A process for the production of methyl acrylate and related equipment

Abstract

The application discloses a kind of methyl acrylate production process and related equipment, it is related to methyl acrylate production technical field.The reaction kettle is top end fixedly connected with one outlet pipe, and the bottom of the reaction kettle is fixedly connected with feed pipe.The present application is provided with shunt component, variable volume component and power device, power device provides power for shunt component and variable volume component, and the flow guide piece is guided to one of the parallel double tubes, and the flow guide piece at the other end of the parallel double tubes closes the gas outlet end of the pipeline, to ensure the area sealing, at the same time, power device moves No.1 piston through transmission, to increase the volume of the pipeline, so that methanol can enter the pipeline, and continuously maintain the sealed state, to improve the contact time between methanol, acrylic acid and catalytic layer, to ensure sufficient contact between methanol and acrylic acid, to improve the single utilization rate of methanol, to reduce the subsequent recovery cost of methanol.

Description

Technical Field

[0001] This invention relates to the field of methyl acrylate production technology, specifically to a methyl acrylate production process and related equipment. Background Technology

[0002] Methyl acrylate is an important organic compound widely used in the manufacture of plastics, fibers and other chemicals. Methyl acrylate can be produced by esterification of methanol and acrylic acid.

[0003] In the process of producing methyl acrylate from methanol and acrylic acid through esterification, byproducts are generated, and their presence directly affects the conversion rate of methyl acrylate. This reaction is reversible. To promote the conversion of methanol and acrylic acid into methyl acrylate and water, it is necessary to remove methyl acrylate and water from the reactor in a timely manner to reduce their content. However, since the boiling point of methanol is between that of methyl acrylate and water, controlling the internal temperature of the reactor when removing methyl acrylate will lead to methanol loss, thereby reducing the production rate of methyl acrylate and even affecting its conversion rate. Therefore, it is necessary to continuously feed methanol into the reactor. However, methanol will vaporize and rise due to temperature, resulting in a short contact time with acrylic acid. Although methanol can be recycled, insufficient contact with acrylic acid leads to low single-use efficiency of methanol and increases the cost of methanol recovery. To address this, a reactor for methyl acrylate production and a corresponding production process have been invented. Summary of the Invention

[0004] The purpose of this invention is to provide a process and related equipment for the production of methyl acrylate, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a reactor for the production of methyl acrylate, comprising a reaction vessel, wherein a gas outlet pipe is fixedly connected to the top of the reaction vessel, a feed pipe is fixedly connected to the bottom of the reaction vessel, and a flow divider is installed at the bottom inside the reaction vessel; The diversion assembly includes two parallel pipes, which are fixedly installed at the bottom of the reactor. The two parallel pipes are inclined as a whole. Diversion pipes are fixedly connected to the outlet and inlet ends of the two parallel pipes. Vertically, the inlet end of the two parallel pipes is lower than the outlet end. Guide elements are rotatably connected inside the two diversion pipes. Turntables are rotatably connected to the top ends of the two diversion pipes. The bottom end of the turntable penetrates the outer wall of the diversion pipe and is fixed to the top end of the guide element. A movable frame is slidably connected to the top end of the diversion pipe. The bottom end of the movable frame is movably connected to the top end of the turntable. A variable volume assembly for controlling the internal volume of the two parallel pipes is installed on the two parallel pipes. A power device for driving the movable frame is installed inside the reactor. The diversion pipe and feed pipe at the bottom of the two parallel pipes are fixed together. A catalyst layer is fixedly connected inside the two parallel pipes.

[0006] Furthermore, a cylinder is fixedly connected to one side of the turntable, and an arc hole is provided on one side of the movable frame. One side of the turntable is slidably connected to one side of the movable frame through the cylinder and the arc hole.

[0007] Furthermore, the parallel dual-pipe system comprises two parallel and mutually fixed pipes, the interiors of which are not interconnected. The variable capacity assembly comprises a cylinder, with cylinders fixedly connected to the outer walls of the two pipes respectively. A piston is fixedly and slidably connected inside the cylinder. A connecting frame is fixedly connected to one end of the piston, and the other end of the connecting frame is fixed to one side of the other piston. The connecting frame is connected to the output end of the power device.

[0008] Furthermore, the power unit includes a No. 1 motor, which is fixedly installed inside the reactor. A disc is fixedly connected to the output end of the No. 1 motor, and a transmission rod is fixedly connected to the bottom end of the disc. The transmission rod is movably connected to the connecting frame and the moving frame, respectively.

[0009] Furthermore, the top of the connecting frame is provided with a contact hole, and the connecting frame is movably connected to the outer wall of the transmission rod through the inner wall of the contact hole. The top of the movable frame is provided with a movable hole, and the movable frame is movably connected to the outer wall of the transmission rod through the inner wall of the movable hole.

[0010] Furthermore, the diversion assembly also includes a diversion plate, the bottom of which is rotatably connected to the bottom of the reactor interior. A partition frame is fixedly connected to the bottom of the reactor interior, the partition frame being divided into several regions that are not interconnected. The inner wall of the partition frame is movably connected to the outer wall of the diversion plate. A material passage hole is provided on the outer wall of the diversion plate, and the interior of the diversion plate is slidably connected to the inner wall of the partition frame through the material passage hole. A connecting pipe is fixedly connected to the outer wall of the partition frame, and a catalyst layer is installed inside the connecting pipe. A rotating sealing disc is rotatably connected to the reactor interior, the bottom of which contacts the gas outlet of the connecting pipe. A volume control assembly for controlling the internal volume of the connecting pipe is installed at the bottom of the reactor interior. A power output device for rotating the diversion plate, the rotating sealing disc, and driving the volume control assembly is installed at the bottom of the reactor interior.

[0011] Furthermore, the capacity control assembly includes a fixed cylinder, which is fixedly installed on the side wall of the connecting pipe. A second piston is slidably connected to the inner wall of the fixed cylinder. A connecting rod is fixedly connected to one side of the second piston. A limiting disc is fixedly connected to the output end of the power output device. The top end of the limiting disc is movably connected to the bottom end of one end of the connecting rod. A movable groove is provided at the top end of the limiting disc, and the top end of the limiting disc is movably connected to the bottom end of one end of the connecting rod through the movable groove.

[0012] Furthermore, the power output device includes a second motor, which is fixedly installed at the bottom of the reactor. The output end of the second motor is fixedly connected to a drive shaft. The top end of the drive shaft passes through the bottom end of the diversion plate and is fixed to the diversion plate. The top end of the drive shaft passes through the bottom end of the diversion plate and is fixed to the bottom end of the rotary sealing plate. The inner wall of the limiting plate is fixed to the outer wall of the drive shaft.

[0013] A process for producing methyl acrylate, employing the aforementioned reactor for methyl acrylate production, wherein the process uses two reactors, and the process includes: S01: Add acrylic acid liquid to the above reaction vessel, remove the air from the reaction vessel, and introduce methanol into the interior of the reaction vessel through the feed pipe. Control the temperature inside the reaction vessel to reach the boiling point of water to obtain mixed gas A. Mixed gas A includes methyl acrylate gas, methanol gas and water vapor. Mixed gas A flows out from the No. 1 outlet pipe of the reaction vessel. After the reaction is completed, the solution in the reaction vessel includes acrylic acid and methyl 3-methoxypropionate. S02: Acrylic acid and methyl 3-methoxypropionate are separated by distillation; S03: Methyl 3-methoxypropionate is concentrated in another reactor, the air in the reactor is removed, and hydrogen is introduced into the reactor through the feed pipe. The temperature of the reactor is controlled to reach the boiling point of water to obtain mixed gas B. Mixed gas B includes hydrogen, methyl acrylate gas, methanol gas and water vapor. Mixed gas B is discharged from the first outlet pipe of the reactor. S04: By using separation methods to separate the various substances in mixed gas A and mixed gas B, methyl acrylate is separated from other substances to obtain methyl acrylate, and methanol and hydrogen are recovered and reused.

[0014] Furthermore, the separation method includes introducing mixed gas A and mixed gas B into a separation tower, controlling the temperature inside the separation tower to decrease, and sequentially achieving phase separation between hydrogen, water, methyl acrylate and methanol.

[0015] Compared with the prior art, the beneficial effects of the present invention are: The equipment for this methyl acrylate process includes a flow splitter, a volumetric modulator, and a power unit. The power unit provides power to the flow splitter and volumetric modulator. A guide vane directs methanol to one of the parallel double pipes, while the guide vane at the other end of the parallel double pipe closes the outlet of that pipe, ensuring a sealed area. Simultaneously, the power unit moves piston number one via transmission, increasing the pipe's volume and allowing methanol to enter while maintaining a sealed state. This increases the contact time between methanol, acrylic acid, and the catalyst layer, ensuring sufficient contact between methanol and acrylic acid, improving the single-use efficiency of methanol, and reducing subsequent methanol recovery costs.

[0016] Meanwhile, the internal temperature of the reactor is set at the boiling point of water. Methanol, methyl acrylate, and water vaporize. As the power unit continues to output power, the guide at the other end opens the outlet of the pipeline. At this time, the volume of the pipeline gradually decreases, the mixed gas A is discharged, and the consumed acrylic acid will re-enter the pipeline from the outlet. The other pipeline enters methanol. The two pipelines can react alternately. With the input of methanol, the production rate of methyl acrylate can be guaranteed.

[0017] The use of the reactor, flow divider, volume changer, and power unit enables it to complete two different reactions in the production process of methyl acrylate: one is the esterification reaction of methanol and acrylic acid to produce methyl acrylate, and the other is the mixed reaction of methyl 3-methoxypropionate and hydrogen to produce methyl acrylate. The reactor and its internal devices can complete the above two reactions, ensuring the effectiveness of the reactor, flow divider, volume changer, and power unit, thereby improving the practicality of the relevant equipment.

[0018] Meanwhile, the production process of methyl acrylate involves collecting the byproducts of the reaction between methanol and acrylic acid to produce methyl acrylate, and concentrating and transporting methyl 3-methoxypropionate to a reaction vessel. In the reaction vessel, methyl 3-methoxypropionate reacts with hydrogen under acidic conditions, thereby converting methyl 3-methoxypropionate into methyl acrylate and methanol. Simultaneously, by controlling the temperature inside the reaction vessel, methyl acrylate and methanol are vaporized and discharged from the reaction vessel. In this way, methyl 3-methoxypropionate can be effectively utilized to produce methyl acrylate again, thereby improving the conversion rate of methyl acrylate. Attached Figure Description

[0019] Figure 1 This is an isometric drawing of Embodiment 1 of the present invention; Figure 2 This is an isometric view of the interior of the reactor in Embodiment 1 of the present invention; Figure 3 This is a cross-sectional view of the variable capacity component and the shunt component according to Embodiment 1 of the present invention; Figure 4 This is an isometric view of the variable capacity assembly, power unit, and flow splitter assembly according to Embodiment 1 of the present invention; Figure 5 This is an isometric drawing of Embodiment 2 of the present invention; Figure 6 This is an isometric drawing of Embodiment 2 of the present invention; Figure 7 This is an isometric view of the shunt assembly according to Embodiment 2 of the present invention; Figure 8 This is an isometric view of the control capacitor assembly according to Embodiment 2 of the present invention; Figure 9 This is a cross-sectional view of the control capacitor assembly according to Embodiment 2 of the present invention; Figure 10 This is an isometric view of the flow divider and partition frame according to Embodiment 2 of the present invention; Figure 11 This is a cross-sectional view of the flow divider and the partition frame according to Embodiment 2 of the present invention.

[0020] In the diagram: 1. Reactor; 2. Variable volume assembly; 201. Cylinder; 202. Piston No. 1; 203. Connecting frame; 3. Power unit; 301. Motor No. 1; 302. Disc; 303. Transmission rod; 4. Diversion assembly; 401. Diversion pipe; 402. Guide component; 403. Turntable; 404. Moving frame; 405. Parallel double pipe; 406. Diversion disc; 407. Separator; 408. Connecting pipe; 409. Rotary sealing disc; 5. Catalytic layer; 6. Volume control assembly; 601. Fixed cylinder; 602. Piston No. 2; 603. Connecting rod; 604. Limiting disc; 7. Power output device; 701. Motor No. 2; 702. Transmission shaft; 8. Partition plate. Detailed Implementation

[0021] 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.

[0022] like Figure 1 - Figure 11 As shown, the present invention provides a technical solution: a reactor for the production of methyl acrylate, including a reaction vessel 1, a gas outlet pipe fixedly connected to the top of the reaction vessel 1, a feed pipe fixedly connected to the bottom of the reaction vessel 1, and a flow divider 4 installed at the bottom inside the reaction vessel 1. The flow divider assembly 4 includes two parallel pipes 405, which are fixedly installed at the bottom inside the reactor 1. The parallel pipes 405 are inclined as a whole. The outlet and inlet ends of the parallel pipes 405 are respectively fixedly connected to flow divider pipes 401. Vertically, the inlet end of the parallel pipes 405 is lower than the outlet end. The interior of each of the two flow divider pipes 401 is rotatably connected to a guide 402. The top ends of each of the two flow divider pipes 401 are rotatably connected to a turntable 403. The bottom end of the turntable 403 penetrates the flow divider pipe. The outer wall of 401 and the top of the guide 402 are fixed together. The top of the diverter 401 is slidably connected to the moving frame 404. The bottom of the moving frame 404 is movably connected to the top of the turntable 403. A variable volume component 2 for controlling the internal volume of the parallel double pipe 405 is installed on the parallel double pipe 405. A power device 3 for driving the moving frame 404 is installed inside the reactor 1. The diverter 401 and the feed pipe at the bottom of the parallel double pipe 405 are fixed together. A catalyst layer 5 is fixedly connected inside the parallel double pipe 405.

[0023] A cylinder is fixedly connected to one side of the turntable 403, and an arc hole is opened on one side of the movable frame 404. One side of the turntable 403 is slidably connected to one side of the movable frame 404 through the cylinder and the arc hole.

[0024] The parallel double pipe 405 includes two parallel pipes that are fixed to each other. The two pipes are not interconnected internally. The variable capacity component 2 includes a cylinder 201. The outer walls of the two pipes are respectively fixedly connected to the cylinder 201. A piston 202 is fixedly and slidably connected inside the cylinder 201. One end of the piston 202 is fixedly connected to a connecting frame 203. The other end of the connecting frame 203 is fixed to one side of the other piston 202. The connecting frame 203 is connected to the output end of the power device 3.

[0025] The power unit 3 includes a first motor 301, which is fixedly installed inside the reactor 1. The output end of the first motor 301 is fixedly connected to a disc 302, and the bottom end of the disc 302 is fixedly connected to a transmission rod 303. The transmission rod 303 is movably connected to the connecting frame 203 and the moving frame 404 respectively.

[0026] The top of the connecting frame 203 has a contact hole, and the connecting frame 203 is movably connected to the outer wall of the transmission rod 303 through the inner wall of the contact hole. The top of the movable frame 404 has a movable hole, and the movable frame 404 is movably connected to the outer wall of the transmission rod 303 through the inner wall of the movable hole.

[0027] The diversion assembly 4 also includes a diversion plate 406, the bottom of which is rotatably connected to the bottom of the interior of the reactor 1. A partition frame 407 is fixedly connected to the bottom of the interior of the reactor 1. The partition frame 407 is divided into several regions, which are not interconnected. The inner wall of the partition frame 407 is movably connected to the outer wall of the diversion plate 406. A material passage hole is provided on the outer wall of the diversion plate 406. The interior of the diversion plate 406 is slidably connected to the inner wall of the partition frame 407 through the material passage hole. A connecting pipe 408 is fixedly connected to the outer wall of 07. A catalyst layer 5 is installed inside the connecting pipe 408. A rotating sealing disk 409 is rotatably connected inside the reactor 1. The bottom end of the rotating sealing disk 409 is in contact with the gas outlet end of the connecting pipe 408. A volume control component 6 for controlling the internal volume of the connecting pipe 408 is installed at the bottom inside the reactor 1. A power output device 7 for rotating the diversion disk 406, the rotating sealing disk 409, and driving the volume control component 6 is installed at the bottom inside the reactor 1.

[0028] The capacity control assembly 6 includes a fixed cylinder 601, which is fixedly installed on the side wall of the connecting pipe 408. A second piston 602 is slidably connected to the inner wall of the fixed cylinder 601. A connecting rod 603 is fixedly connected to one side of the second piston 602. A limiting disc 604 is fixedly connected to the output end of the power output device 7. The top end of the limiting disc 604 is movably connected to the bottom end of one end of the connecting rod 603. A movable groove is provided at the top end of the limiting disc 604. The top end of the limiting disc 604 is movably connected to the bottom end of one end of the connecting rod 603 through the movable groove.

[0029] The power output device 7 includes a second motor 701, which is fixedly installed at the bottom of the reactor 1. The output end of the second motor 701 is fixedly connected to a drive shaft 702. The top end of the drive shaft 702 passes through the bottom end of the diversion plate 406 and is fixed to the diversion plate 406. The top end of the drive shaft 702 passes through the bottom end of the diversion plate 406 and is fixed to the bottom end of the rotary sealing plate 409. The inner wall of the limiting disc 604 is fixed to the outer wall of the drive shaft 702.

[0030] A process for producing methyl acrylate uses the aforementioned reactor for methyl acrylate production. The process utilizes two reactors and includes: S01: Add acrylic acid liquid to the above reaction vessel 1, remove the air from the reaction vessel 1, and introduce methanol into the interior of the reaction vessel 1 through the feed pipe of the reaction vessel 1. Control the temperature inside the reaction vessel 1 to reach the boiling point of water to obtain mixed gas A. Mixed gas A includes methyl acrylate gas, methanol gas and water vapor. Mixed gas A flows out from the first gas outlet pipe of the reaction vessel. After the reaction is completed, the solution in the reaction vessel 1 includes acrylic acid and methyl 3-methoxypropionate. S02: Acrylic acid and methyl 3-methoxypropionate are separated by distillation; S03: Methyl 3-methoxypropionate is concentrated in another reactor 1, the air in reactor 1 is removed, and hydrogen is introduced into the reactor through the feed pipe of reactor 1. The temperature of reactor 1 is controlled to reach the boiling point of water to obtain mixed gas B. Mixed gas B includes hydrogen, methyl acrylate gas, methanol gas and water vapor. Mixed gas B is discharged from the first outlet pipe of reactor 1. S04: By using separation methods to separate the various substances in mixed gas A and mixed gas B, methyl acrylate is separated from other substances to obtain methyl acrylate, and methanol and hydrogen are recovered and reused.

[0031] The separation method involves introducing mixed gas A and mixed gas B into a separation tower, controlling the temperature inside the separation tower to decrease, and sequentially achieving phase separation between hydrogen, water, methyl acrylate and methanol.

[0032] The esterification reaction of methanol and acrylic acid to produce methyl acrylate is a reversible exothermic reaction. Therefore, in order to improve the conversion rate of methyl acrylate, which is the ratio of actual production to theoretical production, byproducts are generated during the esterification reaction. Among these byproducts, methyl 3-acryloyloxypropionate and methyl methoxypropionate account for a relatively high proportion. Methyl 3-acryloyloxypropionate can be decomposed into methyl acrylate and methyl p-hydroxypropionate upon heating. Methyl p-hydroxypropionate undergoes a dehydration reaction to produce methyl acrylate and water. Since the thermal decomposition temperature of methyl 3-acryloyloxypropionate is relatively high, no treatment is performed on the methyl 3-acryloyloxypropionate. It is then mixed with acrylic acid, which is then reused in the production of methyl acrylate. By increasing the content of methyl 3-acryloyloxypropionate in the acrylic acid, the generation of methyl 3-acryloyloxypropionate in subsequent methyl acrylate production can be reduced.

[0033] Since methyl 3-methoxypropionate is a byproduct, its content is relatively low. Therefore, in order to improve efficiency, methyl 3-methoxypropionate is centrally processed and concentrated in another reactor 1. Hydrogen gas is introduced into the methyl 3-methoxypropionate. This reactor 1 is the same as the reactor 1 used in the production of methyl acrylate.

[0034] Example 1: As Figure 1 - Figure 4 As shown, the output end of motor 301 rotates, causing disk 302 to rotate, which in turn causes transmission rod 303 to rotate. Transmission rod 303 causes moving frame 404 and transmission rod 303 to reciprocate. The reciprocating movement of moving frame 404 causes disk 403 and guide member 402 to swing back and forth. The reciprocating movement of transmission rod 303 causes piston 202 to move back and forth, thus causing the volume inside the pipe to increase and decrease for circulation. When methanol continuously enters the diversion pipe 401, and methanol begins to enter one of the pipes through guide member 402, although guide member 402 rotates, methanol will continue to flow into that pipe. At the same time, piston 202 on that pipe... The movement of stopper 202 increases the internal volume of the pipe, facilitating the flow of methanol. After a set time, guide 402 rotates in the reverse direction, still allowing methanol to enter the pipe. However, the reverse movement of piston 202 at this time reduces the internal volume of the pipe, increasing the internal pressure and making it difficult or impossible for methanol to enter. This continues until guide 402 rotates in the reverse direction to close the pipe, thus directing methanol to another pipe. During this time, the contact time between methanol and acrylic acid is ensured. Simultaneously, guide 402 at the outlet of one of the pipes opens its outlet, allowing mixed gas A to flow out. The same applies to the other pipe.

[0035] By setting up a flow splitter 4, a volume changer 2, and a power unit 3, the power unit 3 provides power to the flow splitter 4 and the volume changer 2. The guide 402 directs methanol to one of the parallel double pipes 405, while the guide 402 at the other end of the parallel double pipe 405 closes the gas outlet of that pipe to ensure regional sealing. At the same time, the power unit 3 moves the first piston 202 through transmission, thereby increasing the volume of the pipe, allowing methanol to enter the pipe and maintain a continuous sealing state. This is used to increase the contact time between methanol and acrylic acid and the catalyst layer 5, ensuring sufficient contact between methanol and acrylic acid, improving the single utilization rate of methanol, and reducing the subsequent methanol recovery cost.

[0036] Methanol and acrylic acid undergo an esterification reaction to produce methyl acrylate and water. This reaction is reversible; therefore, the methyl acrylate and water in reactor 1 should be removed promptly. A pump is fixedly connected to the feed pipe of reactor 1, and the pump's feed end is connected to a methanol storage tank. Methanol can be either liquid or gaseous when input. The methanol enters the diversion pipe 401. Due to the guidance of the guide element 402, the methanol enters one of the parallel double pipes 405. The gas outlet of this pipe is blocked by the guide element 402 in the other diversion pipe 401. During the entry process, due to the pump pressure and the rotation of the output end of motor 301, the disc 302 rotates, causing the transmission rod 303 to rotate. The transmission rod 303 contacts the inner wall of the contact hole, causing it to move, which in turn moves the piston 202 located on that pipe. This increases the internal volume of the pipe, allowing methanol to smoothly enter and complete the esterification reaction, producing methyl acrylate and water. However, because the internal temperature of reactor 1 reaches the boiling point of water, the methyl acrylate and water vaporize, and the methanol becomes gas. Since the duration of the sealed state of the pipe is controlled by the speed of the output end of motor 301, after the set time, the rotation of the transmission rod 303 contacts the inner wall of the movable hole, causing the moving frame 404 to move. This causes the outlet end of the pipe to be opened by the guide 402 in another branch pipe 401, while the internal volume of the pipe decreases, allowing mixed gas A to flow out. The digested acrylic acid in the pipe can enter the pipe through the outlet end, while the outlet end of the other pipe is blocked by the guide 402. The two pipes repeatedly and alternately undergo the reaction.

[0037] A variable volume component 2 is provided. Through the variable volume component 2, the inner wall volume of one of the parallel double pipes 405 increases and then decreases during the reaction. Therefore, methanol can enter the pipe smoothly in the early stage, but as the volume decreases, it becomes difficult for methanol to enter the pipe. This is because there is enough space inside the pipe at this time, and introducing more methanol would reduce the single utilization rate of methanol.

[0038] The internal temperature of the reactor 1 is set at the boiling point of water. Methanol, methyl acrylate, and water vaporize. As the power unit 3 continues to output power, the guide 402 at the other end opens the outlet of the pipeline. At this time, the volume of the pipeline gradually decreases, the mixed gas A is discharged, and the consumed acrylic acid will re-enter the pipeline from the outlet. The other pipeline enters methanol. The two pipelines can react alternately. With the input of methanol, the production rate of methyl acrylate can be guaranteed.

[0039] The process of producing methyl acrylate from methyl 3-methoxypropionate also uses the above-mentioned reactor 1. The reaction process is the same as that of producing methyl acrylate from methanol and acrylic acid. Methyl 3-methoxypropionate and hydrogen are mixed under acidic conditions to produce methyl acrylate, methanol and water.

[0040] In the process of producing methyl acrylate from methyl 3-methoxypropionate, although hydrogen is digested, methanol is produced. This methanol can be collected and then used in the esterification reaction of methanol and acrylic acid.

[0041] The production process of methyl acrylate involves collecting the byproducts from the reaction of methanol and acrylic acid to produce methyl acrylate, and concentrating methyl 3-methoxypropionate in it and transporting it to reactor 1. In reactor 1, methyl 3-methoxypropionate is reacted with hydrogen under acidic conditions, thereby converting methyl 3-methoxypropionate into methyl acrylate and methanol. Simultaneously, by controlling the temperature inside reactor 1, methyl acrylate and methanol are vaporized and discharged from reactor 1. In this way, methyl 3-methoxypropionate can be effectively utilized to produce methyl acrylate again, thereby improving the conversion rate of methyl acrylate.

[0042] The separation of the various substances within gas mixture A and gas mixture B is based on existing technology, and the specific separation process of gas mixture A and gas mixture B will not be described again.

[0043] Catalyst layer 5 primarily utilizes hydrogen ions for catalysis, employing acid as the catalyst. Ion exchange resins offer numerous advantages: they can be reused repeatedly, products are easily separated, and reactions are easily controlled. Therefore, this process uses a strongly acidic cation exchange resin for catalyst layer 5 because its active hydrogen ions readily dissociate in water. Its framework is entirely polystyrene, and the main product is a "sulfonic acid type" strongly acidic cation exchange resin. Theoretically, the catalyst's mass and properties remain unchanged before and after the chemical reaction, allowing for unlimited use. However, in practice, the cation exchange resin primarily ionizes to release hydrogen ions. Furthermore, cation exchange resins are also used in the production of methyl acrylate from methyl 3-methoxypropionate.

[0044] The use of reactor 1, flow divider 4, volume changer 2, and power unit 3 enables the completion of two different reactions in the production process of methyl acrylate: one is the esterification reaction of methanol and acrylic acid to produce methyl acrylate, and the other is the mixed reaction of methyl 3-methoxypropionate and hydrogen to produce methyl acrylate. Reactor 1 and its internal devices can complete the above two reactions, ensuring the effectiveness of reactor 1, flow divider 4, volume changer 2, and power unit 3, thereby improving the practicality of the relevant equipment.

[0045] Example 2: To further increase the production speed of methyl acrylate, such as... Figure 5 - Figure 11 As shown, a partition 8 is fixedly connected to the reactor 1. The outlet of the connecting pipe 408 passes through the bottom of the partition 8. Acrylic acid liquid is at the top of the partition 8. Methanol enters the interior of the distribution plate 406 through the bottom of the reactor 1. The output of the second motor 701 rotates, thereby causing the drive shaft 702 to rotate and the distribution plate 406 to rotate. At the same time, the limiting plate 604 rotates. The connecting rod 603 is restricted by the movable groove on the limiting plate 604. Meanwhile, the connecting rod 603 and the second piston 602 are fixed together. The second piston 602 and the fixed cylinder 601 are... The connection is sliding, thus restricting the rotation of the disc 604. Force is applied to the connecting rod 603 via the movable groove. Due to the design of the movable groove, the second piston 602 moves back and forth inside the fixed cylinder 601, thereby controlling the change in the internal volume of the connecting pipe 408. Simultaneously, the rotation of the drive shaft 702 causes the rotary sealing disc 409 to rotate. The design of the rotary sealing disc 409 ensures that during its rotation, the air outlet of the connecting pipe 408 undergoes a cycle of opening and closing. For a single connecting pipe 408, specifically... The process is as follows: When the feed hole on the diverter plate 406 is aligned with the area in the separator 407 corresponding to the connecting pipe 408, methanol is pumped into the connecting pipe 408 through the separator 407. Simultaneously, the second piston 602 inside the fixed cylinder 601 on the connecting pipe 408 moves, increasing the internal volume of the connecting pipe 408, allowing methanol to smoothly enter the interior of the connecting pipe 408. At the same time, the rotating sealing plate 409 seals the vent of the connecting pipe 408. The sealing time of the vent of the connecting pipe 408 is determined by the second motor 701. The rotation speed at the output end is controlled. During the sealing period, methanol, acrylic acid, and catalyst layer 5 come into contact with each other and react. As the drive shaft 702 rotates, after sealing, the rotating sealing disc 409 rotates, causing the outlet end of the connecting pipe 408 to open. At the same time, the second piston 602 inside the fixed cylinder 601 moves in the opposite direction, thereby reducing the internal volume of the connecting pipe 408, which can effectively discharge the substances inside the connecting pipe 408. Meanwhile, the acrylic acid liquid on the partition 8 enters the connecting pipe 408 through the outlet end of the connecting pipe 408.

[0046] Although methanol gradually vaporizes inside reactor 1, its density is lower than that of acrylic acid, whether vaporized or liquid. Therefore, methanol rises while acrylic acid tends to fall, allowing methanol, acrylic acid, and catalyst layer 5 to fully contact and react. The volume control component 6 and the volume change component 2 have the same function: to change the volume inside the pipe or connecting pipe 408 to allow methanol to enter.

[0047] Experimental Group: An esterification reactor (100L capacity) was used. This reactor contained no other devices and was equipped with a catalyst. The esterification reactor was designed for the production of methyl acrylate. 10 mol of acrylic acid and 10 mol of methanol were used. The 10 mol of acrylic acid was introduced into the esterification reactor at a fixed rate of 1 mol per minute, and 10 mol of methanol was continuously introduced. Other gases in the reactor were continuously collected until no gas was generated. The internal temperature of the reactor was controlled at the boiling point of water. The collected mixed gas was passed through a separation tower and a cooling tower to obtain methyl acrylate and methanol. The contents of methyl acrylate and methanol were recorded. The amount of methanol required to introduce 10 mol until no gas was generated in the reactor was recorded. The above process was repeated three times, and the data were recorded and averaged.

[0048] Example 1: Using the reaction vessel and other devices described in Example 1, the experimental procedure was the same as required in Experiment 1, and was repeated three times. Data were recorded and the average value was taken. Example 2: Using the reactor and other devices in Example 2, the experimental procedure was the same as that in Experiment 1, and was repeated three times. Data were recorded and the average value was taken.

[0049] The data is compiled into Table 1: Table 1 (Unit: mol)

[0050] As can be seen from Table 1, the configuration of the diversion component 4, the variable capacity component 2, and the power device 3 in Example 1, and the diversion component 4, the capacity control component 6, and the power output device 7 in Example 2, by controlling the contact time between methanol and acrylic acid, allows methanol to fully contact with acrylic acid, thereby generating methyl acrylate. This improves the single utilization rate of methyl acrylate and reduces the subsequent methanol recovery cost.

[0051] The methanol mentioned above can be reused after collection.

[0052] The mixed solutions from the reactors in the above experimental group, Example 1 and Example 2 were collected and then divided into three equal parts.

[0053] Experimental Group: Acrylic acid and methyl 3-methoxypropionate in the mixed solution were separated by distillation. The methyl 3-methoxypropionate was concentrated in another reaction vessel, and the air in the reaction vessel was removed. Excess hydrogen gas was introduced into the reaction vessel through the feed pipe, and the temperature of the reaction vessel was controlled to reach the boiling point of water, resulting in mixed gas B. Mixed gas B included hydrogen, methyl acrylate gas, methanol gas, and water vapor. Mixed gas B was discharged from the first outlet pipe of the reaction vessel. Methyl acrylate was separated from mixed gas B, and the methyl acrylate content was recorded. The operation was repeated three times, and the average value was taken.

[0054] Example 1: The operation process is the same as that of the experimental group, repeated three times, and the average value is taken; Example 2: The operation process is the same as that of the experimental group, and the operation is repeated three times, and the average value is taken.

[0055] The data is compiled into Table 2: Table 2 (Unit: mol)

[0056] Table 3 shows the total content of methyl acrylate produced in the experimental group, Example 1, and Example 2.

[0057] Table 3 (Unit: mol)

[0058] Tables 1, 2, and 3 show that by concentrating and transporting methyl 3-methoxypropionate to a reactor, where it reacts with hydrogen under acidic conditions, the methyl 3-methoxypropionate is utilized to produce methyl acrylate, thereby increasing the conversion rate of methyl acrylate.

[0059] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended embodiments and their equivalents.

Claims

1. A reactor for the production of methyl acrylate, comprising a reaction vessel (1), wherein a gas outlet pipe is fixedly connected to the top of the reaction vessel (1), and a feed pipe is fixedly connected to the bottom of the reaction vessel (1), characterized in that: A flow divider assembly (4) is installed at the bottom of the reactor (1). The diversion assembly (4) includes a parallel double pipe (405), which is fixedly installed at the bottom inside the reactor (1). The parallel double pipe (405) is inclined as a whole. The outlet and inlet ends of the parallel double pipe (405) are respectively fixedly connected to diversion pipes (401). In terms of vertical height, the inlet end of the parallel double pipe (405) is lower than the outlet end of the parallel double pipe (405). The interior of the two diversion pipes (401) is rotatably connected to guide members (402). The top ends of the two diversion pipes (401) are rotatably connected to turntables (403). The bottom end of the turntables (403) penetrates the diversion pipes (401). The outer wall of 01) and the top of the guide (402) are fixed together. The top of the diverter (401) is slidably connected to the moving frame (404). The bottom of the moving frame (404) and the top of the turntable (403) are movably connected. The parallel double pipe (405) is equipped with a variable volume component (2) for controlling the internal volume of the parallel double pipe (405). The reactor (1) is equipped with a power device (3) for driving the moving frame (404) to move. The diverter (401) and the feed pipe at the bottom of the parallel double pipe (405) are fixed together. The internal of the parallel double pipe (405) is fixedly connected to a catalyst layer (5). A cylinder is fixedly connected to one side of the turntable (403), and an arc hole is provided on one side of the movable frame (404). One side of the turntable (403) is slidably connected to one side of the movable frame (404) through the cylinder and the arc hole. The parallel double pipe (405) includes two parallel pipes that are fixed to each other. The two pipes are not connected internally. The variable capacity component (2) includes a cylinder (201). The outer walls of the two pipes are respectively fixedly connected to the cylinder (201). A piston (202) is fixedly and slidably connected inside the cylinder (201). A connecting frame (203) is fixedly connected to one end of the piston (202). The other end of the connecting frame (203) is fixed to one side of the other piston (202). The connecting frame (203) is connected to the output end of the power device (3). The power unit (3) includes a first motor (301), which is fixedly installed inside the reactor (1). The output end of the first motor (301) is fixedly connected to a disc (302), and the bottom end of the disc (302) is fixedly connected to a transmission rod (303). The transmission rod (303) is movably connected to the connecting frame (203) and the moving frame (404) respectively. The top of the connecting frame (203) is provided with a contact hole, and the connecting frame (203) is movably connected to the outer wall of the transmission rod (303) through the inner wall of the contact hole. The top of the movable frame (404) is provided with a movable hole, and the movable frame (404) is movably connected to the outer wall of the transmission rod (303) through the inner wall of the movable hole.

2. A reactor for the production of methyl acrylate, comprising a reaction vessel (1), wherein a gas outlet pipe is fixedly connected to the top of the reaction vessel (1), and a feed pipe is fixedly connected to the bottom of the reaction vessel (1), characterized in that: A flow divider assembly (4) is installed at the bottom of the reactor (1). The diversion assembly (4) includes a diversion plate (406), the bottom end of which is rotatably connected to the bottom end inside the reactor (1). A partition frame (407) is fixedly connected to the bottom end inside the reactor (1). The partition frame (407) is divided into several regions, which are not interconnected. The inner wall of the partition frame (407) is movably connected to the outer wall of the diversion plate (406). A material passage hole is provided on the outer wall of the diversion plate (406). The interior of the diversion plate (406) is slidably connected to the inner wall of the partition frame (407) through the material passage hole. A connecting pipe (408) is fixedly connected to the outer wall of the reactor (1). A catalyst layer (5) is installed inside the connecting pipe (408). A rotating sealing disk (409) is rotatably connected inside the reactor (1). The bottom end of the rotating sealing disk (409) is in contact with the gas outlet end of the connecting pipe (408). A volume control component (6) for controlling the internal volume of the connecting pipe (408) is installed at the bottom inside the reactor (1). A power output device (7) for rotating the flow divider (406), the rotating sealing disk (409), and driving the volume control component (6) is installed at the bottom inside the reactor (1). The capacity control assembly (6) includes a fixed cylinder (601), which is fixedly installed on the side wall of the connecting pipe (408). A second piston (602) is slidably connected to the inner wall of the fixed cylinder (601). A connecting rod (603) is fixedly connected to one side of the second piston (602). A limiting disc (604) is fixedly connected to the output end of the power output device (7). The top end of the limiting disc (604) is movably connected to the bottom end of one end of the connecting rod (603). The top end of the limiting disc (604) is provided with a movable groove. The top end of the limiting disc (604) is movably connected to the bottom end of one end of the connecting rod (603) through the movable groove. The power output device (7) includes a second motor (701), which is fixedly installed at the bottom of the reactor (1). The output end of the second motor (701) is fixedly connected to a drive shaft (702). The top end of the drive shaft (702) passes through the bottom end of the diversion plate (406) and is fixed to the diversion plate (406). The top end of the drive shaft (702) passes through the bottom end of the diversion plate (406) and is fixed to the bottom end of the rotary sealing plate (409). The inner wall of the limiting disc (604) is fixed to the outer wall of the drive shaft (702).

3. A process for producing methyl acrylate, characterized in that: The process employs a reactor for the production of methyl acrylate as described in any one of claims 1 or 2, wherein the process uses two reactors and includes: S01: Add acrylic liquid to the reactor (1), remove the air from the reactor (1), and introduce methanol into the reactor (1) through the feed pipe of the reactor (1) to control the internal temperature of the reactor (1) to reach the boiling point of water, so as to obtain mixed gas A. Mixed gas A includes methyl acrylate gas, methanol gas and water vapor. Mixed gas A flows out from the No. 1 outlet pipe of the reactor. After the reaction is completed, the solution in the reactor (1) includes acrylic acid and methyl 3-methoxypropionate. S02: Acrylic acid and methyl 3-methoxypropionate are separated by distillation; S03: Methyl 3-methoxypropionate is concentrated in another reactor (1), the air in the reactor (1) is removed, hydrogen is introduced into the reactor through the feed pipe of the reactor (1), and the temperature of the reactor (1) is controlled to reach the boiling point of water to obtain mixed gas B, which includes hydrogen, methyl acrylate gas, methanol gas and water vapor. Mixed gas B is discharged from the No. 1 outlet pipe of the reactor (1). S04: By using a separation method, the various substances in mixed gas A and mixed gas B are separated into phases, methyl acrylate is separated from other substances to obtain methyl acrylate, and methanol and hydrogen are recovered and reused.

4. The methyl acrylate production process according to claim 3, characterized in that: The separation method includes introducing mixed gas A and mixed gas B into a separation tower, controlling the temperature inside the separation tower to decrease, and sequentially achieving phase separation between hydrogen, water, methyl acrylate and methanol.

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