Vehicle-mounted methanol reforming hydrogen production catalyst, preparation method and application thereof

Abstract

The application belongs to the technical field of hydrogen energy catalytic materials, and specifically discloses a vehicle-mounted methanol reforming hydrogen production catalyst as well as a preparation method and application thereof, which comprises a porous metal honeycomb carrier, an anti-vibration adhesive layer, a nitrogen-doped mesoporous alumina carrier and PdZnGa ternary alloy nanoparticles arranged in sequence; the anti-vibration adhesive layer is coated on the surface of the porous metal honeycomb carrier, the anti-vibration adhesive layer is formed by mixing aluminum sol and silicon sol, and the coating thickness is 50-100 microns; the nitrogen-doped mesoporous alumina carrier is loaded on the anti-vibration adhesive layer, and the surface of the nitrogen-doped mesoporous alumina carrier is anchored with PdZnGa ternary alloy nanoparticles. The vehicle-mounted methanol reforming hydrogen production catalyst, the preparation method and the application thereof are adopted to improve the low-temperature activity, stability and anti-vibration performance of the catalyst from the material level, and adapt to the requirements of vehicle-mounted miniaturization and dynamic working conditions.

Description

Technical Field

[0001] This invention relates to the field of hydrogen energy catalytic materials technology, and in particular to an on-board methanol reforming hydrogen production catalyst, its preparation method, and its application. Background Technology

[0002] Vehicles can directly produce hydrogen on their own platforms. By integrating miniaturized hydrogen production devices into mobile platforms, hydrogen-producing feedstocks (such as water, ammonia, methanol, and organic liquid hydrogen storage carriers) are converted into hydrogen for direct use in fuel cells or hydrogen internal combustion engines. This represents an important development direction in the field of hydrogen energy transportation. Among these technologies, on-board methanol reforming for hydrogen production has become a key area of ​​development for hydrogen fuel cell vehicles due to its advantages, such as not requiring hydrogen refueling stations and the ease of storing and transporting feedstocks.

[0003] In existing technologies, PdZn / Al2O3 catalysts are widely used in on-board methanol reforming for hydrogen production. Pd and Zn form a PdZn alloy, whose electronic structure becomes similar to that of metallic copper (Cu), thereby reducing the selectivity for CO and increasing the selectivity for CO2. However, a methanol conversion rate of over 99% is required at 280-320℃. Under long-term high-temperature operation, the interaction between Al2O3 and the metal is limited, and high temperatures easily lead to the aggregation and growth of PdZn alloy particles, reducing active sites and shortening catalyst life. In addition, without anti-vibration design, the coating is prone to peeling off under vehicle vibration, resulting in poor stability and making it difficult to achieve the industrial-grade lifespan of ≤5% attenuation after 10,000 hours. Summary of the Invention

[0004] The purpose of this invention is to provide an on-board methanol reforming hydrogen production catalyst, its preparation method and application, which improves the low-temperature activity, stability and shock resistance of the catalyst from the material level, and is suitable for the needs of vehicle miniaturization and dynamic operating conditions.

[0005] To achieve the above objectives, the present invention provides an on-board methanol reforming hydrogen production catalyst, comprising a porous metal honeycomb support, a shock-resistant bonding layer, a nitrogen-doped mesoporous alumina support, and PdZnGa ternary alloy nanoparticles arranged sequentially. The anti-seismic bonding layer is coated on the surface of the porous metal honeycomb carrier. The anti-seismic bonding layer is made of a mixture of aluminum sol and silica sol, and the coating thickness is 50~100μm. The nitrogen-doped mesoporous alumina carrier is loaded on the anti-vibration bonding layer, and PdZnGa ternary alloy nanoparticles are anchored on the surface of the nitrogen-doped mesoporous alumina carrier. The surface of the PdZnGa ternary alloy nanoparticles is coated with a silicon dioxide protective layer.

[0006] Preferably, the mass ratio of aluminum sol to silica sol is 3~5:1.

[0007] Preferably, the molar ratio of Pd, Zn, and Ga in the PdZnGa ternary alloy nanoparticles is 1:2~4:0.1~0.5, the average particle size of the PdZnGa ternary alloy nanoparticles is 2~5 nm, and the particle size distribution deviation is ≤10%.

[0008] Preferably, the nitrogen doping amount in the nitrogen-doped mesoporous alumina carrier is 2~5 at%, of which the pyridine nitrogen content accounts for 60~80% of the total nitrogen content, thereby constructing surface acid-base defect sites and confined pores.

[0009] Preferably, the thickness of the silicon dioxide protective layer is 1~3nm and the pore size is 0.5~1nm.

[0010] This invention provides a method for preparing an on-board methanol reforming hydrogen production catalyst, comprising the following steps: S1. Carrier pretreatment: The porous metal honeycomb carrier is subjected to acid washing, alkali washing and plasma treatment to improve surface roughness; S2, anti-seismic bonding layer coating: aluminum sol, silica sol and deionized water are mixed to obtain a slurry. The pretreated porous metal honeycomb carrier is immersed in the slurry, taken out, dried and calcined to obtain intermediate 1. S3. Preparation of nitrogen-doped mesoporous alumina support: Aluminum nitrate, urea and citric acid are dissolved in deionized water, stirred and evaporated to obtain a gel. The gel is dried and calcined to obtain nitrogen-doped mesoporous alumina powder. S4, PdZnGa ternary alloy nanoparticle support: The nitrogen-doped mesoporous alumina powder obtained in S3 was dispersed in deionized water, palladium nitrate, zinc nitrate and gallium nitrate solutions were added, stirred, sodium borohydride was added as a reducing agent to react, filtered, washed, dried and then reduced under hydrogen atmosphere to obtain PdZnGa / Al2O3 catalyst powder. S5, Silica protective layer coating: A silica protective layer was deposited on the surface of the PdZnGa / Al2O3 catalyst powder obtained in S4 by atomic layer deposition to obtain intermediate 2; S6. Catalyst coating preparation: Intermediate 2 obtained in S5, deionized water, and binder are mixed and coated on the surface of the anti-vibration bonding layer of intermediate 1 obtained in S2. After drying and calcination, the on-board methanol reforming hydrogen production catalyst is obtained.

[0011] In S3, aluminum nitrate, urea, and citric acid are mixed in a mass ratio of 10:3~5:1~2; the drying temperature is 100~150℃, the drying time is 10~14h; the calcination temperature is 600~700℃, and the calcination time is 4~6h.

[0012] In step S4, the mass ratio of the nitrogen-doped mesoporous alumina powder to the sodium borohydride is 2:1, the reducing agent reaction time is 2-3 hours, and after filtration, washing, and drying, it is reduced for 2-3 hours at a hydrogen flow rate of 50-100 mL / min.

[0013] In S5, the atomic layer deposition method is specifically as follows: Tetraethoxysilane and deionized water were mixed to obtain the precursor. The deposition temperature was 150°C and the deposition cycle was 20-30 times.

[0014] This invention provides an application of an on-board methanol reforming hydrogen production catalyst in an on-board fuel cell methanol reforming hydrogen production system.

[0015] Preferred application methods include: T1. Cold start low temperature temperature rise control stage: After the vehicle is powered on, the combined gradient temperature rise of the reforming reactor is achieved by using the waste heat exhaust gas of the fuel cell and the electric auxiliary heat at a rate of 2~5℃ / min. The temperature is maintained until the catalyst is activated and the concentration of hydrogen-rich CO is stable to within the threshold, thus completing the low temperature activation start-up. T2, Steady-state reforming constant temperature precision control stage: Under steady-state conditions of vehicle cruising and uniform speed driving, the reactor bed temperature is stably locked at 220~280℃ through waste heat staged recovery closed-loop regulation; the bed temperature, methanol feed flow rate, and water-methanol ratio are collected in real time, and the heat exchange medium flow rate and electric auxiliary heating power are dynamically fine-tuned to control the bed temperature fluctuation ≤3℃, not exceeding the 320℃ high temperature boundary, and maintaining high conversion rate, low CO, and low carbon deposition steady-state operation; T3, Dynamic Temperature Adjustment Stage: When the vehicle accelerates, decelerates, climbs, or idles, the bed temperature is adjusted at a rate of 1~3℃ / min to limit sudden temperature rises and falls; when the load is increased, the temperature is raised to 250~280℃ to increase the hydrogen production rate, and when the load is reduced, the temperature is lowered to 220~240℃ to reduce side reactions and carbon deposits.

[0016] Preferably, when the ambient temperature is -30~0℃, the feed liquid is first preheated to 50~70℃, and then the bed temperature is gradually increased. A coupled control model of temperature, space velocity, and water-to-alcohol ratio is established. During the cold start-up low-temperature temperature rise control stage, the water-to-alcohol ratio is 1.3~1.5 and the space velocity is 6000~8000 h⁻¹. -1 During the steady-state reforming isothermal precise control stage, the water-to-alcohol ratio is 1.1~1.3, and the space velocity is 8000~12000 h⁻¹. -1 During the dynamic temperature control phase, the water-to-alcohol ratio in the temperature-raising section is 1.2~1.4, and the space velocity is 7000~10000 h⁻¹. -1 .

[0017] Therefore, the present invention employs the above-mentioned on-board methanol reforming hydrogen production catalyst, its preparation method, and its application, and the beneficial effects are as follows: The triple modification of the catalyst synergistically broadens the operating temperature window, enabling stable activation at 180℃ and maintaining good anti-sintering performance at 320℃; The segmented temperature control operation strategy is adapted to the characteristics of the catalyst to achieve high conversion rate, low CO selectivity and low carbon deposition rate under all operating conditions. The anti-vibration bonding layer and silica confinement design meet the long-term use requirements of vehicle vibration + temperature alternation coupled environment.

[0018] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the vehicle-mounted methanol reforming hydrogen production catalyst of Embodiment 1 of the present invention; Figure 2 This is a graph showing the changes in primary methanol conversion rate and CO selectivity with temperature for Example 1 and Comparative Example 1 of the present invention, where (A) is the change in primary methanol conversion rate with temperature and (B) is the change in CO selectivity with temperature. Figure 3 The graph shows the 10,000-hour stability test results of Example 1 and Comparative Example 1 of the present invention, where (A) is the change of methanol conversion rate with temperature and (B) is the change of CO selectivity with temperature. Figure 4 This is a graph showing the results of 100 heating and cooling cycles of Embodiment 1 and Comparative Example 1 of the present invention.

[0020] Figure Labels 1. Porous metal honeycomb carrier; 2. Shock-resistant bonding layer; 3. Nitrogen-doped mesoporous alumina carrier; 4. PdZnGa ternary alloy nanoparticles; 5. Silica protective layer. Detailed Implementation

[0021] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0022] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0023] Example 1 An on-board methanol reforming hydrogen production catalyst, with the following structure: Figure 1 As shown, from the inside out, the structure consists of: 1. a porous metal honeycomb carrier made of 300-mesh stainless steel; 2. a 70μm thick aluminosilicate sol anti-vibration bonding layer; 3. a nitrogen-doped mesoporous alumina carrier; 4. PdZnGa ternary alloy nanoparticles with a Pd:Zn:Ga molar ratio of 1:3:0.2; and 5. a 2nm thick silicon dioxide protective layer.

[0024] Its preparation method is as follows: Carrier pretreatment: The stainless steel honeycomb carrier was immersed in 10% dilute nitric acid for 30 minutes and rinsed with deionized water until neutral; then immersed in 5% sodium hydroxide solution for 15 minutes and rinsed with deionized water until neutral; finally, it was subjected to plasma treatment for 10 minutes under argon atmosphere with a power of 100W.

[0025] Applying an anti-seismic transition bonding layer: Mix aluminum sol and silica sol at a mass ratio of 4:1, adjust the viscosity to 100 mPa·s, immerse the pretreated carrier in the slurry, remove and blow off the excess slurry, dry at 120℃ for 2 hours, and calcine at 500℃ for 2 hours.

[0026] Preparation of nitrogen-doped mesoporous alumina: 10g aluminum nitrate, 4g urea and 1.5g citric acid were dissolved in 100mL deionized water, evaporated at 80℃ to form a gel, dried at 120℃ for 12 hours and calcined at 650℃ for 5 hours to obtain nitrogen-doped mesoporous alumina powder.

[0027] Supported ternary alloy: 1g of the above support was dispersed in 50mL of deionized water, and palladium nitrate, zinc nitrate and gallium nitrate solutions were added to make the molar ratio of Pd:Zn:Ga 1:3:0.2. 0.5g of sodium borohydride was added and reacted at room temperature for 2 hours. After filtration and washing, the mixture was dried at 120℃ for 12 hours and reduced at 380℃ and 70mL / min hydrogen flow rate for 2.5 hours.

[0028] Deposition of a silica protective layer: Atomic layer deposition was used with tetraethoxysilane and water as precursors, and 20 cycles were performed at 150°C to obtain a 2 nm thick silica protective layer.

[0029] Preparation of finished product: The catalyst powder is made into a slurry, coated on a honeycomb carrier with an adhesive layer, dried at 120°C for 2 hours, and calcined at 450°C for 3 hours.

[0030] Its applications are as follows: T1. Cold start low temperature temperature rise control stage: After the vehicle is powered on, the combined gradient temperature rise of the reforming reactor is achieved by using the waste heat exhaust gas of the fuel cell and the electric auxiliary heat at a rate of 2~5℃ / min. The temperature is maintained until the catalyst is activated and the concentration of hydrogen-rich CO is stable to within the threshold, thus completing the low temperature activation start-up. T2, Steady-state reforming constant temperature precision control stage: Under steady-state conditions of vehicle cruising and uniform speed driving, the reactor bed temperature is stably locked at 220~280℃ through waste heat staged recovery closed-loop regulation; the bed temperature, methanol feed flow rate, and water-methanol ratio are collected in real time, and the heat exchange medium flow rate and electric auxiliary heating power are dynamically fine-tuned to control the bed temperature fluctuation ≤3℃, not exceeding the 320℃ high temperature boundary, and maintaining high conversion rate, low CO, and low carbon deposition steady-state operation; T3, Dynamic Temperature Adjustment Stage: When the vehicle accelerates, decelerates, climbs, or idles, the bed temperature is adjusted at a rate of 1~3℃ / min to limit sudden temperature rises and falls; when the load is increased, the temperature is raised to 250~280℃ to increase the hydrogen production rate, and when the load is reduced, the temperature is lowered to 220~240℃ to reduce side reactions and carbon deposits.

[0031] When the ambient temperature is -30~0℃, the feed liquid is first preheated to 50~70℃, and then the bed temperature is gradually increased. A coupled control model of temperature, space velocity, and water-to-alcohol ratio is established. During the cold start-up and low-temperature temperature rise control stage, the water-to-alcohol ratio is 1.3~1.5 and the space velocity is 6000~8000 h⁻¹. -1 During the steady-state reforming isothermal precise control stage, the water-to-alcohol ratio is 1.1~1.3, and the space velocity is 8000~12000 h⁻¹. -1 During the dynamic temperature control phase, the water-to-alcohol ratio in the temperature-raising section is 1.2~1.4, and the space velocity is 7000~10000 h⁻¹. -1 .

[0032] Example 2 The difference from Example 1 is that the thickness of the mesoporous silica confined protective layer is 2.5 nm, and the number of atomic layer deposition cycles is 25.

[0033] Example 3 The difference from Example 1 is that the thickness of the mesoporous silica confined protective layer is 3 nm, and the atomic layer deposition cycle is 30.

[0034] Comparative Example 1 A traditional PdZn / Al2O3 catalyst is prepared as follows: Carrier pretreatment: Immerse the stainless steel honeycomb carrier in 10% dilute nitric acid for 30 minutes, and rinse with deionized water until neutral.

[0035] Directly coated catalyst: Commercial γ-Al2O3 powder was mixed with palladium nitrate and zinc nitrate solution to prepare a slurry with a Pd:Zn molar ratio of 1:3. The slurry was directly coated onto the pretreated metal honeycomb carrier, dried at 120°C for 2 hours, and calcined at 450°C for 3 hours.

[0036] Test 1. Catalyst activity and selectivity testing: A fixed-bed microreactor was used for testing, with a catalyst loading volume of 1 mL, a reaction pressure of 0.2 MPa, a water-to-ethanol ratio of 1.2, and a space velocity of 10000 h⁻¹. -1 CO was detected using a thermal conductivity detector (TCD), and methanol was detected using a flame ionization detector (FID).

[0037] Depend on Figure 2It can be seen that the catalyst of Example 1 has a methanol conversion rate of 91.2% at 180℃, 99.1% at 220℃, 99.5% at 280℃, and 97.3% at 320℃; the CO selectivity is ≤0.45% across the entire temperature range. The catalyst of Comparative Example 1 has a methanol conversion rate of 65.3% at 180℃, 78.5% at 220℃, 92.1% at 280℃, and 82.7% at 320℃; the CO selectivity is ≥2.1% across the entire temperature range.

[0038] 2. Stability test: Continuous operation for 10,000 hours in a fixed-bed reactor under the following conditions: temperature 250℃, pressure 0.2MPa, water-to-ethanol ratio 1.2, and space velocity 10,000 h⁻¹. -1 Methanol conversion rate and CO selectivity were analyzed every 200 hours, and the activity decay rate was calculated.

[0039] Depend on Figure 3 It can be seen that after 10,000 hours of continuous operation in Example 1, the methanol conversion rate was 94.5%, the activity decreased by 4.7%, and the CO selectivity was 0.52%, with no significant increase. After 10,000 hours of continuous operation in Comparative Example 1, the methanol conversion rate was 66.1%, the activity decreased by 28.3%, and the CO selectivity increased to 4.5%, with severe carbon buildup.

[0040] 3. Simulate temperature fluctuations under vehicle operating conditions, perform 100 heating and cooling cycles between 180 and 320°C, with a heating and cooling rate of 2°C / min, and maintain a constant temperature at each temperature point for 1 hour to test the change in catalyst activity before and after the cycle.

[0041] Depend on Figure 4 It can be seen that after 100 heating and cooling cycles, Example 1 showed a methanol conversion rate of 98.7%, an activity decrease of 0.4%, and no obvious carbon deposition. Comparative Example 1 showed a methanol conversion rate of 80.5%, an activity decrease of 12.6%, and obvious particle agglomeration. It is evident that traditional catalysts have drawbacks such as poor low-temperature activity, high CO selectivity, poor stability, and weak shock resistance, failing to meet the long-term stable operation requirements of on-board methanol reforming hydrogen production systems.

[0042] 4. Seismic test: Conducted according to GB / T 28046.3-2011 standard, vibration frequency 10~2000Hz, acceleration 10g, vibration time 1000 hours, mass change of catalyst coating before and after test, and coating peeling rate calculated.

[0043] After 1000 hours of vibration, the coating peeling rate of Example 1 was 0.08%, that of Example 2 was 0.07%, and that of Example 3 was 0.05%, all far below the industry standard requirement of ≤1%. This indicates that increasing the thickness of the silica protective layer further improves the high-temperature stability and anti-sintering performance of the catalyst, making it more suitable for heavy-duty truck on-board reforming systems operating under high loads and for extended periods.

[0044] Therefore, the present invention adopts the above-mentioned vehicle-mounted methanol reforming hydrogen production catalyst, its preparation method and application, which improves the low-temperature activity, stability and shock resistance of the catalyst from the material level, and is suitable for vehicle-mounted miniaturization and dynamic operating conditions.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A vehicle-mounted methanol reforming hydrogen production catalyst, characterized in that: It includes a porous metal honeycomb carrier, a shock-resistant bonding layer, a nitrogen-doped mesoporous alumina carrier, and PdZnGa ternary alloy nanoparticles arranged in sequence. The anti-seismic bonding layer is coated on the surface of the porous metal honeycomb carrier. The anti-seismic bonding layer is made of a mixture of aluminum sol and silica sol, and the coating thickness is 50~100μm. The nitrogen-doped mesoporous alumina carrier is loaded on the anti-vibration bonding layer, and PdZnGa ternary alloy nanoparticles are anchored on the surface of the nitrogen-doped mesoporous alumina carrier. The surface of the PdZnGa ternary alloy nanoparticles is coated with a silicon dioxide protective layer.

2. The on-board methanol reforming hydrogen production catalyst according to claim 1, characterized in that: The mass ratio of aluminum sol to silica sol is 3~5:

1.

3. The on-board methanol reforming hydrogen production catalyst, its preparation method, and its application according to claim 1, characterized in that: The molar ratio of Pd, Zn, and Ga in PdZnGa ternary alloy nanoparticles is 1:2~4:0.1~0.5, and the average particle size of PdZnGa ternary alloy nanoparticles is 2~5 nm with a particle size distribution deviation ≤10%.

4. The on-board methanol reforming hydrogen production catalyst according to claim 1, characterized in that: The nitrogen doping content in the nitrogen-doped mesoporous alumina carrier is 2~5 at%, of which pyridine nitrogen content accounts for 60~80% of the total nitrogen content.

5. The on-board methanol reforming hydrogen production catalyst according to claim 1, characterized in that: The thickness of the silicon dioxide protective layer is 1~3nm and the pore size is 0.5~1nm.

6. A method for preparing an on-board methanol reforming hydrogen production catalyst as described in any one of claims 1 to 5, characterized in that, Includes the following steps: S1. Carrier pretreatment: The porous metal honeycomb carrier is subjected to acid washing, alkali washing and plasma treatment; S2, anti-seismic bonding layer coating: aluminum sol, silica sol and deionized water are mixed to obtain a slurry. The pretreated porous metal honeycomb carrier is immersed in the slurry, taken out, dried and calcined to obtain intermediate 1. S3. Preparation of nitrogen-doped mesoporous alumina support: Aluminum nitrate, urea and citric acid are dissolved in deionized water, stirred and evaporated to obtain a gel. The gel is dried and calcined to obtain nitrogen-doped mesoporous alumina powder. S4, PdZnGa ternary alloy nanoparticle support: The nitrogen-doped mesoporous alumina powder obtained in S3 was dispersed in deionized water, palladium nitrate, zinc nitrate and gallium nitrate solutions were added, stirred, sodium borohydride was added as a reducing agent to react, filtered, washed, dried and then reduced under hydrogen atmosphere to obtain PdZnGa / Al2O3 catalyst powder. S5, Silica protective layer coating: A silica protective layer was deposited on the surface of the PdZnGa / Al2O3 catalyst powder obtained in S4 by atomic layer deposition to obtain intermediate 2; S6. Catalyst coating preparation: Intermediate 2 obtained in S5, deionized water, and binder are mixed and coated on the surface of the anti-vibration bonding layer of intermediate 1 obtained in S2. After drying and calcination, the on-board methanol reforming hydrogen production catalyst is obtained.

7. The method for preparing an on-board methanol reforming hydrogen production catalyst according to claim 6, characterized in that, In S3, aluminum nitrate, urea, and citric acid are mixed in a mass ratio of 10:3~5:1~2; the drying temperature is 100~150℃, the drying time is 10~14h; the calcination temperature is 600~700℃, and the calcination time is 4~6h.

8. The method for preparing an on-board methanol reforming hydrogen production catalyst according to claim 6, characterized in that, In step S4, the mass ratio of the nitrogen-doped mesoporous alumina powder to the sodium borohydride is 2:1, the reducing agent reaction time is 2-3 hours, and after filtration, washing, and drying, it is reduced for 2-3 hours at a hydrogen flow rate of 50-100 mL / min.

9. The application of an on-board methanol reforming hydrogen production catalyst as described in any one of claims 1 to 5, or an on-board methanol reforming hydrogen production catalyst prepared by the preparation method described in any one of claims 6 to 8, in an on-board fuel cell methanol reforming hydrogen production system.

10. The application according to claim 9, characterized in that, Application methods include: T1. Cold start low temperature rise control stage: After the vehicle is powered on, the combined gradient temperature rise of the reforming reactor is achieved by using the waste heat exhaust gas of the fuel cell and electric auxiliary heating at a rate of 2~5℃ / min, raising the temperature of the reforming reactor from room temperature to 180~220℃. T2, Steady-state reforming constant temperature precision control stage: Under steady-state conditions of vehicle cruising and uniform speed driving, the reactor bed temperature is stably locked at 220~280℃ through waste heat staged recovery closed-loop regulation; real-time acquisition of bed temperature at multiple points, methanol feed flow rate, water-methanol ratio, dynamic fine adjustment of heat exchange medium flow rate and electric auxiliary heating power, control bed temperature fluctuation ≤3℃, maintain high conversion rate, low CO, low carbon deposition steady-state operation; T3, Dynamic Temperature Adjustment Stage under Changing Operating Conditions: When the vehicle accelerates, decelerates, climbs hills, or idles, the bed temperature is adjusted at a rate of 1~3℃ / min; when the load increases, the temperature is raised to 250~280℃, and when the load decreases, the temperature is lowered to 220~240℃.

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