A gradient temperature and pressure reaction kettle for preparing a furfural composite catalyst and a control method thereof

Abstract

The application discloses a gradient temperature and pressure reaction kettle for preparing a furfural composite catalyst and a control method thereof, and relates to the technical field of reaction kettles. The gradient temperature and pressure reaction kettle for preparing the furfural composite catalyst comprises a reaction kettle body provided with a feeding pipe and a discharging pipe, and further comprises a vertical pipe rotatably installed in the reaction kettle body, wherein an outer wall of the vertical pipe is provided with a horizontal frame, a plurality of longitudinally arranged stirring rods are installed on the horizontal frame, and an inner heat exchange assembly is arranged in the vertical pipe; a plurality of circumferentially distributed protruding portions are arranged at equal intervals on an inner wall of the reaction kettle body, wherein the two sides of the protruding portions and the inner wall of the reaction kettle body are connected through inclined surfaces; through the arrangement of the cavity and the heat exchange cavity, the raw materials in and outside the reaction kettle body can be heated at the same time, so that the raw materials are heated more uniformly, and the final quality and efficiency of the catalyst are also significantly improved.

Description

Technical Field

[0001] This invention relates to the field of reaction vessel technology, specifically to a gradient temperature and pressure swing reactor for the preparation of furfural composite catalysts and its control method. Background Technology

[0002] The preparation of composite catalysts for furfural is essentially a complex solid-liquid phase reaction sequence involving multi-component precursor co-precipitation, crystallization, ion exchange, and high-temperature reduction. These steps need to be carried out sequentially under strictly sealed, controlled atmosphere (such as nitrogen or hydrogen) and precise temperature and pressure conditions. Therefore, a high-pressure reactor must be used as the core carrier to ensure that the reaction environment is closed and oxygen-free, with sufficient mass transfer and the ability to safely execute multi-stage heating programs. This allows for the control of the nucleation and growth of active metals at the atomic scale, ultimately obtaining a finished catalyst with an ideal crystal structure, high specific surface area, and uniform distribution of active sites.

[0003] However, existing conventional reactors exhibit a significant drawback in practical use: their heating method primarily relies on electric heating elements embedded in the reactor wall or jacket. Heat must be conducted from the outside in through the metal wall to the bulk material, causing the raw materials near the inner wall of the reactor to heat up rapidly and participate in the reaction first. Meanwhile, the materials near the central axis region experience a significant temperature lag due to the long heat conduction path and high thermal resistance. Although mechanical or magnetic stirring devices are installed inside the reactor to force convection and enhance heat transfer, in high-viscosity slurry systems or large-volume reactors, stirring cannot completely eliminate the radial temperature gradient. This inherent axial and radial temperature difference not only prolongs the waiting time to reach the preset reaction temperature but also causes catalyst precursors in different spatial locations within the reactor to experience different thermal histories, leading to problems such as uneven grain size, premature agglomeration of active components, or collapse of the support structure. Ultimately, this severely reduces the overall activity, selectivity, and batch-to-batch consistency of furfural hydrogenation catalysts, hindering further improvements in production efficiency and product quality. Summary of the Invention

[0004] This invention provides a gradient temperature and pressure swing reactor for the preparation of furfural composite catalysts. By setting up a cavity and a heat exchange cavity, the raw materials inside and outside the reactor body can be heated simultaneously, thereby making the raw materials more uniformly heated and significantly improving the final quality and efficiency of the catalyst. This solves the problem of uneven heating inside and outside mentioned in the background art, which restricts production efficiency and product quality.

[0005] This invention provides the following technical solution: A gradient temperature and pressure swing reactor for preparing furfural composite catalysts includes a reactor body with an inlet pipe and an outlet pipe, and further includes: a vertical pipe rotatably installed inside the reactor body; wherein a horizontal frame is installed on the outer wall of the vertical pipe, and a plurality of longitudinally arranged stirring rods are installed on the horizontal frame, and an internal heat exchange assembly is provided inside the vertical pipe; a plurality of circumferentially distributed protrusions are equally spaced on the inner wall of the reactor body; wherein the two sides of the protrusions are connected to the inner wall of the reactor body by inclined transitions, and an external heat exchange assembly is provided inside the inner wall of the reactor body.

[0006] As a preferred embodiment of the present invention, the internal heat exchange assembly includes an end cap rotatably connected to the upper end of the vertical pipe, an inner pipe extending into the vertical pipe is fixedly installed on the end cap, a heat exchange cavity is formed between the outer wall of the inner pipe and the inner wall of the vertical pipe, and an output pipe is fixedly connected to the upper end of the end cap.

[0007] As a preferred embodiment of the present invention, the external heat exchange assembly includes a cavity formed inside the reactor body. The cavity is shaped like a plum blossom due to the protrusion. An inlet pipe and an outlet pipe are fixedly connected to the upper and lower outer walls of the reactor body, respectively. Both the inlet pipe and the outlet pipe are connected to the cavity.

[0008] As a preferred embodiment of the present invention, the outer wall of the vertical tube is provided with a slot, the horizontal frame is slidably installed in the slot, a limiting plate is provided inside the vertical tube and fixedly connected to the end of the horizontal frame, a spring is installed between the limiting plate and the inner wall of the vertical tube, and the horizontal frame is pushed against the inner wall of the reactor body under the elastic force of the spring.

[0009] As a preferred embodiment of the present invention, a rotating tube is rotatably mounted at the end of the crossbeam and fits against the inner wall of the reactor body, and a spiral blade is fixedly mounted on the inner wall of the rotating tube.

[0010] As a preferred embodiment of the present invention, a downwardly bent pipe is rotatably mounted on the top of the rotating pipe, and the bent pipe is fixedly connected to the cross frame through a connecting frame.

[0011] As a preferred embodiment of the present invention, the axial cross-section of the stirring rod is rectangular, and the stirring rod is inclinedly arranged on the cross frame, with an inclined flow channel formed between two adjacent stirring rods, so that multiple stirring rods are distributed on the cross frame in an inverted V-shape.

[0012] As a preferred embodiment of the present invention, supports are fixedly connected to both sides of the crossbar, and a crossbar is rotatably mounted on each of the two supports via a rotating shaft. A scraper is fixedly connected to the end of the crossbar, and a torsion spring is installed between the rotating shaft and the support. The elastic force of the torsion spring causes the scraper to adhere to the outer wall of the vertical tube.

[0013] As a preferred embodiment of the present invention, a drive motor is fixedly installed on the reactor body, and a transmission gear is fixedly installed on both the output shaft of the drive motor and the outer wall of the vertical tube, and the two transmission gears are meshed together.

[0014] A method for controlling a gradient temperature-pressure swing reactor for the preparation of furfural composite catalysts includes the following steps: S1: Loading and airtightness check The composite catalyst precursor and solvent are added to the reactor body, sealed, and nitrogen is introduced for multiple purgings to remove the air from the reactor body. Then, nitrogen or hydrogen at a certain pressure is introduced to perform an airtightness test to confirm that the system has no leaks. S2: Gradient heating stage The controller heats the reactor body in segments according to a preset temperature-time gradient curve. The gradient heating is not a linear, continuous heating, but rather a step-by-step progressive heating mode. First stage (low temperature activation): Set temperature T1, heating rate r1, hold temperature for t1 after reaching target value to promote the initial decomposition of catalyst precursor. Second stage (intermediate temperature crystallization): Heat to T2 at a rate r2, and hold at a constant temperature t2; The third stage (high temperature reduction / calcination): Under an inert or reducing atmosphere, the temperature is increased to T3 at a rate of r3 and held at a constant temperature of t3 to complete the final shaping of the catalyst. S3: Transformer Co-control Within each isothermal range of the gradient heating, the controller synchronously performs pressure transformation operations; the pressure setpoint is dynamically adjusted according to the temperature range, specifically through the following strategy: In the low-temperature range, a low pressure P1 is maintained to facilitate the removal of solvents or template agents from the precursor. After entering the medium-high temperature section, based on the rate of thermal expansion of the gas inside the reactor and the rate of gas consumption by the chemical reaction, the pressure is increased to P2 or P3 in stages by adjusting the opening of the inlet valve and the outlet valve. S4: Cooling and pressure relief After the reaction is completed, the program controls the cooling water to enter the jacket and coil for cooling. At the same time, the pressure is gradually released according to the set rate. After the temperature drops to a safe range and the pressure returns to zero, the discharge pipe at the bottom of the reactor body is opened to remove the material.

[0015] Compared with the prior art, the present invention provides a gradient temperature and pressure swing reactor for the preparation of furfural composite catalysts, which has the following advantages: 1. In the gradient temperature and pressure change reactor used for the preparation of furfural composite catalyst, the raw materials inside and outside the reactor body can be heated simultaneously through the setting of the cavity and heat exchange cavity, thereby making the raw materials more uniformly heated and significantly improving the final quality and efficiency of the catalyst. The setting of the protrusion will significantly increase the inner surface area of ​​the reactor body, thereby enabling the external heat exchange components to heat the raw materials more efficiently and uniformly.

[0016] 2. In the gradient temperature and pressure change reactor used for the preparation of furfural composite catalyst, when the horizontal frame is continuously rotated by the vertical pipe, the end of the horizontal frame will always be attached to the inner wall of the reactor body under the action of the spring. Thus, the protrusion and the inclined surface will cause the horizontal frame to move back and forth in the slot, which will in turn drive the stirring rod to move back and forth. This can significantly improve the stirring effect of the stirring rod on the raw materials, make the raw materials heat more evenly, and improve the reaction effect.

[0017] 3. In the gradient temperature and pressure change reactor used for the preparation of furfural composite catalyst, the rotating tube is driven by the cross frame to roll along the inner wall of the reactor body. The rotating tube will continuously roll and press the inner wall of the reactor body, making it less likely for agglomeration to occur inside.

[0018] 4. In the gradient temperature and pressure change reactor used for the preparation of furfural composite catalyst, the raw materials in the reactor body will flow towards the middle of the crossbeam along the inclined flow channel through the set flow channel. This will prevent some raw materials from staying near the inner wall of the reactor body and the outer wall of the vertical pipe for a long time. With the crossbeam and stirring rod moving back and forth, the raw materials can be heated and mixed more evenly.

[0019] 5. In the gradient temperature and pressure swing reactor used for the preparation of furfural composite catalyst, the scraper moves synchronously back and forth via the horizontal frame. When the scraper approaches the vertical tube, the scrapers on both sides of the horizontal frame gradually increase their angle. When it moves away from the vertical tube, the torsion spring causes the two scrapers to gradually decrease their angle. The scraper always adheres to the outer wall of the vertical tube, thus removing the raw material accumulated on the outer wall of the vertical tube. In addition, the scraper also drives the horizontal bar to swing back and forth, which, together with the stirring rod, can further improve the stirring effect of the raw material.

[0020] The parts of this device not covered are the same as or can be implemented using existing technologies. Through the arrangement of the cavity and heat exchange cavity, the raw materials inside and outside the reactor body can be heated simultaneously, thereby making the raw materials more uniformly heated and significantly improving the final quality and efficiency of the catalyst. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, the elements or parts are not necessarily drawn to actual scale.

[0022] Figure 1 This is a three-dimensional illustration of the present invention. Figure 1 ; Figure 2 This is a three-dimensional illustration of the present invention. Figure 2 ; Figure 3 This is a top-view sectional view of the present invention. Figure 1 ; Figure 4 This is a top-view cross-sectional view of another working state of the present invention; Figure 5 For the present invention Figure 3 Schematic diagram of a local structure in the middle; Figure 6 This is a three-dimensional schematic diagram of a partial structure of the present invention. Figure 1 ; Figure 7 This is a partial cross-sectional view of the structure of the present invention; Figure 8 This is a three-dimensional schematic diagram of a partial structure of the present invention. Figure 2 .

[0023] In the diagram: 1. Reactor body; 2. Feed pipe; 3. Discharge pipe; 4. Vertical pipe; 5. Protrusion; 6. Cavity; 7. Liquid inlet pipe; 8. Liquid outlet pipe; 9. Horizontal frame; 10. Stirring rod; 11. Drive motor; 12. Transmission gear; 13. End cover; 14. Inner pipe; 15. Output pipe; 16. Limiting plate; 17. Spring; 18. Rotary pipe; 19. Spiral blade; 20. Bend; 21. Connecting frame; 22. Support; 23. Rotating shaft; 24. Horizontal bar; 25. Scraper; 26. Branch rod; 27. Inclined surface; 28. Flow channel; 29. ​​Heat exchange chamber; 30. Groove. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0025] Example: Reference Figures 1-8As shown, a gradient temperature and pressure swing reactor for the preparation of furfural composite catalysts includes a reactor body 1 with an inlet pipe 2 and an outlet pipe 3. Valves are installed on both the inlet pipe 2 and the outlet pipe 3. The reactor body 1 is also equipped with a pressure sensor, a temperature sensor, and a pressure pipe for adjusting the pressure inside the reactor body 1. The reactor body 1 also includes a vertical pipe 4, rotatably installed inside the reactor body 1, with the axis of the vertical pipe 4 collinear with the axis of the reactor body 1. A horizontal frame 9 is installed on the outer wall of the vertical pipe 4. Multiple longitudinally arranged stirring rods 10 are installed, and an internal heat exchange component is provided inside the vertical tube 4; multiple circumferentially distributed protrusions 5 are equally spaced on the inner wall of the reactor body 1; wherein, the two sides of the protrusions 5 are connected to the inner wall of the reactor body 1 by inclined surfaces 27, and an external heat exchange component is provided inside the inner wall of the reactor body 1; a drive motor 11 is fixedly installed on the reactor body 1, and a transmission gear 12 is fixedly installed on both the output shaft of the drive motor 11 and the outer wall of the vertical tube 4, and the two transmission gears 12 are meshed together.

[0026] Specifically, during use, the raw materials are added to the reactor body 1 through the feed pipe 2, and then the vertical pipe 4 is heated through the heat exchange component, and the inner wall of the reactor body 1 is heated through the external heat exchange component. Thus, the raw materials inside and outside the reactor body 1 can be heated simultaneously, making the raw materials more uniformly heated, and the final quality and efficiency of the catalyst will be significantly improved. During this period, the drive motor 11 drives the vertical pipe 4 to rotate through two meshing transmission gears 12, and the vertical pipe 4 drives the stirring rod 10 through the cross frame 9 to complete the stirring of the raw materials, making the raw materials more uniformly mixed and heated. The protrusion 5 significantly increases the inner surface area of ​​the reactor body 1, thereby enabling the external heat exchange component to heat the raw materials more efficiently and uniformly.

[0027] Of course, in other implementations, refer to Figures 1-7 As shown, the above-mentioned internal heat exchange assembly includes an end cap 13 rotatably connected to the upper port of the vertical pipe 4. An inner pipe 14 extending into the vertical pipe 4 is fixedly installed on the end cap 13. A heat exchange cavity 29 is formed between the outer wall of the inner pipe 14 and the inner wall of the vertical pipe 4. An output pipe 15 is fixedly connected to the upper end of the end cap 13.

[0028] Specifically, during use, steam is delivered into the inner tube 14, where it flows downwards and enters the bottom of the vertical tube 4. It then flows upwards along the heat exchange chamber 29 and is finally discharged from the output pipe 15. When the steam flows through the heat exchange chamber 29, it heats the vertical tube 4, which in turn heats the raw materials inside the reactor body 1 through its outer wall. In addition, when it is necessary to cool the raw materials inside the reactor body 1, coolant is delivered into the inner tube 14.

[0029] Of course, in other implementations, refer to Figures 1-4 As shown, the external heat exchange assembly includes a cavity 6 opened in the reactor body 1. The cavity 6 is shaped like a plum blossom under the action of the protrusion 5. The upper and lower outer walls of the reactor body 1 are respectively fixedly connected to an inlet pipe 7 and an outlet pipe 8. Both the inlet pipe 7 and the outlet pipe 8 are connected to the cavity 6.

[0030] Specifically, during use, steam is delivered into cavity 6 through inlet pipe 7, then flows to the bottom of cavity 6, and finally exits from outlet pipe 8. When steam flows through cavity 6, it heats the inner wall of reactor body 1, which in turn heats the raw materials inside. In addition, when it is necessary to cool the raw materials inside reactor body 1, coolant is delivered into inlet pipe 7.

[0031] Reference Figures 4-8 As shown, the outer wall of the vertical tube 4 is provided with a slot 30, and the horizontal frame 9 is slidably installed in the slot 30. The vertical tube 4 is provided with a limiting plate 16 that is fixedly connected to the end of the horizontal frame 9. A spring 17 is installed between the limiting plate 16 and the inner wall of the vertical tube 4. The horizontal frame 9 is pushed against the inner wall of the reactor body 1 by the elastic force of the spring 17.

[0032] Specifically, when the vertical tube 4 drives the horizontal frame 9 to rotate continuously, the end of the horizontal frame 9 will always be attached to the inner wall of the reactor body 1 under the action of the spring 17. As a result, the protrusion 5 and the inclined surface 27 will cause the horizontal frame 9 to move back and forth in the slot 30, which will in turn drive the stirring rod 10 to move back and forth. This can significantly improve the stirring effect of the stirring rod 10 on the raw materials, making the raw materials heat more evenly and the reaction effect better.

[0033] Reference Figures 4-8 As shown, a rotating tube 18 is rotatably mounted on the end of the cross frame 9 and attached to the inner wall of the reactor body 1. A spiral blade 19 is fixedly mounted on the inner wall of the rotating tube 18. A downwardly bent tube 20 is rotatably mounted on the top of the rotating tube 18. The bent tube 20 is fixedly connected to the cross frame 9 through a connecting frame 21.

[0034] Specifically, as the horizontal frame 9 rotates along with the vertical tube 4, the horizontal frame 9 drives the rotating tube 18 to roll along the inner wall of the reactor body 1. The rotating tube 18 continuously rolls against the inner wall of the reactor body 1, making it less prone to agglomeration and accumulation. It also draws the raw material from the bottom of the reactor body 1 through the internal spiral blades 19 and then transports it to the top bend tube 20. Finally, it is discharged from the bend tube 20 back into the reactor body 1. This prevents the raw material from settling at the bottom of the reactor body 1. Combined with the reciprocating stirring rod 10 and the horizontal frame 9, the uniformity of the raw material can be significantly improved.

[0035] Reference Figures 3-5As shown, the axial cross-section of the stirring rod 10 is rectangular, and the stirring rod 10 is inclinedly arranged on the cross frame 9. An inclined flow channel 28 is formed between two adjacent stirring rods 10, so that multiple stirring rods 10 are distributed on the cross frame 9 in an inverted V-shape.

[0036] Specifically, during the continuous stirring of the stirring rod 10, the raw materials in the reactor body 1 will flow along the inclined flow channel 28 towards the middle of the crossbar 9, which means that the raw materials will flow away from the inner wall of the pressure reactor body 1 and the outer wall of the vertical pipe 4. As a result, some raw materials will not stay near the inner wall of the reactor body 1 and the outer wall of the vertical pipe 4 for a long time. With the crossbar 9 and stirring rod 10 moving back and forth, the raw materials can be heated and mixed more evenly.

[0037] Reference Figures 3-8 As shown, supports 22 are fixedly connected to both sides of the crossbar 9. A crossbar 24 is rotatably mounted on each of the two supports 22 via a pivot 23. A scraper 25 is fixedly connected to the end of the crossbar 24. A torsion spring is installed between the pivot 23 and the support 22. The elastic force of the torsion spring causes the scraper 25 to adhere to the outer wall of the vertical tube 4.

[0038] Specifically, when the horizontal frame 9 moves back and forth, it will also drive the scraper 25 to move back and forth synchronously. When the scraper 25 moves closer to the vertical pipe 4, the scraper 25 on both sides of the horizontal frame 9 will gradually increase the angle. When it moves away from the vertical pipe 4, the torsion spring will cause the two scraper 25 to gradually decrease the angle. The scraper 25 will always be in contact with the outer wall of the vertical pipe 4, so the raw material accumulated on the outer wall of the vertical pipe 4 can be scraped off. In addition, the scraper 25 will also drive the horizontal bar 24 to swing back and forth. In conjunction with the stirring rod 10, the mixing effect of the raw material can be further improved.

[0039] Reference Figure 5 As shown, multiple equally spaced branch rods 26 are fixedly connected to the aforementioned limiting plate 16. When the crossbeam 9 moves back and forth horizontally, it will also drive the branch rods 26 to move back and forth horizontally inside the vertical pipe 4. The branch rods 26 will stir the steam inside the vertical pipe 4, thereby enabling the steam to heat the vertical pipe 4 more efficiently.

[0040] Reference Figures 1-8 A method for controlling a gradient temperature-pressure swing reactor for the preparation of furfural composite catalysts includes the following steps: S1: Loading and airtightness check The composite catalyst precursor and solvent are added to the reactor body 1, sealed, and nitrogen is introduced for multiple purgings to remove the air from the reactor body 1. Then, nitrogen or hydrogen at a certain pressure is introduced to perform an airtightness test to confirm that the system has no leaks.

[0041] S2: Gradient heating stage The controller heats the reactor body 1 in segments according to a preset temperature-time gradient curve. The gradient heating is not a linear, continuous heating, but rather a step-by-step progressive heating mode. First stage (low temperature activation): Set temperature T1 (e.g., 80℃-120℃), heating rate r1, and hold at constant temperature for t1 after reaching the target value to promote the initial decomposition of the catalyst precursor.

[0042] The second stage (medium-temperature crystallization): the temperature is increased to T2 (e.g., 150℃-180℃) at a rate r2 and then kept constant at t2. In this stage, the controller adopts a cascade PID control algorithm, with the material temperature as the main variable and the jacket temperature as the secondary variable, to suppress temperature overshoot and ensure that the temperature control accuracy is within ±0.5℃.

[0043] The third stage (high-temperature reduction / calcination): Under an inert or reducing atmosphere, the temperature is increased to T3 (e.g., 200℃-250℃) at a rate r3, and held at a constant temperature t3 to complete the final shaping of the catalyst.

[0044] S3: Transformer Co-control Within each isothermal range of the gradient heating process, the controller synchronously performs pressure transformation. The pressure setpoint is dynamically adjusted according to changes in the temperature range, specifically through the following strategy: In the low-temperature range, a low pressure P1 (e.g., 1.0-1.5 MPa) is maintained to facilitate the removal of solvents or template agents from the precursor.

[0045] After entering the medium-high temperature section, based on the rate of thermal expansion of the gas inside the reactor body 1 and the rate of gas consumption by the chemical reaction, the pressure is increased in stages to P2 (e.g., 2.0-3.0 MPa) or P3 (e.g., 4.0-5.0 MPa) by adjusting the opening of the inlet valve and the outlet valve to meet the hydrogen partial pressure requirements of the reduction reaction.

[0046] During pressure regulation, the control algorithm automatically corrects the pressure setpoint based on the slope of temperature change, avoiding large pressure fluctuations caused by temperature lag.

[0047] S4: Cooling and pressure relief After the reaction is completed, the program controls the cooling water to enter the jacket and coil for cooling. At the same time, the pressure is gradually released according to the set rate. After the temperature drops to a safe range (e.g., <50℃) and the pressure returns to zero, the discharge pipe 3 at the bottom of the reactor body 1 is opened to take out the material.

[0048] Components not described in detail in this article are existing technologies.

[0049] 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 the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A gradient temperature and pressure swing reactor for preparing furfural composite catalysts, comprising a reactor body (1) equipped with a feed pipe (2) and a discharge pipe (3), characterized in that, Also includes: The vertical pipe (4) is rotatably installed inside the reactor body (1); The vertical tube (4) is equipped with a horizontal frame (9) on its outer wall, and a plurality of longitudinally arranged stirring rods (10) are installed on the horizontal frame (9). An internal heat exchange assembly is provided inside the vertical tube (4). Multiple circumferentially distributed protrusions (5) are evenly spaced on the inner wall of the reactor body (1); The two sides of the protrusion (5) are connected to the inner wall of the reactor body (1) by a slope (27), and the inner wall of the reactor body (1) is provided with an external heat exchange component.

2. The gradient temperature and pressure swing reactor for preparing furfural composite catalyst according to claim 1, characterized in that, The internal heat exchange assembly includes an end cap (13) rotatably connected to the upper port of the vertical pipe (4), an inner tube (14) extending into the vertical pipe (4) is fixedly installed on the end cap (13), a heat exchange cavity (29) is formed between the outer wall of the inner tube (14) and the inner wall of the vertical pipe (4), and an output pipe (15) is fixedly connected to the upper end of the end cap (13).

3. The gradient temperature and pressure swing reactor for preparing furfural composite catalyst according to claim 1, characterized in that, The external heat exchange assembly includes a cavity (6) opened in the reactor body (1). The cavity (6) is shaped like a plum blossom under the action of the protrusion (5). The upper and lower outer walls of the reactor body (1) are respectively fixedly connected to an inlet pipe (7) and an outlet pipe (8). Both the inlet pipe (7) and the outlet pipe (8) are connected to the cavity (6).

4. The gradient temperature and pressure swing reactor for preparing furfural composite catalyst according to claim 1, characterized in that, The outer wall of the vertical tube (4) is provided with a slot (30), and the horizontal frame (9) is slidably installed in the slot (30). The vertical tube (4) is provided with a limiting plate (16) fixedly connected to the end of the horizontal frame (9). A spring (17) is installed between the limiting plate (16) and the inner wall of the vertical tube (4). The horizontal frame (9) is pushed against the inner wall of the reactor body (1) under the elastic force of the spring (17).

5. The gradient temperature and pressure swing reactor for preparing furfural composite catalyst according to claim 4, characterized in that, The end of the crossbar (9) is rotatably mounted with a rotating tube (18) that fits against the inner wall of the reactor body (1), and a spiral blade (19) is fixedly mounted on the inner wall of the rotating tube (18).

6. The gradient temperature and pressure swing reactor for preparing furfural composite catalyst according to claim 5, characterized in that, The top of the rotating tube (18) is rotatably mounted with a downwardly bent tube (20), which is fixedly connected to the cross frame (9) via a connecting frame (21).

7. The gradient temperature and pressure swing reactor for preparing furfural composite catalyst according to claim 1, characterized in that, The stirring rod (10) has a rectangular cross-sectional shape and is inclinedly arranged on the cross frame (9). An inclined flow channel (28) is formed between two adjacent stirring rods (10), so that multiple stirring rods (10) are distributed on the cross frame (9) in an inverted V-shape.

8. The gradient temperature and pressure swing reactor for preparing furfural composite catalyst according to claim 4, characterized in that, Both sides of the crossbar (9) are fixedly connected to supports (22), and each of the two supports (22) is rotatably mounted with a crossbar (24) via a pivot (23). The end of the crossbar (24) is fixedly connected to a scraper (25). A torsion spring is installed between the pivot (23) and the support (22), and the elastic force of the torsion spring causes the scraper (25) to adhere to the outer wall of the vertical tube (4).

9. A gradient temperature and pressure swing reactor for preparing furfural composite catalyst according to claim 1, characterized in that, A drive motor (11) is fixedly installed on the reactor body (1). The output shaft of the drive motor (11) and the outer wall of the vertical tube (4) are both fixedly installed with transmission gears (12), and the two transmission gears (12) are meshed together.

10. A method for controlling a gradient temperature-pressure swing reactor for the preparation of furfural composite catalysts, characterized in that, The gradient temperature-pressure swing reactor used in the preparation of furfural composite catalyst as described in any one of claims 1-9 comprises the following steps: S1: Loading and airtightness check The composite catalyst precursor and solvent are added to the reactor body (1), sealed, and nitrogen is introduced for multiple replacements to purge the air from the reactor body (1). Then, nitrogen or hydrogen at a certain pressure is introduced to test the air tightness and confirm that the system has no leaks. S2: Gradient heating stage The controller heats the reactor body (1) in segments according to a preset temperature-time gradient curve. The gradient heating is not a linear continuous heating, but a step-by-step progressive heating mode: First stage (low temperature activation): Set temperature T1, heating rate r1, hold temperature for t1 after reaching target value to promote the initial decomposition of catalyst precursor. Second stage (intermediate temperature crystallization): Heat to T2 at a rate r2, and hold at a constant temperature t2; The third stage (high temperature reduction / calcination): Under an inert or reducing atmosphere, the temperature is increased to T3 at a rate of r3 and held at a constant temperature of t3 to complete the final shaping of the catalyst. S3: Transformer Co-control Within each isothermal range of the gradient heating, the controller synchronously performs pressure transformation operations; the pressure setpoint is dynamically adjusted according to the temperature range, specifically through the following strategy: In the low-temperature range, a low pressure P1 is maintained to facilitate the removal of solvents or template agents from the precursor. After entering the medium-high temperature section, based on the rate of gas thermal expansion and chemical reaction gas consumption in the reactor body (1), the pressure is increased to P2 or P3 in stages by adjusting the opening of the inlet valve and the outlet valve. S4: Cooling and pressure relief After the reaction is completed, the program controls the cooling water to enter the jacket and coil for cooling. At the same time, the pressure is gradually released according to the set rate. After the temperature drops to a safe range and the pressure returns to zero, the discharge pipe (3) at the bottom of the reactor body (1) is opened to take out the material.

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