required diameter and is typically set based on experimental experience. In practical applications, sieving can be used. Specifically, the target catalyst particles are sieved through a sieve with a mesh size meeting the particle diameter threshold, thus sieving the particles below the threshold to the bottom of the sieve. For example, experimental experience shows that a 40-60 mesh sieve can screen out catalyst particles that meet the requirements. Therefore, the particle diameter threshold can be set to the mesh diameter corresponding to 40-60 mesh. Based on this, the obtained target catalyst particles are more uniform, which facilitates installation in the co-catalytic reactor. At the same time, the gaps between the particles ensure smooth flow of exhaust gas, which is beneficial to improving the exhaust gas treatment effect.

[0065] After obtaining the target catalyst, its effectiveness can be experimentally verified in the laboratory to ensure good exhaust gas treatment performance when applied to engine exhaust. In practical applications, the co-catalytic reactor can include an atmospheric pressure fixed bed. Accordingly, 2.5g of the target catalyst can be placed in the atmospheric pressure fixed bed, and the engine exhaust gas can be a mixture of CH4 (1800ppm), nitric oxide (NO) (600ppm), oxygen (O2) (6%), H2O (10%), and a fixed amount of nitrogen (N2), with N2 serving as the balance gas. The engine exhaust gas can then be introduced into the co-catalytic reactor, with the reaction volume space velocity controlled at 10,000–40,000 h⁻¹. -1 Furthermore, the temperature of the co-catalytic reactor was controlled to rise to 300–530°C for exhaust gas treatment. Based on this, in a laboratory setting, the above-mentioned concentrations of various gases were mixed to simulate engine exhaust gas, and the effectiveness of the target catalyst was verified under corresponding operating parameters (such as the aforementioned reaction volume space velocity and temperature).

[0066] It is understandable that changes in the concentrations of NO and CH4 can reflect the effectiveness of the target catalyst; therefore, the effectiveness of the target catalyst can be evaluated using changes in the concentrations of NO and CH4. In practice, the concentrations of NO and CH4 can be measured using a gas analyzer during the exhaust gas treatment process. This gas analyzer can be a Fourier Transform Infrared Spectrometer (FTIR).

[0067] In the experiment, the catalytic effects of a single first catalyst, a single second catalyst, and the target catalyst were tested, and the NO emission during the exhaust gas treatment process was measured using FTIR. X The concentrations of CH4 and NO were calculated. X The removal efficiency of CH4. Specifically, the first catalyst is 2% Cr-2% In / H-SSZ-13, the second catalyst is 6% Co / H-SSZ-13, and the target catalyst is 6% Co-2% Cr-2% In / H-SSZ-13. Figure 2 The CH4 removal efficiency using the first catalyst, the second catalyst, and the target catalyst is shown. Figure 3 The diagram illustrates NO using a first catalyst, a second catalyst, and a target catalyst. X Removal efficiency. Figure 2 and Figure 3 In the figure, the horizontal axis represents the reaction temperature, which specifically refers to the temperature of the co-catalytic reactor, ranging from 300 to 530°C.

[0068] It should be noted that, for this experiment, in order to obtain a more effective target catalyst, H-SSZ-13 with Si / Al = 10 was selected. That is, among 2%Cr-2%In / H-SSZ-13, 6%Co / H-SSZ-13, and 6%Co-2%Cr-2%In / H-SSZ-13, H-SSZ-13 has Si / Al = 10.

[0069] based on Figure 2 and Figure 3 Experimental results show that 6%Co-2%Cr-2%In / H-SSZ-13 (Si / Al=10) not only maintains the high CH4 removal efficiency of 6%Co / H-SSZ-13 (Si / Al=10), but also achieves higher NO removal efficiency than 2%Cr-2%In / H-SSZ-13 (Si / Al=10). X Removal efficiency. In other words, compared to a single first catalyst or a single second catalyst, the target catalyst prepared based on the first and second catalysts can synergistically remove NO. X It has the same effect as CH4, and can achieve higher NO levels. X Removal efficiency.

[0070] As can be seen from the above technical solution, for engine exhaust gas treatment, the target catalyst can first be obtained. The active components of this target catalyst include cobalt (Co), chromium (Cr), and indium (In), and the target catalyst is placed in a co-catalytic reactor. Then, gases containing CH4 and nitrogen oxides (NOx) can be treated. X The engine exhaust gas is fed into a co-catalytic reactor for exhaust gas treatment. During the treatment process, based on the action of the target catalyst, CH4 can be converted into carbon dioxide (CO2) and water (H2O), while NO is converted into CO2. X It is converted into nitrogen (N2). Finally, the engine exhaust gas, after treatment, can be discharged from the co-catalytic reactor. It can be seen that this is effective for gases containing CH4 and NO. X For engine exhaust gases, a single exhaust gas treatment system consisting of a co-catalytic reactor can be installed, which, under the action of the target catalyst, can simultaneously treat CH4 and NO. X The process is performed to simultaneously remove CH4 and NO. X The purpose is to achieve the following: Compared to the removal methods in related technologies, this application, under the action of the target catalyst, requires only one exhaust gas treatment system to simultaneously remove CH4 and NO. X In other words, it provides a method for co-processing CH4 and NO. X This method simplifies the engine exhaust treatment system and reduces exhaust treatment costs.

[0071] Figure 4This is a structural diagram of an engine exhaust gas treatment device provided in an embodiment of this application. The device includes an acquisition unit 401, a placement unit 402, an inlet unit 403, a conversion unit 404, and an exhaust unit 405.

[0072] The acquisition unit 401 is used to acquire the target catalyst; the active components of the target catalyst include cobalt (Co), chromium (Cr), and indium (In);

[0073] The placement unit 402 is used to place the target catalyst in the co-catalytic reactor;

[0074] The inlet unit 403 is used to introduce a mixture of methane (CH4) and nitrogen oxides (NO). X The engine exhaust gas is fed into the co-catalytic reactor for exhaust gas treatment;

[0075] The conversion unit 404 is used, during the exhaust gas treatment process, to convert CH4 into carbon dioxide (CO2) and water (H2O) based on the action of the target catalyst, and to convert NO... X It is converted into nitrogen gas N2;

[0076] The discharge unit 405 is used to discharge the engine exhaust gas that has undergone exhaust gas treatment from the co-catalytic reactor.

[0077] In one possible implementation, the acquisition unit is further configured to:

[0078] Obtain the molecular sieve support H-SSZ-13;

[0079] The first catalyst Cr-In / H-SSZ-13 was prepared by impregnation using soluble chromium salt, soluble indium salt and H-SSZ-13;

[0080] The second catalyst Co / H-SSZ-13 was prepared by impregnation with soluble cobalt salt and H-SSZ-13.

[0081] The target catalyst Co-Cr-In / H-SSZ-13 was prepared by physical blending using the same mass of Cr-In / H-SSZ-13 powder and Co / H-SSZ-13 powder.

[0082] In one possible implementation, the acquisition unit is further configured to:

[0083] The catalyst to be determined was prepared by physical blending using the same mass of Cr-In / H-SSZ-13 powder and Co / H-SSZ-13 powder.

[0084] The catalyst to be determined is subjected to tableting to obtain catalyst particles;

[0085] Select catalyst particles that meet the particle diameter threshold from the undetermined catalyst particles and use them as the target catalyst.

[0086] In one possible implementation, the particle diameter threshold is the mesh diameter corresponding to 40 to 60 mesh.

[0087] In one possible implementation, the acquisition unit is further configured to:

[0088] Chromium nitrate hydrate Cr(NO3)3·9H2O, indium nitrate (In(NO3)3), the aforementioned H-SSZ-13, and deionized water (H2O) are added to a preparation container according to a set first mass ratio to obtain a first mixture; the first mass ratio includes a mass ratio of H2O to H-SSZ-13 of 10, a mass ratio of In to H-SSZ-13 of 0.01 to 0.04, and a mass ratio of Cr to H-SSZ-13 of 0.01 to 0.04.

[0089] The temperature of the first mixture is controlled at 25-30°C using a magnetic stirrer, and stirred at 400-500 rpm for 24-48 hours to allow ion exchange between the Cr(NO3)3, In(NO3)3 and H-SSZ-13, resulting in a first uniform mixed slurry.

[0090] The temperature of the first homogeneous slurry is controlled at 70-90°C using the magnetic stirrer, and the first homogeneous slurry is evaporated at a speed of 400-500 rpm, so that the Cr(NO3)3 and (In(NO3)3) in the first homogeneous slurry that have not undergone ion exchange are loaded on the H-SSZ-13 to obtain the first undetermined catalyst.

[0091] The first undetermined catalyst was placed in an oven, and the temperature of the oven was controlled at 100-120°C for 8-16 hours to obtain the dried first undetermined catalyst.

[0092] The dried first catalyst to be determined was placed in a heating furnace, and the temperature of the heating furnace was controlled at 500°C for 2-4 hours to obtain the first catalyst Cr-In / H-SSZ-13.

[0093] In one possible implementation, the acquisition unit is further configured to:

[0094] Cobalt acetate, H-SSZ-13, and deionized water (H2O) are added to a preparation container according to a set second mass ratio to obtain a second mixture; the second mass ratio includes a mass ratio of H2O to H-SSZ-13 of 10 and a mass ratio of Co to H-SSZ-13 of 0.05 to 0.10.

[0095] The temperature of the second mixture is controlled at 25-30°C using a magnetic stirrer, and stirred at 400-500 rpm for 24-48 hours to allow the cobalt acetate to undergo ion exchange with the H-SSZ-13, thereby obtaining a second uniform mixed slurry.

[0096] The temperature of the second homogeneous slurry is controlled at 70-90°C using the magnetic stirrer, and the second homogeneous slurry is dried at a speed of 400-500 rpm, so that the cobalt acetate in the second homogeneous slurry that has not undergone ion exchange is loaded on H-SSZ-13 to obtain the second undetermined catalyst.

[0097] The second undetermined catalyst was placed in an oven, and the temperature of the oven was controlled at 100-120°C for 12 hours to obtain the dried second undetermined catalyst.

[0098] The dried second catalyst to be determined was placed in a heating furnace, and the temperature of the heating furnace was controlled at 500°C for calcination for 2-4 hours to obtain the second catalyst Co / H-SSZ-13.

[0099] In one possible implementation, in the Cr-In / H-SSZ-13, the mass percentage of Cr is 1% to 4%, the mass percentage of In is 1% to 4%, and the mass percentage of H-SSZ-13 is 92% to 98%. In the Co / H-SSZ-13, the mass percentage of Co is 5% to 10%, and the mass percentage of H-SSZ-13 is 90% to 95%.

[0100] In one possible implementation, the ratio of silicon atoms to aluminum atoms in the molecular sieve support H-SSZ-13 is 10.

[0101] In one possible implementation, the co-catalytic reactor includes an atmospheric pressure fixed bed, and the placement unit is further configured to:

[0102] The target catalyst, with a mass of 2.5 g, was placed in the atmospheric pressure fixed bed;

[0103] The access unit is also used for:

[0104] The engine exhaust gas is a mixture of CH4 concentration of 1800 ppm, nitric oxide (NO) concentration of 600 ppm, oxygen (O2) concentration of 6%, H2O concentration of 10%, and a fixed amount of nitrogen (N2); the N2 is used as a balance gas.

[0105] The engine exhaust gas is introduced into the co-catalytic reactor, and the reaction volume space velocity of the co-catalytic reactor is controlled to be 10,000–40,000 h⁻¹. -1 The temperature of the co-catalytic reactor is controlled to rise to 300–530°C for tail gas treatment.

[0106] As can be seen from the above technical solution, for engine exhaust gas treatment, the target catalyst can first be obtained. The active components of this target catalyst include cobalt (Co), chromium (Cr), and indium (In), and the target catalyst is placed in a co-catalytic reactor. Then, gases containing CH4 and nitrogen oxides (NOx) can be treated. X The engine exhaust gas is fed into a co-catalytic reactor for exhaust gas treatment. During the treatment process, based on the action of the target catalyst, CH4 can be converted into carbon dioxide (CO2) and water (H2O), while NO is converted into CO2. X It is converted into nitrogen (N2). Finally, the engine exhaust gas, after treatment, can be discharged from the co-catalytic reactor. It can be seen that this is effective for gases containing CH4 and NO. X For engine exhaust gases, a single exhaust gas treatment system consisting of a co-catalytic reactor can be installed, which, under the action of the target catalyst, can simultaneously treat CH4 and NO. X The process is performed to simultaneously remove CH4 and NO. X The purpose is to achieve the following: Compared to the removal methods in related technologies, this application, under the action of the target catalyst, requires only one exhaust gas treatment system to simultaneously remove CH4 and NO. X In other words, it provides a method for co-processing CH4 and NO. X This method simplifies the engine exhaust treatment system and reduces exhaust treatment costs.

[0107] For the device embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to in the description of the method embodiments. The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0108] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0109] The above provides a detailed description of an engine exhaust gas treatment method and apparatus according to embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are merely for the purpose of helping to understand the method of this application. Furthermore, those skilled in the art will recognize that variations in the specific implementation methods and application scope may occur based on the method of this application.

[0110] In summary, the content of this specification should not be construed as limiting this application. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the protection scope of this application. Furthermore, based on the implementation methods provided in the above aspects, this application can be further combined to provide more implementation methods.

Claims

1. A method for treating engine exhaust gas, characterized in that, The method includes: Obtain the target catalyst; the active components of the target catalyst include cobalt (Co), chromium (Cr), and indium (In); The target catalyst is placed in a synergistic catalytic reactor; Will contain methane (CH4) and nitrogen oxides (NO) X The engine exhaust gas is fed into the co-catalytic reactor for exhaust gas treatment; During the exhaust gas treatment process, based on the action of the target catalyst, the CH4 is converted into carbon dioxide (CO2) and water (H2O), and the NO is converted into... X It is converted into nitrogen gas N2; The engine exhaust gas, after completing the exhaust gas treatment, is discharged from the co-catalytic reactor; The acquisition of the target catalyst includes: Molecular sieve support H-SSZ-13 was obtained; the ratio of silicon atoms to aluminum atoms in the molecular sieve support H-SSZ-13 was 10. The first catalyst Cr-In / H-SSZ-13 was prepared by impregnation using soluble chromium salt, soluble indium salt, and H-SSZ-13; in the Cr-In / H-SSZ-13, the mass percentage of Cr is 1%~4%, and the mass percentage of In is 1%~4%. A second catalyst, Co / H-SSZ-13, was prepared by impregnation with a soluble cobalt salt and the aforementioned H-SSZ-13; in the Co / H-SSZ-13, the mass percentage of Co was 5%~10%. The target catalyst Co-Cr-In / H-SSZ-13 was prepared by physical blending of the Cr-In / H-SSZ-13 powder and the Co / H-SSZ-13 powder. In the target catalyst Co-Cr-In / H-SSZ-13, the mass percentage of Co is 6%, the mass percentage of Cr is 2%, and the mass percentage of In is 2%.

2. The method according to claim 1, characterized in that, The preparation of the target catalyst Co-Cr-In / H-SSZ-13 by physically blending equal masses of Cr-In / H-SSZ-13 powder and Co / H-SSZ-13 powder includes: The catalyst to be determined was prepared by physical blending using the same mass of Cr-In / H-SSZ-13 powder and Co / H-SSZ-13 powder. The catalyst to be determined is subjected to tableting to obtain catalyst particles; Select catalyst particles that meet the particle diameter threshold from the undetermined catalyst particles and use them as the target catalyst.

3. The method according to claim 2, characterized in that, The particle diameter threshold is the mesh diameter corresponding to 40~60 mesh.

4. The method according to claim 1, characterized in that, The preparation of the first catalyst Cr-In / H-SSZ-13 by impregnation using soluble chromium salt, soluble indium salt, and H-SSZ-13 includes: Chromium nitrate hydrate Cr(NO3)3·9H2O, indium nitrate (In(NO3)3), the aforementioned H-SSZ-13, and deionized water (H2O) are added to a preparation container according to a set first mass ratio to obtain a first mixture; the first mass ratio includes a mass ratio of H2O to H-SSZ-13 of 10, a mass ratio of In to H-SSZ-13 of 0.01~0.04, and a mass ratio of Cr to H-SSZ-13 of 0.01~0.

04. The temperature of the first mixture is controlled at 25~30℃ using a magnetic stirrer, and stirred at 400~500rpm for 24~48h to allow ion exchange between Cr(NO3)3, In(NO3)3 and H-SSZ-13, resulting in a first uniform mixed slurry. The temperature of the first uniformly mixed slurry is controlled at 70~90℃ using the magnetic stirrer, and the first uniformly mixed slurry is evaporated at a speed of 400~500rpm, so that the Cr(NO3)3 and (In(NO3)3) in the first uniformly mixed slurry that have not undergone ion exchange are loaded on the H-SSZ-13 to obtain the first undetermined catalyst. The first undetermined catalyst was placed in an oven, and the temperature of the oven was controlled at 100~120℃ for 8~16 hours to obtain the dried first undetermined catalyst. The dried first catalyst to be determined was placed in a heating furnace, and the temperature of the heating furnace was controlled at 500℃ for 2~4 hours to obtain the first catalyst Cr-In / H-SSZ-13.

5. The method according to claim 1, characterized in that, The preparation of the second catalyst Co / H-SSZ-13 by impregnation with soluble cobalt salt and H-SSZ-13 includes: Cobalt acetate, H-SSZ-13, and deionized water (H2O) are added to a preparation container according to a set second mass ratio to obtain a second mixture; the second mass ratio includes a mass ratio of H2O to H-SSZ-13 of 10 and a mass ratio of Co to H-SSZ-13 of 0.05 to 0.

10. The temperature of the second mixture is controlled at 25~30℃ using a magnetic stirrer, and stirred at 400~500rpm for 24~48h to allow the cobalt acetate to undergo ion exchange with the H-SSZ-13, thereby obtaining a second uniform mixed slurry. The temperature of the second homogeneous slurry is controlled at 70~90℃ using the magnetic stirrer, and the second homogeneous slurry is dried at a speed of 400~500rpm, so that the cobalt acetate in the second homogeneous slurry that has not undergone ion exchange is loaded on H-SSZ-13 to obtain the second undetermined catalyst. The second undetermined catalyst was placed in an oven, and the temperature of the oven was controlled at 100~120℃ for 12 hours to obtain the dried second undetermined catalyst. The dried second catalyst to be determined was placed in a heating furnace, and the temperature of the heating furnace was controlled at 500℃ for 2~4 hours to obtain the second catalyst Co / H-SSZ-13.

6. The method according to any one of claims 1-5, characterized in that, The co-catalytic reactor includes an atmospheric pressure fixed bed, and placing the target catalyst in the co-catalytic reactor includes: The target catalyst, with a mass of 2.5 g, was placed in the atmospheric pressure fixed bed; The [material] will contain methane (CH4) and nitrogen oxides (NO). X The engine exhaust gas is introduced into the co-catalytic reactor for exhaust gas treatment, including: The engine exhaust gas is a mixture of CH4 concentration of 1800 ppm, nitric oxide (NO) concentration of 600 ppm, oxygen (O2) concentration of 6%, H2O concentration of 10%, and a fixed amount of nitrogen (N2); the N2 is used as a balance gas. The engine exhaust gas is introduced into the co-catalytic reactor, and the reaction volume space velocity of the co-catalytic reactor is controlled to be 10,000~40,000 h⁻¹. -1 The temperature of the co-catalytic reactor is controlled to rise to 300~530℃ for tail gas treatment.

7. An engine exhaust gas treatment device, characterized in that, The device includes an acquisition unit, a placement unit, an inlet unit, a conversion unit, and an outlet unit: The acquisition unit is used to acquire the target catalyst; the active components of the target catalyst include cobalt (Co), chromium (Cr), and indium (In); The placement unit is used to place the target catalyst in the co-catalytic reactor; The inlet unit is used to introduce methane (CH4) and nitrogen oxides (NO). X The engine exhaust gas is fed into the co-catalytic reactor for exhaust gas treatment; The conversion unit is used, during the exhaust gas treatment process, to convert CH4 into carbon dioxide (CO2) and water (H2O) based on the action of the target catalyst, and to convert NO... X It is converted into nitrogen gas N2; The discharge unit is used to discharge the engine exhaust gas that has undergone exhaust gas treatment from the co-catalytic reactor; The acquisition unit is further configured to: Molecular sieve support H-SSZ-13 was obtained; the ratio of silicon atoms to aluminum atoms in the molecular sieve support H-SSZ-13 was 10. The first catalyst Cr-In / H-SSZ-13 was prepared by impregnation using soluble chromium salt, soluble indium salt and H-SSZ-13; In the Cr-In / H-SSZ-13, the mass percentage of Cr is 1%~4%, and the mass percentage of In is 1%~4%. A second catalyst, Co / H-SSZ-13, was prepared by impregnation with a soluble cobalt salt and the aforementioned H-SSZ-13; in the Co / H-SSZ-13, the mass percentage of Co was 5%~10%. The target catalyst Co-Cr-In / H-SSZ-13 was prepared by physical blending of the Cr-In / H-SSZ-13 powder and the Co / H-SSZ-13 powder. In the target catalyst Co-Cr-In / H-SSZ-13, the mass percentage of Co is 6%, the mass percentage of Cr is 2%, and the mass percentage of In is 2%.

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