Mnmp production apparatus and production method

Abstract

The application discloses MNMP production device and production method, relates to the MNMP production technical field;And the application includes reaction box, the top of reaction box is equipped with a pair of material injection mechanism, one side of material injection mechanism is equipped with connecting hose, the inside of material injection mechanism is equipped with feeding mechanism, the inside of reaction box is fixedly connected with heating plate, the inside of heating plate is equipped with sealing moving plate, the outer wall of sealing moving plate is fixedly connected with sealing ring, and the outer wall of sealing ring is in interference fit with the inner wall of sealing ring;Through the attempt of increasing hydrogen pressure, the selectivity of target product MNMP is greatly improved, which is more conducive to product purification treatment, and the addition of several important parameters, hydrogen pressure, temperature, time, the addition ratio of raw material acetylpregalic acid ester and methylamine in the hydrogenation process, process optimization can realize MNMP high selectivity preparation.

Description

Technical Field

[0001] This invention relates to the field of MNMP production technology, specifically to MNMP production apparatus and production method. Background Technology

[0002] To avoid excessive system pressure caused by the decomposition of formic acid as a hydrogen source to produce CO2, and to achieve the industrial-scale preparation of 1,5-dimethyl-2-pyrrolidone, the hydrogen method of hydrogenation is also the cheapest hydrogenation method in industry. Therefore, we tried to use a hydrogen source catalytic hydrogenation process to prepare MNMP. The source of the hydrogenation catalyst is the industrially applied hydrogenation catalyst, which can be obtained in large quantities.

[0003] The existing technology has the following problems:

[0004] During the process exploration stage, the hydrogen pressure addition was only at a low pressure level, but the poor product selectivity brought great difficulties to the subsequent product purification. At the same time, the sealing of the device was not very good, and the entry of air would affect the production results. In order to solve the above problems, the inventors proposed an MNMP production device and production method. Summary of the Invention

[0005] In order to solve the problem that the existing MNMP production equipment and methods do not produce very good results, the purpose of this invention is to provide an MNMP production equipment and method.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: an MNMP production apparatus and production method, including a reaction chamber, a pair of material injection mechanisms above the reaction chamber, a connecting hose on one side of the material injection mechanism, a feeding mechanism inside the material injection mechanism, a heating plate fixedly connected inside the reaction chamber, a sealing moving plate inside the heating plate, a sealing ring fixedly connected to the outer wall of the sealing moving plate, and the outer wall of the sealing ring and the inner wall of the sealing ring are interference fit, a filter plate fixedly connected to the upper part of the reaction chamber, an extension opening through one side of the upper surface of the filter plate, a gas extraction pipe and a hydrogen pipe symmetrically provided on the upper surface of the filter plate, the ends of the gas extraction pipe and the hydrogen pipe away from the connecting pipe respectively penetrating the filter plate and the sealing moving plate, and both the gas extraction pipe and the hydrogen pipe are fixedly connected to the sealing moving plate.

[0007] Preferably, multiple supports are fixedly connected to the lower end face of the reaction chamber, and a connected discharge pipe is fixedly connected to one side of the lower end face of the reaction chamber. A stirring rod is provided at the bottom of the reaction chamber. A motor is fixedly connected to the center of the bottom of the reaction chamber. The output end of the motor extends into the interior of the reaction chamber and is fixedly connected to the stirring rod. A first limiting ring is fixedly connected to the upper end face of the heating plate, and a second limiting ring is fixedly connected to the lower end face of the heating plate. A connecting groove is provided through one side of the upper end face of the second limiting ring. The other ends of the exhaust pipe and the hydrogen pipe are fixedly connected to connecting pipes.

[0008] Preferably, the material injection mechanism includes a material box fixedly connected to the upper surface of the filter screen plate, a scale plate fixedly connected to the outer wall of the material box, a mesh plate fixedly connected to the upper surface of the material box, a support block fixedly connected to the lower part of the inner cavity of the material box, an injection pipe fixedly connected to the upper surface of the support block, a lightweight floating plate slidably connected to the outer wall of the injection pipe, a silicone ring fixedly connected to the outer wall of the lightweight floating plate, multiple communicating holes connected to the inside of the injection pipe being opened on the lower outer wall of the injection pipe, a connection port being opened through the upper surface of the mesh plate, a connection port extending from the upper end of the injection pipe, a funnel frame fixedly connected to the upper end of the injection pipe, a connected water outlet pipe fixedly connected to the lower part of the end of the material box away from the scale plate, a combined pipe fixedly connected between the two water outlet pipes, and a connecting hose fixedly connected to the combined pipe and communicating with each other.

[0009] Preferably, the feeding mechanism includes a fixed tube that passes through and is fixedly connected to the sealing movable plate. A fixed plate that communicates with each other is fixedly connected to the lower end face of the fixed tube. A diversion plate is provided below the fixed plate. A fixed frame is fixedly connected to the periphery between the fixed plate and the diversion plate. A slot is provided on the side wall of the diversion plate. An insert plate is movably inserted into the slot. A pair of connecting blocks are fixedly connected to the end of the insert plate away from the diversion plate. An arc-shaped sleeve is fixedly connected to one end of the connecting block. A ball head is movably engaged inside the arc-shaped sleeve. A connected sealing valve is fixedly connected to the upper end face of the fixed tube. The sealing valve is fixedly connected to and communicates with the connecting hose. Multiple springs are fixedly connected inside the slot, and spring insert plates are fixedly connected.

[0010] The MNMP process development and production method includes the following production steps:

[0011] Step 1: Conduct a catalyst-free comparative reaction at 160 °C under normal pressure and hydrogen atmosphere for 6 h;

[0012] Step 2: Conduct a comparative reaction with catalysis, adding a catalyst and reacting for 6 h at 160 °C under normal pressure and hydrogen atmosphere;

[0013] Step 3: Conduct comparative reactions of catalytic hydrogenation, with catalysts reacting under different hydrogen pressure conditions;

[0014] Step 4: Integrate the above steps, analyze the conversion rate of levulinic acid and the selectivity of MNMP, and optimize the MNMP production process.

[0015] In step three, the method for controlling hydrogen conditions at different pressures is as follows:

[0016] Preferably, the proportioned solution of the production reactants is injected into the injection tube through the funnel frame. The proportioned solution is discharged through multiple connecting holes at the bottom of the injection tube. As the water level of the proportioned solution rises, it will lift the lightweight floating plate. The proportion of the proportioned solution inside the two scale plates is controlled by observing the scale plates. After the proportioned solution is injected, the connecting pipe on the vacuum pipe is installed on the vacuum pump. Then, the connecting pipe on the hydrogen pipe is installed on the hydrogen cylinder. First, the vacuum pump is started. The vacuum pump works to extract the air inside the reaction chamber. As the air inside the reaction chamber decreases, the sealing moving plate inside the reaction chamber moves into the second limiting ring until the sealing moving plate contacts the second limiting ring. Then, the inside of the reaction chamber is completely evacuated into a vacuum. The inner cavity of the reaction chamber is located below the second limiting ring as the liquid reaction chamber.

[0017] The heating plate on the inner wall of the reaction chamber is activated, releasing heat. The sealing valve is fixedly connected to the connecting hose and the fixed pipe, which in turn connect to the combined pipe. Opening the sealing valve allows the mixed solution from both material tanks to be drawn into the fixed pipe under negative pressure. The solution then flows down the fixed pipe onto the guide plate. One end of the guide plate is movably connected to an insert plate, which is fixed with a connecting block and an arc-shaped sleeve. The spherical head inside the arc-shaped sleeve contacts the inner wall of the reaction chamber, creating a certain gap between the insert plate and the inner wall. The mixed solution flows along the guide plate and insert plate towards the inner wall of the reaction chamber, eventually flowing down to the bottom of the chamber to prevent air bubbles from entering, until the mixed solution is completely dissolved. The liquid enters the reaction chamber, and the lightweight floating plate contacts the bottom of the material tank. A silicone ring blocks the outlet pipe to prevent air from entering. Then, the motor is started, which drives the output end to rotate. The rotation of the output end drives the stirring rod to rotate, ensuring that the mixed liquid is fully blended. Then, the hydrogen cylinder is opened, and hydrogen enters the reaction chamber. The sealing moving plate inside the reaction chamber moves towards the first limiting ring until the sealing moving plate contacts the first limiting ring. Hydrogen fills the inside of the reaction chamber, thus initiating the reaction. The movement of the sealing moving plate drives the feeding mechanism to move. When the insert plate moves into the heating plate, the spherical head contacts the inner wall of the heating plate, and one end of the insert plate enters the slot, causing the spring to contract.

[0018] Preferably, between each reaction step, the residue in the reaction chamber needs to be removed. The removal method is as follows:

[0019] Open the gas valve on the vacuum pump to release the hydrogen, then open the discharge pipe at the bottom of the reaction chamber to discharge the reaction residue, and clean the reaction chamber. Repeat the above operations to refill the material and resume production.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] 1. By increasing the hydrogen pressure, the selectivity of the target product MNMP was significantly improved, which is more conducive to product purification. In the hydrogenation process, the addition of several important parameters such as hydrogen pressure, temperature, time, and the addition ratio of raw materials levulinate and methylamine can achieve high-selectivity preparation of MNMP.

[0022] 2. By installing a sealing moving plate inside the reaction chamber, the proportioned solution of the production reactants is injected into the injection pipe through a funnel frame. As the water level of the proportioned solution rises, it lifts the lightweight floating plate. The vacuum pump operates to extract the air from inside the reaction chamber. With the air reduced, the sealing moving plate inside the reaction chamber moves towards the second limiting ring until it contacts the second limiting ring. Then, the inside of the reaction chamber is completely evacuated to a vacuum. Under negative pressure, the proportioned solution from the two material tanks is drawn into the fixed pipe and falls onto the guide plate. One end of the flow guide plate is movably connected to an insert plate, on which a connecting block and an arc-shaped sleeve are fixed. The spherical head inside the arc-shaped sleeve contacts the inner wall of the reaction chamber, creating a certain gap between the insert plate and the inner wall of the reaction chamber. The solution flows along the flow guide plate and the insert plate to the inner wall of the reaction chamber, and then flows along the inner wall to the bottom of the reaction chamber, preventing air bubbles from entering. This continues until the solution has completely entered the liquid reaction chamber. Vacuum extraction prevents air from entering the interior of the reaction chamber. At the same time, the solution flows along the inner wall of the reaction chamber, preventing liquid collisions that could generate a large number of air bubbles, thus avoiding impact on subsequent production. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0025] Figure 2 This is a schematic diagram of the rear structure of the present invention.

[0026] Figure 3 This is a schematic diagram of the internal structure of the material injection mechanism of the present invention.

[0027] Figure 4 For the present invention Figure 3 A magnified view of a portion of area A.

[0028] Figure 5 This is a cross-sectional view of the lightweight floating plate of the present invention.

[0029] Figure 6 This is a schematic diagram of the internal structure of the reaction chamber of the present invention.

[0030] Figure 7 This is a cross-sectional view of the feeding mechanism of the present invention.

[0031] In the diagram: 1. Reaction chamber; 2. Support frame; 3. Material injection mechanism; 4. Connecting hose; 5. Feeding mechanism; 6. Heating plate; 7. First limiting ring; 8. Second limiting ring; 9. Connecting groove; 10. Stirring rod; 11. Motor; 12. Discharge pipe; 13. Extraction pipe; 14. Hydrogen pipe; 15. Connecting pipe; 16. Filter plate; 17. Extension port; 18. Sealing moving plate; 19. Sealing ring; 301. Material box; 302. Scale plate; 303. Grid plate 304. Connecting port; 305. Injection pipe; 306. Funnel frame; 307. Lightweight floating plate; 308. Outlet pipe; 309. Combined pipe; 310. Support block; 311. Connecting hole; 312. Silicone ring; 501. Fixing pipe; 502. Sealing valve; 503. Fixing plate; 504. Drain plate; 505. Fixing frame; 506. Slot; 507. Insert plate; 508. Connecting block; 509. Arc sleeve; 510. Spherical head; 511. Spring. Detailed Implementation

[0032] 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.

[0033] Example: Figure 1-7 As shown, the present invention provides a technical solution: an MNMP production apparatus and production method, including a reaction chamber 1. A pair of material injection mechanisms 3 are provided above the reaction chamber 1. A connecting hose 4 is provided on one side of the material injection mechanism 3. A feeding mechanism 5 is provided inside the material injection mechanism 3. A heating plate 6 is fixedly connected inside the reaction chamber 1. A sealing moving plate 18 is provided inside the heating plate 6. A sealing ring 19 is fixedly connected to the outer wall of the sealing moving plate 18. The outer wall of the sealing ring 19 and the inner wall of the sealing ring 19 are interference fit, which plays a good sealing role. A filter plate 16 is fixedly connected to the upper part of the reaction chamber 1. An extension port 17 is opened through one side of the upper end face of the filter plate 16. A suction pipe 13 and a hydrogen pipe 14 are symmetrically provided on the upper end face of the filter plate 16. The ends of the suction pipe 13 and the hydrogen pipe 14 away from the connecting pipe 15 pass through the filter plate 16 and the sealing moving plate 18 respectively. The suction pipe 13 and the hydrogen pipe 14 are both fixedly connected to the sealing moving plate 18.

[0034] Multiple supports 2 are fixedly connected to the lower end face of the reaction chamber 1. A discharge pipe 12 is fixedly connected to one side of the lower end face of the reaction chamber 1. A stirring rod 10 is provided at the bottom inside the reaction chamber 1. A motor 11 is fixedly connected to the center of the bottom of the reaction chamber 1. The output end of the motor 11 extends into the interior of the reaction chamber 1 and is fixedly connected to the stirring rod 10. A first limiting ring 7 is fixedly connected to the upper end face of the heating plate 6. A second limiting ring 8 is fixedly connected to the lower end face of the heating plate 6. A connecting groove 9 is provided through one side of the upper end face of the second limiting ring 8 to facilitate the movement of the feeding mechanism 5. A connecting pipe 15 is fixedly connected to the other end of the exhaust pipe 13 and the hydrogen pipe 14.

[0035] The material injection mechanism 3 includes a material box 301 fixedly connected to the upper end face of the filter screen plate 16. A scale plate 302 is fixedly connected to the outer wall of the material box 301. A mesh plate 303 is fixedly connected to the upper end face of the material box 301. A support block 310 is fixedly connected to the lower part of the inner cavity of the material box 301. An injection pipe 305 is fixedly connected to the upper end face of the support block 310. A lightweight floating plate 307 is slidably connected to the outer wall of the injection pipe 305. A silicone ring 312 is fixedly connected to the outer wall of the lightweight floating plate 307. The lower end of the injection pipe 305... The wall has multiple connecting holes 311 that communicate with the inside of the injection pipe 305. The upper end face of the grid plate 303 has a through-hole 304. The upper end of the injection pipe 305 extends out of the connecting hole 304. The upper end of the injection pipe 305 is fixedly connected to the funnel frame 306. The lower end of the material box 301 away from the scale plate 302 is fixedly connected to the water outlet pipe 308. The two water outlet pipes 308 are fixedly connected to the combination pipe 309. The connecting hose 4 is fixedly connected to the combination pipe 309 and communicates with each other to facilitate liquid flow.

[0036] The feeding mechanism 5 includes a fixed tube 501 that passes through and is fixedly connected to the sealing movable plate 18. A fixed plate 503 that communicates with the fixed tube 501 is fixedly connected to the lower end face of the fixed tube 501. A flow guide plate 504 is provided below the fixed plate 503. A fixed frame 505 is fixedly connected to the periphery between the fixed plate 503 and the flow guide plate 504. A slot 506 is provided on the side wall of the flow guide plate 504. An insert plate 507 is movably inserted into the slot 506. A pair of connecting blocks 508 are fixedly connected to the end of the insert plate 507 away from the flow guide plate 504. One end of the connecting block 508 is fixedly connected to... There is an arc-shaped sleeve 509, and a ball head 510 is movably engaged inside the arc-shaped sleeve 509. A sealing valve 502 is fixedly connected to the upper end face of the fixed tube 501. The sealing valve 502 is fixedly connected to and communicates with the connecting hose 4. Multiple springs 511 are fixedly connected inside the slot 506, and the springs 511 are fixedly connected to the insert plate 507. When the insert plate 507 moves into the heating plate 6, the ball head 510 contacts the inner wall of the heating plate 6, one end of the insert plate 507 enters the interior of the slot 506, the springs 511 contract, and the ball head 510 contacts the inner wall of the heating plate 6.

[0037] The MNMP process development and production method includes the following production steps:

[0038] Step 1: Conduct a catalyst-free comparative reaction at 160 °C under normal pressure and hydrogen atmosphere for 6 h;

[0039] Step 2: Conduct a comparative reaction with catalysis, adding a catalyst and reacting for 6 h at 160 °C under normal pressure and hydrogen atmosphere;

[0040] Step 3: Conduct comparative reactions of catalytic hydrogenation, with catalysts reacting under different hydrogen pressure conditions;

[0041] Step 4: Integrate the above steps, analyze the conversion rate of levulinic acid and the selectivity of MNMP, and optimize the MNMP production process.

[0042] In step three, the method for controlling hydrogen conditions at different pressures is as follows:

[0043] The proportioned solution of the production reactants is injected into the injection tube 305 through the funnel frame 306. The proportioned solution is discharged through multiple connecting holes 311 at the bottom of the injection tube 305. As the water level of the proportioned solution rises, it will lift the lightweight floating plate 307. The proportion of the proportioned solution inside the two scale plates 302 is controlled by observing the scale plate 302. After the proportioned solution is injected, the connecting pipe 15 on the vacuum pipe 13 is installed on the vacuum pump. Then, the connecting pipe 15 on the hydrogen pipe 14 is installed on the hydrogen cylinder. First, the vacuum pump is started. The vacuum pump works to extract the air inside the reaction chamber 1. As the air inside the reaction chamber 1 decreases, the sealing moving plate 18 inside the reaction chamber 1 moves into the inside of the second limiting ring 8 until the sealing moving plate 18 contacts the second limiting ring 8. Then, the inside of the reaction chamber 1 is completely evacuated into a vacuum. The inner cavity of the reaction chamber 1 is located below the second limiting ring 8 and is the liquid reaction chamber.

[0044] The heating plate 6 on the inner wall of reaction chamber 1 is activated, releasing heat. The sealing valve 502 is fixedly connected to the connecting hose 4 and the fixed pipe 501, respectively. The connecting hose 4 is connected to the combination pipe 309. Opening the sealing valve 502, under negative pressure, the proportioned liquid inside the two material boxes 301 is drawn into the fixed pipe 501. The proportioned liquid flows down the fixed pipe 501 onto the guide plate 504. One end of the guide plate 504 is movably connected to an insert plate 507. A connecting block 508 and an arc-shaped sleeve 509 are fixed on the insert plate 507. The spherical head 510 inside the arc-shaped sleeve 509 contacts the inner wall of reaction chamber 1, creating a certain gap between the insert plate 507 and the inner wall of reaction chamber 1. The proportioned liquid flows along the guide plate 504 and the insert plate 507 towards the inner wall of reaction chamber 1, and then flows down the inner wall of reaction chamber 1 to the bottom, preventing air bubbles from forming. The mixture is introduced until the solution is completely introduced into the liquid reaction chamber. The lightweight floating plate 307 contacts the bottom of the material box 301. The silicone ring 312 blocks the water outlet pipe 308 to prevent air from entering. Then, the motor 11 is started. The motor 11 drives the output end to rotate, which in turn drives the stirring rod 10 to rotate. The rotation of the stirring rod 10 makes the solution fully mixed. Then, the hydrogen cylinder is opened, and hydrogen enters the interior of the reaction chamber 1. The sealing moving plate 18 inside the reaction chamber 1 moves towards the interior of the first limiting ring 7 until the sealing moving plate 18 contacts the first limiting ring 7. The hydrogen fills the interior of the reaction chamber 1, thus causing a reaction. The movement of the sealing moving plate 18 drives the feeding mechanism 5 to move. When the insert plate 507 moves into the interior of the heating plate 6, the ball head 510 contacts the inner wall of the heating plate 6, and one end of the insert plate 507 enters the interior of the slot 506. The spring 511 contracts.

[0045] Open the gas valve on the vacuum pump to release the hydrogen gas, then open the discharge pipe 12 at the bottom of the reaction chamber 1 to discharge the reaction residue, and clean the reaction chamber 1. Repeat the above operation to refill the material and start production.

[0046] The specific production ratio is as follows:

[0047]

[0048] MNMP is prepared by purchasing industrial catalysts and using a hydrogen source for the catalytic reduction and amination of levulinic acid (ester).

[0049] Production ratio 1 was used as a comparative reaction without the addition of a catalyst. The target product MNMP showed poor selectivity. Under hydrogen conditions at 160 °C for 6 h, the conversion rate of levulinic acid was 78%, and the selectivity of MNMP was 22%.

[0050] Production ratios 2-4 involve catalytic hydrogenation. The catalyst is Aladdin Raney nickel catalyst, purchased in small quantities at the production ratio chamber level. The reaction is carried out at 160 °C and 1 MPa hydrogen pressure for 6 h, with a levulinic acid conversion rate of 100% and an MNMP selectivity of 71%.

[0051] Production ratio 5 uses Raney nickel catalyst, manufactured by Changzhou Feima Company, for industrial-scale applications. Under conditions of 160 °C and 1 MPa hydrogen pressure for 6 h, the conversion rate of levulinic acid is 100%, and the MNMP selectivity reaches 82%. Production ratio 6 further increases the hydrogen pressure to 2 MPa, achieving a MNMP selectivity of 96%. This high selectivity essentially achieves complete conversion of the raw material to the target product, although trace amounts of byproducts remain. Further optimization of key parameters such as reaction hydrogen pressure, reaction time, and reaction temperature resulted in production ratio 9, reacting at 170 °C and 2 MPa hydrogen pressure for 6 h, further increasing the MNMP selectivity to 97%. Based on the currently optimized process parameters, 2 MPa hydrogen pressure is preliminarily determined to be the optimal hydrogen pressure. Further increasing the hydrogen pressure (production ratios 13 and 14) and extending the reaction time (production ratio 15) may lead to over-hydrogenation and the generation of byproducts, resulting in a slight decrease in MNMP selectivity.

[0052] Production ratio 16 uses methyl levulinate as raw material to prepare MNMP by hydrogenation. The reaction is carried out at 160 °C and 2 MPa hydrogen pressure for 6 h. The selectivity of MNMP is 95%, which is comparable to that of levulinate as raw material.

[0053] Production ratios 17 and 18 use two types of industrial-grade Raney nickel catalysts produced by Shanghai Xunkai Company. The Raney nickel-1000 catalyst has a similar catalytic effect to the Raney nickel catalyst produced by Changzhou Feima Company, but the Raney nickel-1200 catalyst has a significantly reduced catalytic effect.

[0054] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. An MNMP production apparatus, comprising a reaction chamber (1), characterized in that: A pair of material injection mechanisms (3) are provided above the reaction chamber (1). A connecting hose (4) is provided on one side of the material injection mechanism (3). A feeding mechanism (5) is provided inside the material injection mechanism (3). A heating plate (6) is fixedly connected inside the reaction chamber (1). A sealing moving plate (18) is provided inside the heating plate (6). A sealing ring (19) is fixedly connected to the outer wall of the sealing moving plate (18), and the outer wall of the sealing ring (19) is press-fitted with the inner wall of the reaction chamber (1). The reaction chamber (1) is fixedly connected to the upper part of the interior. An extension port (17) is opened through one side of the upper surface of the filter plate (16). The upper surface of the filter plate (16) is symmetrically provided with a gas extraction pipe (13) and a hydrogen pipe (14). The ends of the gas extraction pipe (13) and the hydrogen pipe (14) away from the connecting pipe (15) respectively pass through the filter plate (16) and the sealing moving plate (18), and the gas extraction pipe (13) and the hydrogen pipe (14) are fixedly connected to the sealing moving plate (18). The material injection mechanism (3) includes a material box (301) fixedly connected to the upper end face of the filter plate (16), a scale plate (302) fixedly connected to the outer wall of the material box (301), a mesh plate (303) fixedly connected to the upper end face of the material box (301), a support block (310) fixedly connected to the lower part of the inner cavity of the material box (301), an injection pipe (305) fixedly connected to the upper end face of the support block (310), a lightweight floating plate (307) slidably connected to the outer wall of the injection pipe (305), a silicone ring (312) fixedly connected to the outer wall of the lightweight floating plate (307), and a plurality of communicating holes (311) connected to the inside of the injection pipe (305) on the lower end of the outer wall. The upper end face of the grid plate (303) is provided with a connection port (304), the upper end of the injection pipe (305) extends out of the connection port (304), the upper end of the injection pipe (305) is fixedly connected to a funnel frame (306), the lower end of the material box (301) away from the scale plate (302) is fixedly connected to a connected water outlet pipe (308), a combination pipe (309) is fixedly connected between the two water outlet pipes (308), and the connecting hose (4) is fixedly connected to the combination pipe (309) and communicates with each other; The feeding mechanism (5) includes a fixed tube (501) that passes through and is fixedly connected to the sealing moving plate (18). The lower end face of the fixed tube (501) is fixedly connected to a fixed plate (503) that communicates with each other. A diversion plate (504) is provided below the fixed plate (503). A fixed frame (505) is fixedly connected to the periphery between the fixed plate (503) and the diversion plate (504). A slot (506) is provided on the side wall of the diversion plate (504). An insert plate (507) is movably inserted into the slot (506). A pair of connecting blocks (508) are fixedly connected to one end of the insert plate (507) away from the diversion plate (504). An arc sleeve (509) is fixedly connected to one end of the connecting block (508). A ball head (510) is movably engaged inside the arc sleeve (509).

2. The MNMP production apparatus as described in claim 1, characterized in that, The lower end face of the reaction chamber (1) is fixedly connected to multiple supports (2), and a discharge pipe (12) is fixedly connected to one side of the lower end face of the reaction chamber (1). A stirring rod (10) is provided at the bottom inside the reaction chamber (1). A motor (11) is fixedly connected to the center of the bottom of the reaction chamber (1). The output end of the motor (11) extends into the interior of the reaction chamber (1) and is fixedly connected to the stirring rod (10).

3. The MNMP production apparatus as described in claim 2, characterized in that, The upper end face of the heating plate (6) is fixedly connected to a first limiting ring (7), and the lower end face of the heating plate (6) is fixedly connected to a second limiting ring (8). A connecting groove (9) is opened through one side of the upper end face of the second limiting ring (8), and the other end of the exhaust pipe (13) and the hydrogen pipe (14) are both fixedly connected to a connecting pipe (15).

4. The MNMP production apparatus as described in claim 3, characterized in that, The upper end face of the fixed tube (501) is fixedly connected to a connected sealing valve (502). The sealing valve (502) is fixedly connected to the connecting hose (4) and communicates with each other. The slot (506) is fixedly connected to a plurality of springs (511), and the springs (511) are fixedly connected to the insert plate (507).

5. A production method using the MNMP production apparatus of claim 4, characterized in that, The production process includes the following steps: Step 1: A hydrogen source was used to catalyze the reduction amination of levulinic acid to prepare MNMP. A catalyst-free comparative reaction was carried out at 160 °C under normal pressure and hydrogen conditions for 6 h. Step 2: Conduct a comparative reaction with a catalyst, and react with the catalyst at 160 °C under normal pressure and hydrogen atmosphere for 6 h; Step 3: Conduct comparative hydrogenation reactions with and without catalysts, adding catalysts under different hydrogen pressure conditions; Step 4: Analyze the conversion rate of levulinic acid and the selectivity of MNMP; the catalyst is Raney nickel.

6. The production method as described in claim 5, characterized in that, In step three, the method for controlling hydrogen conditions at different pressures is as follows: The reaction mixture is injected into the injection tube (305) through the funnel frame (306). The mixture is discharged through multiple connecting holes (311) at the bottom of the injection tube (305). As the water level of the mixture rises, it will lift the lightweight floating plate (307). The ratio of the mixture inside the two scale plates (302) is controlled by observing the scale plate (302). After the mixture is injected, the connecting pipe (15) on the suction pipe (13) is installed on the suction pump, and then hydrogen is injected. The connecting pipe (15) on the tube (14) is installed on the hydrogen cylinder. First, start the vacuum pump. The vacuum pump works to extract the air inside the reaction chamber (1). As the air inside the reaction chamber (1) decreases, the sealing moving plate (18) inside the reaction chamber (1) moves into the inside of the second limiting ring (8) until the sealing moving plate (18) contacts the second limiting ring (8). Then, the inside of the reaction chamber (1) is completely evacuated into a vacuum. The inner cavity of the reaction chamber (1) is located below the second limiting ring (8) as a liquid reaction chamber. The heating plate (6) on the inner wall of the reaction chamber (1) is activated. The heating plate (6) releases heat. The sealing valve (502) is fixedly connected to the connecting hose (4) and the fixed pipe (501) respectively. The connecting hose (4) is connected to the combined pipe (309). The sealing valve (502) is opened. Under the action of negative pressure, the proportioned liquid inside the two material tanks (301) will be sucked into the interior of the fixed pipe (501). The proportioned liquid will fall into the guide plate (504) along the fixed pipe (501). The guide plate (504) One end of the container is movably connected to a plate (507). A connecting block (508) and an arc-shaped sleeve (509) are fixed on the plate (507). The spherical head (510) inside the arc-shaped sleeve (509) contacts the inner wall of the reaction chamber (1), so that there is a certain gap between the plate (507) and the inner wall of the reaction chamber (1). The solution flows along the guide plate (504) and the plate (507) to the inner wall of the reaction chamber (1). The solution flows along the inner wall of the reaction chamber (1) to the bottom of the reaction chamber (1), preventing... Air bubbles are introduced until the mixture is completely introduced into the liquid reaction chamber. The lightweight floating plate (307) contacts the bottom of the material tank (301). The silicone ring (312) blocks the water outlet pipe (308) to prevent air from entering. Then the motor (11) is started. The motor (11) drives the output end to rotate. The rotation of the output end drives the stirring rod (10) to rotate. The rotation of the stirring rod (10) makes the mixture fully mixed. Then the hydrogen cylinder is opened, and hydrogen enters the interior of the reaction chamber (1). The internal sealing moving plate (18) moves into the first limiting ring (7) until the sealing moving plate (18) contacts the first limiting ring (7), and hydrogen fills the interior of the reaction chamber (1), thus causing a reaction. The movement of the sealing moving plate (18) drives the feeding mechanism (5) to move. When the insert plate (507) moves into the interior of the heating plate (6), the ball head (510) contacts the inner wall of the heating plate (6), and one end of the insert plate (507) enters the interior of the slot (506), and the spring (511) contracts.

7. The production method as described in claim 6, characterized in that, Between each reaction step, the residue in the reaction chamber (1) needs to be removed. The removal method is as follows: Open the gas valve on the vacuum pump to discharge the hydrogen gas, then open the discharge pipe (12) below the reaction chamber (1) to discharge the reaction residue, and clean the reaction chamber (1). Repeat steps one to four to refill the material for production.

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