A catalyst rapid preparation method based on high-frequency alternating magnetic field atmosphere heating

Abstract

This invention discloses a rapid catalyst preparation method based on high-frequency alternating magnetic field atmosphere heating, belonging to the field of rapid catalyst preparation technology, including the following steps: Step 1: Support pretreatment and precursor loading: After surface modification pretreatment of the metal support, the catalyst precursor is uniformly loaded onto the surface of the metal support using precision coating technology; Step 2: Modular coil adaptation: A suitable modular induction coil assembly is selected according to the geometry of the metal support, and the metal support loaded with the precursor is fixed in the central region of the coil. The rapid catalyst preparation method based on high-frequency alternating magnetic field atmosphere heating proposed in this invention achieves spontaneous heating inside the metal support through induction heating, without the need for external furnace contact. This not only avoids the corrosion of equipment by corrosive precursor gases, but also significantly reduces dependence on large high-temperature furnace equipment, shortens the preparation cycle, and improves the safety and economy of the process.

Description

Technical Field

[0001] This invention relates to the field of rapid catalyst preparation technology, specifically a rapid catalyst preparation method based on heating in a high-frequency alternating magnetic field atmosphere. Background Technology

[0002] Catalyst preparation is a key technology in chemical engineering and materials science. It mainly involves combining active components, supports, and auxiliaries through physical, chemical, or biological methods to form functional materials with specific catalytic properties. Its core objective is to control the microstructure of the catalyst to meet the efficiency, selectivity, and stability requirements of different chemical reactions.

[0003] Catalyst preparation often requires high-temperature heating, which currently relies on large furnaces. However, these furnaces have significant limitations. Firstly, large furnaces are expensive and space-consuming, and because they heat the entire furnace chamber, the preparation cycle is long, thermal efficiency is low, and heating response is slow, failing to meet the demands for rapid and efficient preparation. Secondly, during furnace heating, the catalyst precursor easily releases corrosive gaseous components at high temperatures. These gases can cause corrosion and deposits upon contact with the furnace walls or heating elements, reducing equipment lifespan and increasing maintenance frequency and costs. Furthermore, traditional furnace heating typically involves contact heat transfer, resulting in long heat transfer paths and high thermal inertia, making precise temperature control difficult and negatively impacting the uniformity of the catalyst structure and its final performance. Based on these issues, existing catalyst preparation processes face practical technical obstacles in terms of equipment applicability, preparation efficiency, thermal management, and equipment maintenance. Summary of the Invention

[0004] Therefore, the present invention provides a rapid catalyst preparation method based on high-frequency alternating magnetic field atmosphere heating to solve the above-mentioned problems in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a rapid catalyst preparation method based on high-frequency alternating magnetic field atmosphere heating, comprising the following steps: Step 1: Support pretreatment and precursor loading: After surface modification pretreatment of the metal support, the catalyst precursor is uniformly loaded onto the surface of the metal support using precision coating technology; Step 2: Modular coil adaptation: A suitable modular induction coil assembly is selected according to the geometry of the metal support, and the metal support loaded with the precursor is fixed in the central region of the coil; Step 3: Multi-field synergistic heating conversion: A high-frequency alternating magnetic field is generated by a high-frequency heating host to heat the metal support by eddy currents, while an ultrasonic vibration field is introduced to assist the pretreatment process. The catalyst is dispersed to achieve rapid in-situ conversion; Step 4: Intelligent atmosphere and temperature control: Based on the preset process curve, the heating power is adjusted through a closed-loop temperature control system, while the atmosphere gas composition and ratio are dynamically switched by a multi-channel gas control system, and a turbulence device is used to ensure uniform atmosphere distribution; Step 5: In-situ characterization and parameter feedback: During the heating and conversion process, the changes in the catalyst phase structure are analyzed in real time using an in-situ detection device, and the data is fed back to the control system to dynamically optimize the heating parameters; Step 6: Tail gas treatment and energy recovery: The tail gas after the reaction is treated by multiple stages to meet emission standards, and the heat from the tail gas is used to preheat the atmosphere gas entering the reaction system through a waste heat recovery device.

[0006] Further, the detailed operation steps of step one are as follows: The metal support is placed in a plasma cleaner, argon gas is introduced under vacuum conditions, and a working pressure of 10 Pa is maintained at a flow rate of 50 sccm. The plasma is cleaned for 5 min with a radio frequency power of 100 W. Then, the metal support is transferred to a silane coupling agent treatment device, and a 1 wt% γ-APS ethanol solution is sprayed at room temperature for 2 min. After standing for 30 min, it is dried in a 60°C hot air circulating oven for 1 h to form a uniform functionalized layer on the surface. The functionalized metal support is then uniformly loaded with the precursor via an automatic coating platform. The prepared 0.05 mol / L metal salt precursor solution is placed in a precision peristaltic pump supply system and delivered to the nozzle at a flow rate of 10 mL / min. A six-axis spraying robot is used to control the nozzle to maintain a distance of 100 mm from the surface of the metal support. The uniform spraying time is 60 s. After the spraying is completed, the support is sent to an 80°C hot air circulating oven for drying for 30 min to complete the initial fixation and film formation process of the catalyst precursor.

[0007] Furthermore, the detailed operation steps of step two are as follows: Based on the shape and size of the metal carrier, select a matching induction heating coil assembly from the modular coil library to ensure that the size of the coil center area matches the size of the carrier. Then, fix the metal carrier with the precursor already loaded in the center of the coil using a quartz clamp, perform position correction using a laser alignment instrument, and finally lock the clamp and connect the coupling interface between the coil and the high-frequency heating host.

[0008] Furthermore, the detailed operation steps of step three are as follows: turn on the high-frequency heating host, set the frequency output of the induction heating coil to 300kHz and start the resonance mode. The metal carrier is excited by the magnetic field to generate eddy current effect, and the temperature rises rapidly to the set temperature. The heating rate is 50℃ / min. The temperature change is monitored in real time by thermocouple and fed back to the main control unit. At the same time, the ultrasonic auxiliary system is started, the frequency is set to 40kHz, the power is set to 100W, and the heating duration is set to 10min, during which the temperature is kept constant.

[0009] Furthermore, the detailed operation steps of step four are as follows: Before system startup, the preset process temperature curve is loaded into the control module, and the temperature control closed-loop parameters are set to an accuracy of no more than 2℃ above and below. The surface temperature of the metal carrier is collected in real time by a K-type thermocouple and transmitted to the PID controller. The power output of the high-frequency host is adjusted to maintain temperature stability. At the same time, the atmosphere parameters are set to a mixing ratio of 80 vol% nitrogen and 20 vol% hydrogen. The flow rate of each gas is controlled to 100 sccm and 25 sccm respectively by a mass flow controller. After the multi-channel gas mixer completes the ratio adjustment, the gas enters the reaction chamber. The internal turbulence structure is composed of stainless steel annular flow dividers and microporous distribution mesh.

[0010] Furthermore, the detailed operation steps of step five are as follows: an in-situ Raman spectroscopy probe is installed on one side of the reaction chamber, the detection wavelength is set to 532nm, the acquisition frequency is 1Hz, the changes in the surface structure of the catalyst and the characteristic peaks of phase transformation are analyzed in real time, and the data is uploaded to the main control system in conjunction with the optical fiber-connected spectral analysis module. The phase evolution curve is generated in real time on the control interface, and the local temperature distribution map of the carrier is obtained by combining the temperature sensor and the thermal infrared imager.

[0011] Furthermore, the detailed operation steps of step six are as follows: The exhaust gas generated by the reaction first enters the primary coarse filtration device, which is filled with a porous ceramic particle layer with a diameter of 5 mm. After filtering out large particulate impurities, it enters the secondary activated carbon adsorption tower. During the adsorption process, the gas residence time is about 2 seconds. Then, the exhaust gas enters the tertiary condensation device, where the gas is cooled to 25°C through a circulating water cooling system to condense water vapor and condensable components. After the treated exhaust gas is confirmed to meet the emission standards, it is discharged through an exhaust fan at a flow rate of 3 m / s. At the same time, the heat exchanger through which the exhaust gas flows adopts a plate heat exchange structure to recover the heat of the exhaust gas to the inlet gas path, raising the original inlet gas temperature from room temperature of 25°C to a preheating temperature of 80°C.

[0012] Furthermore, the catalyst precursor is a soluble metal salt aqueous solution with a concentration controlled between 0.01 mol / L and 0.1 mol / L. During the spraying process, the movement trajectory of the nozzle adopts a spiral scanning method with a nozzle scanning speed of 50 mm / s to 100 mm / s.

[0013] Furthermore, the induction coil assembly is connected to the circulating cooling system via a pluggable cooling water pipe, wherein the inlet temperature of the cooling water is 20°C and the flow rate is 2L / min.

[0014] Furthermore, a temperature buffer tank is installed between the waste heat recovery device and the inlet gas pipeline. The buffer tank has a hot water jacket structure to achieve a stable temperature transition for gas heat exchange. The gas residence time in the buffer tank is 3 to 5 seconds.

[0015] Compared with existing technologies, it has the following advantages:

[0016] 1. This rapid catalyst preparation method based on high-frequency alternating magnetic field atmosphere heating addresses the problems of high equipment cost, long cycle time, poor safety, and corrosion gas damage to the furnace body caused by the reliance on furnace equipment for high-temperature heating in traditional catalyst preparation. The rapid catalyst preparation method based on high-frequency alternating magnetic field atmosphere heating proposed in this invention achieves spontaneous heating inside the metal carrier through induction heating, without the need for external furnace contact. This not only avoids the corrosion of equipment by corrosive precursor gases, but also significantly reduces the dependence on large high-temperature furnace equipment, shortens the preparation cycle, and improves the safety and economy of the process.

[0017] 2. Plasma cleaning and silane coupling agent functionalization can effectively remove contaminants from the surface of the metal support and introduce functional groups, enhance the interfacial bonding between the precursor and the support, improve the adhesion stability and loading uniformity of the precursor, provide a good foundation for subsequent heating conversion, and improve the consistency and integrity of the final catalyst film formation.

[0018] 3. By combining a six-axis spraying robot with a precision peristaltic pump liquid supply system, the high uniformity of the precursor solution is achieved by controlling the nozzle spiral trajectory and scanning speed. At the same time, a dense precursor film is formed by hot air drying, ensuring the automation, controllability and repeatability of the coating process, improving production consistency and adaptability to large-scale preparation.

[0019] 4. The modular induction heating coil assembly allows for quick replacement of matching coils for metal carriers with different geometries. Combined with a three-dimensional adjustment platform and laser alignment system, it achieves precise coupling between the heating magnetic field and the metal carrier, improving the uniformity of the heat field distribution and avoiding non-uniform heating caused by positional deviations. Attached Figure Description

[0020] To more clearly illustrate the embodiments of the present invention or the technical solutions in 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 merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0021] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0022] Figure 1 This is a flowchart illustrating the steps of a rapid catalyst preparation method based on high-frequency alternating magnetic field atmosphere heating according to the present invention. Detailed Implementation

[0023] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] like Figure 1A rapid catalyst preparation method based on high-frequency alternating magnetic field atmosphere heating includes the following steps: Step 1: Support pretreatment and precursor loading: After surface modification pretreatment of the metal support, the catalyst precursor is uniformly loaded onto the surface of the metal support using precision coating technology; Step 2: Modular coil adaptation: A suitable modular induction coil assembly is selected according to the geometry of the metal support, and the metal support loaded with the precursor is fixed in the central region of the coil; Step 3: Multi-field synergistic heating conversion: A high-frequency alternating magnetic field is generated by a high-frequency heating host to heat the metal support by eddy currents, while an ultrasonic vibration field is introduced to assist in the dispersion of the precursor, thereby realizing catalyst... In-situ rapid conversion; Step 4: Intelligent atmosphere and temperature control: Based on the preset process curve, the heating power is adjusted through a closed-loop temperature control system, while the atmosphere gas composition and ratio are dynamically switched by a multi-channel gas control system, and a turbulence device is used to ensure uniform atmosphere distribution; Step 5: In-situ characterization and parameter feedback: During the heating and conversion process, the changes in the catalyst phase structure are analyzed in real time using an in-situ detection device, and the data is fed back to the control system to dynamically optimize the heating parameters; Step 6: Tail gas treatment and energy recovery: The tail gas after the reaction is treated by multiple stages of purification to meet emission standards, and the heat from the tail gas is used to preheat the atmosphere gas entering the reaction system through a waste heat recovery device.

[0025] The detailed steps of Step 1 are as follows: The metal support is placed in a plasma cleaner, and argon gas is introduced under vacuum conditions. A working pressure of 10 Pa is maintained at a flow rate of 50 sccm. Plasma cleaning with a radio frequency power of 100 W is used for 5 minutes to remove surface impurities and activate the surface. Subsequently, the metal support is transferred to a silane coupling agent treatment device, where a 1 wt% γ-APS ethanol solution is sprayed at room temperature for 2 minutes. After standing for 30 minutes, the solution is dried in a 60°C hot air circulating oven for 1 hour to form a uniform functionalized layer on the surface. The functionalized metal support is then further processed by… A dynamic coating platform is used to uniformly load the precursor. A prepared 0.05 mol / L metal salt precursor solution is placed in a precision peristaltic pump supply system and delivered to the nozzle at a flow rate of 10 mL / min. A six-axis spraying robot controls the nozzle to maintain a distance of 100 mm from the metal carrier surface, and the uniform spraying time is 60 s. After spraying, the carrier is placed in an 80°C hot air circulating oven for drying for 30 min, completing the initial fixation and film formation process of the catalyst precursor. This embodiment further defines the operational details of step one, specifically providing a standardized process for surface modification and precursor loading of the metal carrier. Plasma cleaning technology is used to treat the metal surface in a low-pressure argon environment, which helps remove organic impurities, oxide layers, and particulate contaminants, while activating the metal surface and improving its adhesion to the functional layer. Subsequently, a silane coupling agent containing γ-APS is used to introduce surface functional groups, forming a stable organic-inorganic bridging structure, making the catalyst precursor easier to adhere and distribute uniformly. By leveraging a six-axis spraying robot and a precision liquid supply system, uniform and efficient coating of precursor solutions is achieved. After hot air drying, the precursor is initially film-formed, providing a good foundation for subsequent heating and conversion.

[0026] The detailed steps for step two are as follows: Based on the shape and size of the metal carrier, select a matching induction heating coil assembly from the modular coil library. If the carrier is cylindrical, select a spiral-wound induction coil with an inner diameter 3mm larger than the carrier; if it is a sheet-like structure, select a planar cascaded induction coil. After selection, use a three-dimensional adjustment platform to install the coil inside the induction heating cavity, ensuring that the center area of ​​the coil matches the size of the carrier. Then, fix the metal carrier, which has already been loaded, in the center of the coil using a quartz clamp. Use a laser alignment instrument for position correction, ensuring that the deviation between the center of the metal carrier and the center axis of the coil does not exceed 0.5mm. Finally, tighten the clamp and connect the coupling interface between the coil and the high-frequency heating host. This clarifies the technical process of modular coil selection and carrier fixation in step two. Designing the induction coil structure according to the carrier geometry ensures optimal coupling between the heating magnetic field and the metal carrier, improving heating efficiency and uniformity. A three-dimensional adjustment platform is used to achieve precise matching of the coil's spatial position. Laser alignment technology is then used to ensure the consistency between the coil center and the central axis of the metal carrier, effectively avoiding bias heating and improving the stability of thermal field control, thus laying the foundation for high-efficiency in-situ conversion reactions.

[0027] The detailed operation steps of step three are as follows: Turn on the high-frequency heating host, set the induction heating coil to a frequency output of 300kHz and activate the resonant mode. This generates a high-frequency alternating magnetic field in the coil. The metal carrier is excited by the magnetic field, producing an eddy current effect, rapidly heating to the set temperature, such as 300℃, at a heating rate of 50℃ / min. Temperature changes are monitored in real time via thermocouples and fed back to the main control unit. Simultaneously, the ultrasonic auxiliary system is activated, with the frequency set to 40kHz and the power set to 100W. The ultrasonic transducer transmits vibrations to the bottom of the metal carrier, promoting the dispersion and penetration of the catalyst precursor in the micro-region. The heating duration is set to 10 minutes, during which the temperature remains constant. The synchronous control system coordinates the heating and ultrasonic signals to achieve in-situ conversion under the synergistic effect of multiple fields. The principle of multi-field synergistic heating conversion is explained in detail. The alternating magnetic field generated by the high-frequency induction coil induces eddy currents in the metal carrier, causing internal resistance heating and achieving rapid heating. Simultaneously, an ultrasonic vibration field is introduced, transmitting mechanical waves to the bottom of the carrier through the transducer, generating a micro-disturbance effect, which is beneficial for the nanoscale rearrangement and penetration of the catalyst precursor. This multi-field synergistic mechanism significantly shortens the formation time of the active phase of the catalyst, and improves structural uniformity and reaction selectivity.

[0028] The detailed operation steps of step four are as follows: Before system startup, a preset process temperature curve is loaded into the control module, and the temperature control closed-loop parameters are set to an accuracy of no more than 2℃ above and below. The surface temperature of the metal carrier is collected in real time by a K-type thermocouple and transmitted to the PID controller. The power output of the high-frequency host is adjusted to maintain temperature stability. At the same time, the atmosphere parameters are set to a mixing ratio of 80 vol% nitrogen and 20 vol% hydrogen. The flow rates of each gas are controlled at 100 sccm and 25 sccm respectively by a mass flow controller. After the multi-channel gas mixer completes the proportional adjustment, the gas enters the reaction chamber. The internal turbulence structure consists of a stainless steel annular flow divider and a microporous distribution network to ensure that the gas forms an axial laminar flow in the chamber and avoids dead zone accumulation. The entire atmosphere system is under a positive pressure of 0.1 MPa to prevent external air from seeping in, further defining the composition and control logic of the intelligent atmosphere and temperature control system. By loading the preset temperature curve and the closed-loop PID control strategy, real-time and precise adjustment of the induction heating power is achieved, ensuring that the surface temperature of the metal carrier is stably controlled within the target range. In terms of atmosphere, the mixing ratio of nitrogen and hydrogen is dynamically adjusted by using a mass flow controller and a multi-channel mixer, and the gas flow distribution inside the cavity is optimized by a turbulence structure to form axial laminar flow, avoiding local gas stagnation or uneven mixing, thereby improving the environmental stability of the catalyst reduction reaction.

[0029] The detailed operation steps of step five are as follows: An in-situ Raman spectroscopy probe is installed on one side of the reaction chamber, with the detection wavelength set to 532 nm and the acquisition frequency to 1 Hz. Real-time analysis of catalyst surface structural changes and phase transformation characteristic peaks is performed. Data is uploaded to the main control system via a fiber-optic connected spectral analysis module. Phase evolution curves are generated in real-time on the control interface. Simultaneously, a temperature sensor and thermal infrared imager are used to acquire local temperature distribution maps of the carrier. A data fusion algorithm is used to determine the presence of conversion lag regions or uneven heating regions. If a deviation exceeds a preset threshold, the control system automatically adjusts the coil output power or ultrasonic excitation intensity to ensure the reaction proceeds under optimal conditions. The in-situ Raman spectroscopy probe acquires real-time data on changes in the catalyst surface phase structure, analyzing the formation process and characteristic shift behavior of the active phase. For example, in the reduction of metal oxides, different phases, such as oxidized, sub-oxidized, and metallic states, exhibit significant differences in Raman shifts. These peak position changes can serve as a basis for real-time monitoring. With an acquisition frequency of once per second, the system can respond promptly to changes in activity. Simultaneously, infrared thermal imaging and K-type thermocouples are used to construct a temperature spatial distribution map, and data fusion algorithms are combined to diagnose heating uniformity and reaction progress. Once a region of excessive heat or reaction lag is identified, the system automatically adjusts the induction heating power or ultrasonic field intensity to ensure that the catalyst conversion process is always under optimal thermodynamic conditions, avoiding the formation of heterogeneous structures or underreacted regions. This intelligent closed-loop mechanism of "characterization-feedback-adjustment" not only improves preparation efficiency but also enhances the consistency and controllability of the finished catalyst.

[0030] The detailed operation steps of step six are as follows: The exhaust gas generated by the reaction first enters the primary coarse filtration device, which is filled with a porous ceramic particle layer with a diameter of 5mm. After filtering out large particulate impurities, it enters the secondary activated carbon adsorption tower. During the adsorption process, the gas residence time is about 2 seconds to remove organic components and odor molecules. Then, the exhaust gas enters the tertiary condensation device, where the gas is cooled to 25°C through a circulating water cooling system to condense water vapor and condensable components. After the treated exhaust gas is confirmed to meet the emission standards, it is discharged through the exhaust fan at a flow rate of 3m / s. At the same time, the heat exchanger through which the exhaust gas flows adopts a plate heat exchange structure to recover the heat of the exhaust gas to the inlet gas path, raising the original inlet gas temperature from room temperature of 25°C to a preheating temperature of 80°C, realizing the reuse of waste heat and reducing energy consumption. This refines the exhaust gas treatment and energy recovery scheme of step six, emphasizing its dual purpose of pollution control and energy-efficient utilization. A three-stage exhaust gas treatment system removes impurities step by step: the first stage uses physical filtration, where coarse-porous ceramic particles efficiently trap particulate byproducts precipitated during the reaction; the second stage utilizes the high specific surface area of ​​activated carbon for van der Waals and chemical adsorption of organic components, ensuring the exhaust is odorless and free of volatile pollutants; the third stage condensation device cools the gas through heat exchange, causing water vapor and easily condensable precipitates to be released, preventing corrosion of the downstream exhaust system. The energy recovery section uses a plate heat exchange structure, allowing the high-temperature exhaust gas to exchange heat with the intake path before discharge. A thin-walled metal plate conducts the heat to the low-temperature intake end, preheating the gas to 80°C. This process improves the overall thermal efficiency of the system and significantly reduces additional energy consumption, contributing to long-term stable operation.

[0031] The catalyst precursor is an aqueous solution of a soluble metal salt, with a concentration controlled between 0.01 mol / L and 0.1 mol / L. During spraying, the nozzle's movement trajectory employs a helical scanning method to ensure uniform coating across all areas of the carrier surface. The nozzle scanning speed is 50 mm / s to 100 mm / s, further defining the type of catalyst precursor and spraying process parameters. Soluble metal salt solutions such as aluminum nitrate and copper chloride are used as precursors, allowing for in-situ formation of metal oxides or active metal phases during subsequent heating. Maintaining a concentration between 0.01 mol / L and 0.1 mol / L balances coating uniformity and film quality, preventing insufficient film formation due to excessively low concentration or grain agglomeration due to excessively high concentration. The helical scanning trajectory design of the nozzle, combined with six-axis robot path planning, effectively improves surface coverage uniformity and avoids issues such as thin or recoated edges due to unidirectional movement. The scanning speed is controlled within the range of 50 mm / s to 100 mm / s. This is the result of comprehensive optimization of parameters such as droplet size, spray cone angle, and drying rate, ensuring that the atomized particles are fully deposited without liquid film accumulation.

[0032] The induction coil assembly is connected to a circulating cooling system via a pluggable cooling water pipe. The inlet temperature of the cooling water is 20°C, and the flow rate is 2L / min. This is used to maintain the coil temperature below 50°C to ensure electromagnetic stability and heating uniformity during long-term continuous operation. The cooling structure design of the induction coil system is clearly defined. The induction heating coil generates a large amount of Joule heat during prolonged operation at a 300kHz high-frequency output. If not cooled in time, this will lead to increased copper coil resistance, decreased electromagnetic efficiency, and even coil deformation. Therefore, this invention adopts a pluggable cooling water pipe interface structure for easy replacement and maintenance. Simultaneously, the circulating cooling system continuously supplies 20°C cooling water to keep the coil shell temperature below 50°C, preventing aging or thermal fatigue damage to the cable insulation layer. The 2L / min flow rate setting is based on coil heat transfer load calculations to ensure that the heat flux density is within a safe range. The entire cooling system forms a thermal balance closed loop, which is crucial for heating stability and energy efficiency during continuous operation.

[0033] A temperature buffer tank with a hot water jacket structure is installed between the waste heat recovery unit and the inlet gas pipeline to achieve a stable temperature transition for gas heat exchange. The gas residence time in the buffer tank is 3 to 5 seconds to avoid thermal shock affecting the internal structure of the reactor and the heating system, further enriching the structural details of the tail gas heat recovery system. By introducing a temperature buffer tank into the heat exchange path, the thermal shock problem between the high-temperature tail gas and the low-temperature inlet gas is effectively solved. The hot water jacket structure of the buffer tank can form a gas phase transition zone with a slow temperature rise inside, avoiding material fatigue stress caused by rapid cooling or heating, and extending the service life of the system. The 3 to 5-second residence time of the gas in the buffer tank is designed to provide sufficient heat exchange time while avoiding back pressure or efficiency reduction in the reactor due to excessive gas residence. This structure as a whole improves the stability of the heat exchange process and the safety of the system, which is particularly important for practical industrial applications.

[0034] experiment:

[0035] Example: Rapid preparation and performance analysis of Ni / CeO2 catalysts

[0036] Experimental objective:

[0037] The method of the present invention was verified to achieve efficient in-situ conversion of metal precursors within 10 minutes and to obtain Ni / CeO2 supported catalyst with excellent dispersibility and structural uniformity.

[0038] Experimental materials and equipment

[0039] Metal carrier: a cylindrical 316L stainless steel sheet with a diameter of 20mm and a thickness of 2mm.

[0040] Precursor solution: 0.05 mol / L Ni(NO3)2·6H2O and 0.01 mol / L Ce(NO3)3 dissolved in ethanol-water (volume ratio 7:3).

[0041] Cleaning equipment: Radio frequency plasma cleaner.

[0042] Coating equipment: a six-axis spraying robot + a peristaltic pump liquid supply system.

[0043] Induction heating system: high-frequency induction heating host, adjustable power 1.5kW.

[0044] Coil structure: Helical modular induction coil.

[0045] Ultrasonic field system: 40kHz frequency, 100W transducer.

[0046] Atmosphere control system: Nitrogen + Hydrogen mass flow controller.

[0047] In-situ detection system: 532nm Raman probe + spectrometer.

[0048] Thermocouples and infrared imagers.

[0049] Exhaust gas treatment system: ceramic filter + activated carbon adsorption + condensation heat exchange system

[0050] Heat exchange preheating device + buffer tank

[0051] Experimental steps:

[0052] Step 1: Carrier pretreatment and precursor loading

[0053] The metal carrier was placed in the plasma cleaning chamber, the argon flow rate was 50 sccm, the vacuum was set to 10 Pa, and the cleaning was carried out for 5 minutes to remove surface oxides.

[0054] Surface functionalization treatment: Spray with 1 wt% γ-APS (γ-aminopropyltriethoxysilane) ethanol solution for 2 minutes, let stand for 30 minutes and then dry at 60℃ for 1 hour;

[0055] Precursor solution for spraying: delivered at a rate of 10 mL / min by a precision peristaltic pump, with a six-axis nozzle 100 mm away from the carrier, a scanning speed of 80 mm / s, and a spiral trajectory spraying for 60 s;

[0056] After spraying, it is placed in an 80℃ hot air oven to dry for 30 minutes.

[0057] Step 2: Modular Coil Adaptation

[0058] Select a spiral induction coil with an inner diameter of 23mm and install it in the three-dimensional adjustment platform;

[0059] After the coating has dried, the carrier is fixed in a quartz fixture and placed in the center of the coil. The alignment is achieved by laser, and the deviation is adjusted to not exceed 0.5 mm.

[0060] Step 3: Multi-field synergistic heating conversion

[0061] Start the high-frequency heating unit, set the frequency to 300kHz, and the heating rate to 50℃ / min;

[0062] The ultrasonic transducer (40kHz, 100W) is started synchronously to couple the vibration to the bottom of the carrier;

[0063] Heat to 300℃ and maintain the temperature for 10 minutes;

[0064] The thermocouple provides real-time temperature feedback to the PID module, ensuring that fluctuations do not exceed ±1℃.

[0065] Step 4: Intelligent Atmosphere and Temperature Control

[0066] The atmosphere was set to 80% nitrogen and 20% hydrogen, with flow rates of 100 sccm and 25 sccm, respectively.

[0067] A uniform axial airflow is formed by a gas mixer and a baffle plate, and a positive pressure of 0.1 MPa is maintained inside the cavity;

[0068] The control module loads a preset temperature curve and adjusts the heating output in a closed loop.

[0069] Step 5: In-situ characterization and parameter feedback

[0070] The Raman system (λ = 532 nm, sampling frequency 1 Hz) was activated to record Ni during the catalyst conversion process online. 2 +→Ni 0 Peak position migration and Ce phase changes;

[0071] The thermal imager records the temperature distribution on the surface of the carrier and uses the thermocouple feedback system to determine the heating uniformity.

[0072] If an abnormal area is detected (e.g., a temperature difference greater than ±5℃), the system will automatically adjust the heating power or ultrasonic intensity.

[0073] Step Six: Exhaust Gas Treatment and Energy Recovery

[0074] The reaction tail gas first passes through a porous ceramic particle filter layer, and then enters the activated carbon adsorption tower and condensation unit.

[0075] Discharged after passing emission tests and meeting emission standards;

[0076] The exhaust gas is preheated by a plate heat exchanger, raising the nitrogen temperature from 25°C to 80°C. The gas remains in the buffer tank for about 4 seconds to ensure the slow release of thermal shock.

[0077] Experimental Results and Analysis:

[0078] XRD analysis showed that Ni in the converted catalyst sample 0 The characteristic peaks are clear, the CeO2 crystal planes are not damaged, and the grain size is approximately 8 nm.

[0079] TEM characterization showed that the Ni particles were evenly distributed without obvious agglomeration, and the carrier and active components were tightly bound together.

[0080] In-situ Raman data showed that the conversion reaction showed a metallic Ni signal at 6 minutes and tended to stabilize after 9 minutes. The conversion time was much shorter than that of the traditional calcination route (which usually takes 2-4 hours).

[0081] Energy efficiency comparison results show that, under the same final catalytic performance, this method reduces energy consumption by about 68% and has no pollution emissions.

[0082] Experimental conclusion:

[0083] This experiment fully verifies the high efficiency, environmental friendliness, and structural control capabilities of the method described in this invention. Through the synergistic effect of high-frequency magnetic induction heating and ultrasonic fields, precursor reduction and transformation can be achieved in a short time. Combined with atmosphere control and an in-situ feedback system, a highly controllable rapid catalyst preparation pathway can be constructed, suitable for the industrial continuous preparation of various supported catalysts.

[0084] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

[0085] The terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity of description and are not intended to limit the scope of the invention. Any changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

Claims

1. A method for rapid preparation of a catalyst based on heating in an atmosphere of high-frequency alternating magnetic field, characterized in that, The method comprises the following steps: Step 1: carrier pretreatment and precursor loading: after surface modification pretreatment of the metal carrier, the catalyst precursor is uniformly loaded on the surface of the metal carrier by precise coating technology; Step 2: modular coil adaptation: according to the geometric shape of the metal carrier, an appropriate modular induction coil assembly is selected, and the metal carrier loaded with the precursor is fixed in the central area of the coil; Step 3: multi-field synergistic heating conversion: a high-frequency alternating magnetic field is generated by a high-frequency heating host to cause eddy current heating of the metal carrier, while an ultrasonic vibration field is introduced to assist the dispersion of the precursor, realizing in-situ rapid conversion of the catalyst; Step 4: intelligent atmosphere and temperature regulation: based on the preset process curve, the heating power is adjusted by a closed-loop temperature control system, while the atmosphere gas composition and ratio are dynamically switched by a multi-channel gas control system, and the atmosphere is uniformly distributed by a spoiler device; Step 5: in-situ characterization and parameter feedback: during the heating and conversion process, the in-situ detection device is used to analyze the phase structure change of the catalyst in real time, and the data is fed back to the control system to dynamically optimize the heating parameters; Step 6: tail gas treatment and energy recovery: the tail gas after reaction is treated by multi-stage purification to meet the emission standard, and the heat of the tail gas is used to preheat the atmosphere gas entering the reaction system through a waste heat recovery device, The detailed operation steps of step 1 are as follows: the metal carrier is placed in a plasma cleaning machine, argon gas is introduced under vacuum conditions, the working pressure is maintained at 10 Pa with a flow rate of 50 sccm, and the plasma is cleaned for 5 min with a radio frequency power of 100 W. Then the metal carrier is transferred to a silane coupling agent treatment device, an ethanol solution of 1 wt% γ-APS is sprayed at room temperature, the spraying time is controlled for 2 min, and after standing for 30 min, it is dried in a hot air circulation oven at 60°C for 1 h to form a uniform functional layer on the surface. The functionalized metal carrier is then uniformly loaded with the precursor by an automatic coating platform. The prepared 0.05 mol / L metal salt precursor solution is placed in a precision peristaltic pump liquid supply system, and delivered to the spray head at a flow rate of 10 mL / min. The six-axis spraying robot controls the distance between the spray head and the metal carrier surface to be 100 mm, and the uniform spraying time is 60 s. After spraying, the carrier is sent to a hot air circulation oven at 80°C for 30 min to complete the preliminary fixation and film formation of the catalyst precursor; The detailed operation steps of step 3 are as follows: start the high-frequency heating host, set the induction heating coil to a frequency output of 300 kHz and start the resonance mode, the metal carrier is excited by the magnetic field to generate eddy current effect, and the temperature is quickly raised to the set temperature at a rate of 50 ℃ / min. The temperature change is monitored in real time by a thermocouple and fed back to the main control unit, and at the same time the ultrasonic auxiliary system is started, the frequency is set to 40 kHz, the power is set to 100 W, and the heating duration is set to 10 min, during which the temperature remains constant. The detailed operation steps of the step five are as follows: an in-situ Raman spectrum probe is installed on one side of the reaction cavity, the detection wavelength is set to 532 nm, the acquisition frequency is 1 Hz, the real-time analysis of the catalyst surface structure change and the phase conversion characteristic peak is performed, the data is uploaded to the main control system through the spectrum analysis module connected by the optical fiber, the phase evolution curve is generated in real time on the control interface, and the local temperature distribution map of the carrier is obtained by combining the temperature sensor and the thermal infrared imager.

2. The method for rapid preparation of a catalyst based on heating in an atmosphere of high-frequency alternating magnetic field according to claim 1, characterized in that, The detailed operation steps of the step two are as follows: according to the shape and size of the metal carrier, a matching induction heating coil assembly is selected from the modular coil library to ensure that the coil center region matches the size of the carrier, then the metal carrier on which the precursor has been loaded is fixed in the middle of the coil through a quartz clamp, position correction is performed by using a laser alignment instrument, finally the clamp is locked and the coupling interface of the coil and the high-frequency heating host is connected.

3. The catalyst rapid preparation method based on high-frequency alternating magnetic field atmosphere heating according to claim 1, characterized in that, The detailed operation steps of the step four are as follows: before the system starts, a preset process temperature curve is loaded to the control module, the temperature control closed loop parameters are set to an accuracy of not more than 2 ℃ up and down, the surface temperature of the metal carrier is collected in real time by a K-type thermocouple and transmitted to a PID controller, the power output of the high-frequency host is adjusted to maintain the temperature stable, the atmosphere parameters are set to a mixed ratio of 80 vol% nitrogen and 20 vol% hydrogen, the flow rates of each gas are controlled to be 100 sccm and 25 sccm respectively by mass flow controllers, and after the ratio adjustment is completed by a multi-channel gas mixer, the mixed gas enters the reaction cavity, and the internal turbulence structure is composed of a stainless steel annular shunt and a microporous distribution net.

4. The catalyst rapid preparation method based on high-frequency alternating magnetic field atmosphere heating according to claim 1, characterized in that, The detailed operation steps of the step six are as follows: the tail gas generated in the reaction first enters a primary rough filter device filled with a layer of porous ceramic particles with a diameter of 5 mm, then enters a secondary activated carbon adsorption tower, and the gas residence time in the adsorption process is 2 s, then the tail gas enters a tertiary condensing device, and the gas is cooled to 25 ℃ by a circulating water cooling system to condense water vapor and condensable components, after the treated tail gas is detected to meet the emission standard, it is discharged by an exhaust fan at a flow rate of 3 m / s, and at the same time, the heat exchanger through which the tail gas flows adopts a plate heat exchange structure to recover the heat of the tail gas to the inlet gas path, so that the original inlet gas is raised from room temperature 25 ℃ to preheating temperature 80 ℃.

5. The catalyst rapid preparation method based on high-frequency alternating magnetic field atmosphere heating according to claim 1, characterized in that, The moving track of the spray head in the spraying process adopts a spiral scanning mode, and the scanning speed of the spray head is 50 mm / s to 100 mm / s.

6. The method for rapid preparation of a catalyst based on heating in an atmosphere of high-frequency alternating magnetic field according to claim 1, characterized in that, The induction coil assembly is connected with the circulating cooling system through a plug-in type cooling water pipe, the inlet temperature of the cooling water is 20 ℃, and the flow rate is 2 L / min.

7. The method for rapid preparation of a catalyst based on heating in an atmosphere of high-frequency alternating magnetic field according to claim 1, characterized in that, A temperature buffer tank is arranged between the waste heat recovery device and the inlet gas pipeline, the buffer tank has a hot water jacket structure for realizing temperature stable transition of gas heat exchange, and the gas residence time in the buffer tank is 3 s to 5 s.

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